nicholas jolley - causality and mind [2014][a]

CAUSALITY AND MIND

OUP CORRECTED PROOF – FINAL, 4/11/2013, SPi

Causality and MindEssays on Early Modern Philosophy

NICHOLAS JOLLEY

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Acknowledgements

I am grateful to the publishers and editors for permission to reprintmaterial thatpreviously appeared in other places. Chapter 1, ‘Scientia and Self-Knowledge inDescartes’, first appeared in Tom Sorell, G.A.J. Rogers and Jill Kraye (eds.),Scientia in Early Modern Philosophy (Dordrecht: Springer, 2010), pp. 83–97;Chapter 2, ‘Descartes and theAction of Body onMind’, in Studia Leibnitiana 19(1987), 41–53; Chapter 3, ‘Intellect and Illumination in Malebranche’, in Jour-nal of the History of Philosophy 32 (1994), 209–24; Chapter 4, ‘Sensation,Intentionality, and Animal Consciousness: Malebranche’s Theory of theMind’, in Ratio (New Series) 8 (1995), 128–42; Chapter 5, ‘Malebranche onthe Soul’, in Steven Nadler (ed.), The Cambridge Companion to Malebranche(Cambridge and New York: Cambridge University Press, 2000), pp. 31–58;Chapter 6, ‘Occasionalism and Efficacious Laws in Malebranche’, in PeterA. French and Howard K. Wettstein (eds.), Renaissance and Early ModernPhilosophy, Midwest Studies in Philosophy 26 (2002), 245–47; Chapter 7,‘Leibniz and Malebranche on Innate Ideas’, in Philosophical Review 97 (1988),71–91; Chapter 8, ‘Leibniz and the Excellence of Minds’, in M. Carrara,A.M. Nunziante, and G. Tomasi (eds.), Individuals, Minds, and Bodies: Themesfrom Leibniz, Studia Leibitiana Sonderheft 32 (2004), 125–40; Chapter 9, ‘Leib-niz and Occasionalism’, in Donald Rutherford and J.A. Cover (eds.), Leibniz:Nature and Freedom (New York: Oxford University Press, 2005), pp. 121–34;Chapter 10, ‘Causality and Creation in Leibniz’, in Barry Smith (ed.), Re-Thinking Leibniz, The Monist 61 (1998), 591–611; Chapter 11, ‘Leibniz andthe Causal Self-Sufficiency of Substances’, appears here in English for the firsttime; it was originally published in a French translation as ‘Leibniz et l’autosuffi-sance causale des substances’, in Causalité et liberté dans la philosophie du XVIIesiècle, Revue philosophique de Louvain 107 (2009), 699–716; Chapter 12, ‘Leibnizand Phenomenalism’, in Studia Leibnitiana 18 (1986), 39–51; Chapter 13, ‘Lock-ean Abstractionism versus Cartesian Nativism’, in P. Hoffman, D. Owen, andG. Yaffe (eds.),Contemporary Perspectives on EarlyModern Philosophy: Essays inHonor of Vere Chappell (Toronto: Broadview Press, 2008), pp. 157–71;Chapter 14, ‘Dull Souls and Beasts: Two Anti-Cartesian Polemics in Locke’, inPetr Glombicek and James Hill (eds.), Essays on the Concept of Mind in EarlyModern Philosophy (Newcastle-upon-Tyne: Cambridge Scholars Publishing,2010), pp. 97–113; Chapter 15, ‘Berkeley, Malebranche, and Vision in God’, inJournal of the History of Philosophy 34 (1996), 535–48; Chapter 16, ‘Berkeley andMalebranche on Causality and Volition,’ in J. Cover and M. Kulstad (eds.),Central Themes in Early Modern Philosophy: Essays Presented to Jonathan


Bennett (Indianapolis: Hackett, 1990), pp. 227–44; and Chapter 17, ‘Hume,Malebranche, and the Last Occult Quality’, in Justin Broackes, ChristopherS. Hill, and Alison Simmons (eds.),Modern Philosophy, Philosophical Topics 31(2003), 199–213, usedwith the permission ofThePermissionsCompany, Inc., onbehalf of the University of Arkansas Press, www.uapress.com.

For the purposes of this collection I have standardized and, where neces-sary, updated the system of references. I have also taken the opportunity tocorrect a number of mistakes and stylistic infelicities. In the Introduction andthe notes I have drawn attention to those issues on which, as I now think, myoriginal views stand in need of correction in the light of recent scholarship.

I am grateful to Peter Momtchiloff and the delegates of Oxford UniversityPress for encouraging me to produce this collection. My many debts tocolleagues in the profession are acknowledged in the essays themselves.


vi Acknowledgements

http://www.uapress.com

Contents

Abbreviations viii

Introduction 1

1. Scientia and Self-Knowledge in Descartes 12

2. Descartes and the Action of Body on Mind 28

3. Intellect and Illumination in Malebranche 43

4. Sensation, Intentionality, and Animal Consciousness: Malebranche’sTheory of the Mind 57

5. Malebranche on the Soul 69

6. Occasionalism and Efficacious Laws in Malebranche 92

7. Leibniz and Malebranche on Innate Ideas 105

8. Leibniz and the Excellence of Minds 121

9. Leibniz and Occasionalism 135

10. Causality and Creation in Leibniz 151

11. Leibniz and the Causal Self-Sufficiency of Substances 169

12. Leibniz and Phenomenalism 183

13. Lockean Abstractionism Versus Cartesian Nativism 199

14. Dull Souls and Beasts: Two Anti-Cartesian Polemics in Locke 214

15. Berkeley, Malebranche, and Vision in God 229

16. Berkeley and Malebranche on Causality and Volition 242

17. Hume, Malebranche, and the Last Occult Quality 254

Bibliography 268Index 275


Abbreviations

A German Academy of Sciences (ed.), G.W. Leibniz: Sämtliche Schriften undBriefe (Darmstadt and Berlin: Berlin Academy, 1923–)

AG R. Ariew and D. Garber (trans.), G.W. Leibniz: Philosophical Essays(Indianapolis and Cambridge, MA: Hackett, 1989)

AT C. Adam and P. Tannery (eds.), Oeuvres de Descartes, 12 vols. (Paris:Vrin, 1897–1913; repr. Paris: Vrin, 1964–76)

CB J. Cottingham (ed. and trans.), Descartes’ Conversation with Burman(Oxford: Clarendon Press, 1976)

CL E.S. De Beer (ed.), The Correspondence of John Locke, 8 vols. (Oxford:Clarendon Press, 1976–89)

CSM J. Cottingham, R. Stoothoff and D. Murdoch (trans.), The PhilosophicalWritings of Descartes, 2 vols. (Cambridge: CambridgeUniversity Press, 1985)

CSMK J. Cottingham, R. Stoothoff, D. Murdoch, and A. Kenny (trans.), ThePhilosophical Writings of Descartes: The Correspondence (Cambridge:Cambridge University Press, 1991)

DHP Berkeley, Three Dialogues between Hylas and Philonous

DM Leibniz, Discourse on Metaphysics

DMR Malebranche, Dialogues on Metaphysics and on Religion

Du L. Dutens (ed.), G.G. Leibnitii Opera Omnia (Geneva, 1768)

E David Hume, An Enquiry Concerning Human Understanding inL.A. Selby-Bigge and P.H. Nidditch (eds.), Enquiries Concerning HumanUnderstanding and Concerning the Principles of Morals (Oxford:Clarendon Press, 1975)

ED R.I. Aaron and J. Gibb (eds.), An Early Draft of Locke’s Essay together withExcerpts from his Journals (Oxford: Clarendon Press, 1936)

Essay P.H. Nidditch (ed.), John Locke: An Essay Concerning HumanUnderstanding (Oxford: Clarendon Press, 1975)

G C.I. Gerhardt (ed.), Die Philosophischen Schriften von G.W. Leibniz, 7vols. (Berlin: Weidmann, 1875–90)

Gr G. Grua (ed.), G. W. Leibniz: Textes inédits d’après les manuscrits de labibliothèque provinciale d’Hanovre, 2 vols. (Paris: Presses Universitairesde France, 1948)

H E.M. Huggard (trans.), G.W. Leibniz: Theodicy (LaSalle, Illinois: OpenCourt, 1985)

JS N. Jolley (ed.), and D. Scott (trans.), Nicolas Malebranche: Dialogues onMetaphysics and on Religion (Cambridge: Cambridge University Press, 1997)


L L.E. Loemker (trans. and ed.), G.W. Leibniz: Philosophical Papers andLetters, 2nd edn. (Dordrecht: Reidel, 1969)

LA H.T. Mason (ed. and trans.), The Leibniz-Arnauld Correspondence(Manchester: Manchester University Press, 1967)

LJ A.A. Luce and T.E. Jessop (eds.), The Works of George Berkeley, Bishop ofCloyne, 9 vols. (London: Nelson, 1948–57)

LO T. Lennon and P.J. Olscamp (trans.), Nicolas Malebranche: The SearchAfter Truth, rev. edn (Cambridge: Cambridge University Press, 1997)

LW The Works of John Locke, 10 vols. (London, 1823; repr. Aalen, 1963)

MLR A. Robinet (ed.), Malebranche et Leibniz: relations personnelles (Paris:Vrin, 1955)

NE Leibniz, New Essays on Human Understanding

OCM A. Robinet (dir.), Oeuvres complètes de Malebranche, 20 vols. (Paris: Vrin,1958–67)

P G.H.R. Parkinson (trans.), G.W. Leibniz: Philosophical Writings (London:Dent, 1973)

PC Berkeley, Philosophical Commentaries

PHK Berkeley, Principles of Human Knowledge

R P. Riley (trans.), Leibniz: Political Writings, 2nd edn (Cambridge:Cambridge University Press, 1988)

RB P. Remnant and J. Bennett (trans.), G.W. Leibniz: New Essays on HumanUnderstanding, 2nd edn (Cambridge: Cambridge University Press, 1996)

SAT Malebranche, The Search After Truth

T L.A. Selby-Bigge and P.H. Nidditch (eds.), David Hume: A Treatise ofHuman Nature, 2nd edn (Oxford: Clarendon Press, 1978)

WF R. Woolhouse and R. Francks (trans. and eds.), G.W. Leibniz:Philosophical Texts (Oxford: Oxford University Press, 1998)


Abbreviations ix

Introduction

When I first became interested in the history philosophy over forty years ago,I was reliably informed that professional philosophers tended to study theirgreat, dead predecessors as if they were colleagues at Oxford or Princeton. Suchan approach seemed strange to me. The seventeenth century, the period whichmost fascinated me, was not only the age of the scientific revolution; it was alsoan age of political and religious turmoil in which people were prepared to fightand die for their beliefs. It appeared to me prima facie unlikely that the spirit ofthe age could fail to shape the problems that philosophers addressed and eventhe constraints on what would count as a satisfactory solution. My scepticismabout the prevailing approach to the discipline increased when I turned to thecommentators themselves; I discovered that in their eyes the great, deadphilosophers were not so great after all. They were prone to making elementaryblunders which even amoderately intelligent freshman could expose. It seemedto me that the history of philosophy was in need of radical reorientation.Fortunately, a number of my contemporaries were having similar doubtsabout the wisdom of the ‘collegialist’ approach as it has come to be called.1

As a result, the last forty years have been an exciting time in which to practisethe history of early modern philosophy; they have witnessed something like arevolution in the discipline.One aspect of the revolution is that scholars have looked beyond the famous

peaks and begun to study seriously philosophers who were formerly consignedto the footnotes. In the eighteenth century it is Thomas Reid who is perhapsthe most conspicuous example of a philosopher who has begun to attractserious scholarly attention; in the seventeenth century it is clearly Male-branche. Malebranche’s system used to be regarded as extravagant, bizarre,and mystical; thus commenting on Locke’s remark that the doctrine of visionin God is ‘an opinion that spreads not and is like to die of itself ’ (LW IX 210)

1 Some of the leading proponents of a more historical or contextualist approach to the historyof philosophy have been historians of political thought such as John Dunn, Quentin Skinner, andRichard Tuck; as a graduate student and Research Fellow at Cambridge in the 1970s I was muchinfluenced by their work.


John Mackie could write: ‘How right he was!’ and expect a sympathetic nod ofagreement from his readers.2 Few scholars of early modern philosophy wouldtreat the doctrine of vision in God in such a cavalier spirit today; it is nowwidely recognized as a philosophically imaginative and well-motivated versionof the representative theory of perception. It is not only the vision in God, ofcourse, but Malebranche’s doctrine of occasionalism and his theodicy thathave become the focus of scrupulous and detailed philosophical analysis.Malebranche is now seen as the author of a fascinating philosophical systemworthy to stand in comparison with the systems of Descartes, Spinoza, andLeibniz.

But the case for studying a system such as Malebranche’s rests not only onthe intrinsic interest of his philosophical teachings; it rests also on the fact thata knowledge of his system makes it possible to tell a more compelling andconvincing narrative about the development of early modern philosophy.Such knowledge allows us to see the familiar mountain peaks from newperspectives. Consider the case, for instance, of Leibniz’s Discourse on Meta-physics, the work from which he himself dated his philosophical maturity. Ifthe Discourse is read immediately after Descartes’ Meditations or even Spin-oza’s Ethics, it can seem a deeply puzzling work. It is true, of course, that Leibnizmakes a few incidental criticisms of Descartes’ teachings, but he conveys littlesense that he is engaged in a continuous philosophical conversation with thefather of modern philosophy. It was perhaps in part the feeling that the workmade so little sense when viewed in these terms that led commentators such asBertrand Russell and Louis Couturat to approach it from a wholly differentangle. Over a hundred years ago Russell argued that the key to understandingthe doctrines of this work was Leibniz’s distinctive concept-containmenttheory of truth; indeed, the work used to be cited as the prime exhibit in supportof the ‘logicist’ interpretation of Leibniz’s philosophy according to whichhe derived his metaphysical doctrines from his theory of truth.3 It was thisapproach that dominated Leibniz studies, at least in the English-speaking world,for the best part of a century.

The logicist reading of the Discourse on Metaphysics has many attractions,but it suffers from one serious defect: it is forced to treat much of the work asirrelevant to Leibniz’s main purpose. (One editor, who was clearly influencedby this reading, even went so far as to omit the first seven sections of the work

2 J.L. Mackie, Problems from Locke (Oxford: Clarendon Press, 1976), p. 39. Mackie’s book is afine example of analytic or collegialist history of philosophy that succeeds in conveying Locke’scombination of subtlety and respect for common sense, but it does not challenge prevailingwisdom about the discipline.

3 Bertrand Russell, A Critical Exposition of the Philosophy of Leibniz (London: Allen andUnwin, 1900). A second edition was published in 1937. For Couturat’s interpretation, see ‘OnLeibniz’s Metaphysics’, H.G. Frankfurt (ed.), Leibniz: A Collection of Critical Essays (New York:Doubleday, 1972), pp. 19–45.


2 Introduction

as being of no philosophical interest to modern readers.)4 By contrast, once weread the work against the background of Malebranche’s philosophy, we canbegin to see the Discourse on Metaphysics as a coherent and unified whole; theDiscourse emerges as a work that systematically opposes Malebranche’s signa-ture doctrines of occasionalism and vision in God and his own distinctivetheodicy. To say this is not to say that it is simply false to see the Discourse as awork in which Leibniz tries to derive the metaphysical doctrines of the pre-established harmony from his theory of truth; indeed, it may be that Leibniz’sopposition to Malebranche is systematic, in part at least, precisely in virtue ofthe fact that he deploys the theory of truth in the service of argumentsdesigned to expose the falsity of Malebranchian teachings. But I believe thatin interpreting a great philosophical work we should at least seek for a unifyingprinciple, and in the case of the Discourse that principle is furnished by therefutation of Malebranche. In place of the Malebranchian system Leibnizargues for a universe of cognitively and causally active substances, includingspirits, which reflect divine perfections such as omniscience and omnipotence.It is indeed by virtue of their participation in such perfections that God decidesto bestow on spiritual substances the maximal happiness that the overall orderof things allows.

CAUSALITY

It is traditional to regard Hume as the starting-point for all modern discus-sions of causality, and I have no wish to challenge this particular orthodoxy.But one aim of the essays in this volume is to portray Hume as the culminationrather than the beginning of a story; that is, I seek to tell a narrative that beginswith Descartes and ends with Hume. A continuing debate over the nature ofcausality is the focus of a number of papers in the volume.For all his role as the so-called father of modern philosophy Descartes did

no serious re-thinking about the nature of causality.5 Rather, in the eyes ofboth his contemporaries and modern scholars, Descartes was content to takeover traditional Scholastic assumptions about causality without questioningwhether these assumptions had any real place within the new mechanisticworld-picture; indeed, it is often through Descartes’ own formulations thatthese assumptions have become familiar to modern readers. As those whohave struggled to understand the cosmological argument of the Third

4 See P 18. In section 8 of the Discourse on Metaphysics (G IV 432–3: P 18) Leibniz begins toderive metaphysical consequences from his concept-containment theory of truth.

5 Cf. Tad Schmaltz, Descartes on Causation (New York: Oxford University Press, 2008),Introduction.


Introduction 3

Meditation are aware, Descartes endorses a causal principle that is at least aclose cousin of the ‘heirloom’ or contagion model of causality according towhich ‘tropes’ or property-instances are passed on from cause to effect. To saythis, however, is not to say that Descartes’ commitment to apparently prob-lematic causal claims is internally incoherent. Thus Descartes’ assertion thatthere is genuine causal interaction between mind and body can be reconciledwith his commitment to the Causal Adequacy Principle which states that theremust be at least as much reality in the total efficient cause as the effect. Such areconciliation is indeed quite straightforward if Descartes is allowed to invokeGod’s creative activity as a causal background condition. Descartes’ assertionof mind–body interaction is even less of a problem if one adopts a Humeanview of causality according to which anything can cause anything providedcertain formal conditions are satisfied; the Humean theory poses no con-straints on the nature of the things or substances that can stand in causalrelations. Whatever the sources of the so-called scandal of Cartesian inter-action, they are not to be found in either Descartes’ or Hume’s teachingsconcerning causality.

Descartes’ teachings about causality may not lead to internal incoherence,but they are not innovative. Among Descartes’ successors, the philosopherwho did most to rethink the nature of causality is his unorthodox disciple,Malebranche. It would of course be misleading to describe Malebranche’soccasionalism as an entirely new doctrine; it was anticipated in Islamicphilosophy of the Middle Ages by Al-Ghazali. Malebranche’s distinctivecontribution lies in his defence of the doctrine by the means of powerfularguments. One such argument turns on the doctrine of continuous creationthat Malebranche shares with Descartes and his medieval predecessors;according to this doctrine, God conserves the universe by continuously creat-ing it. On Malebranche’s view, a rigorous interpretation of this doctrine showsthat there is no room for secondary causality, that is, causality on the part ofcreatures. A second argument is even more important for the subsequentdevelopment of thought about causality: it turns on a strictly rationalisticanalysis of the causal relation: ‘a true cause, as I understand it, is one suchthat the mind perceives a necessary connection between it and its effect’ (SAT6.2.3, OCM II 316; LO 450). It was this argument that Hume was to adapt forhis own distinctive purposes.

Occasionalism is a philosophical theory that raises a host of intriguingissues of interpretation. On the face of it, the theory seems straightforwardenough: God is the one true cause, and events in the created world are merelythe occasions on which God’s genuine causal power is exercised. But problemsarise as soon as we consider Malebranche’s thesis that God brings aboutparticular events through laws of nature that are his general volitions; inparticular, it is difficult to know what to make of Malebranche’s repeatedclaim that the laws of nature are themselves efficacious. Some readers, such as


4 Introduction

Steven Nadler, have argued that Malebranche’s God does not confine himselfto willing the laws of nature and the initial conditions of the universe; inaddition, he must ensure through a series of particular or individual volitionsthat creatures behave in accordance with the laws or his general volitions.6

I argue that Malebranche should be taken at his word when he repeatedly saysthat the laws of nature are themselves efficacious. I try to spell out aninterpretation of how Malebranche could coherently say that the laws ofnature, in conjunction with the initial conditions, bring about particularevents such as the motion of the billiard ball on a table following collisionwith another ball. On the interpretation I propose, it is a mistake to supposethat there is any need for a further series of individual volitions on God’s partto ensure the conformity of bodies to laws. Such action on God’s part would inany case be in breach of the principle that God acts in the simplest ways.Making sense of occasionalism is an intriguing and challenging philosoph-

ical exercise in its own right. But to understand occasionalism it is not enoughto understand its internal logic or coherence; we need to understand itsphilosophical motivation. In my view one of Malebranche’s chief goals inadvancing the doctrine is to extend the Cartesian anti-Scholastic revolution tocausality; in the helpful words of one French scholar, causality is ‘the lastoccult quality’ and thus needs to be banished from the created world ofmechanistic physics.7 For Malebranche, the successor concept to the obscureand confused idea of causality is the clear and distinct concept of law: sciencein his eyes is essentially concerned to explain natural phenomena in terms ofinitial conditions and covering laws that can be expressed in mathematicalterms. Reading occasionalism in this way has distinct advantages: it helps tosolve the problem of determining exactly what is at issue in the debate betweenLeibniz and Malebranche. In one form or another this is an issue that haspuzzled scholars ever since Leibniz’s earliest readers. Thus both Arnauld andBayle criticized Leibniz for seeming to travesty Malebranche’s occasionalismby complaining that it introduces perpetual miracles into the world. In myview Leibniz’s real concern is to reinstate the traditional Aristotelian thesisthat scientific explanations appeal to causality: for Leibniz, laws of course havea role to play in science, but they need to be grounded in the genuine causalpowers or forces of created substances.The idea that causality, forMalebranche, is the last occult quality is central to

understanding his relationship to Hume. As we have said, Hume may be in asense the point of departure for all modern discussions of causality, but in oneway he is perhaps less of an innovator than Malebranche; unlike Malebranche,

6 Steven Nadler, ‘Occasionalism and General Will in Malebranche’, Journal of the History ofPhilosophy 31 (1993), 31–47.

7 L. Lévy-Bruhl, History of Modern Philosophy in France, quoted in C.J. McCracken, Male-branche and British Philosophy (Oxford: Clarendon Press, 1983), p. 102.


Introduction 5

he fails to perceive that on the new mechanistic physics it is at least debatablewhether there is a genuine role for the concept of causality to play. Of course, itwould be wrong to suppose that Hume is committed to the existence of robustcausal powers in nature. Unless we adopt the revisionist stance of somemodernscholars, we may agree that Hume’s treatment of causality is thoroughlyreductionistic in spirit:8 causality is to be reduced to constant conjunctionsand the subjective tendency of the mind to project necessary connections on tothe world. But on any straightforward reading he does share with Leibniz thetraditional assumption that science is engaged in the search for causes.

A further dimension of the early modern debate over causality is a theo-logical one. In The Search After Truth Malebranche insists that one of theprincipal dangers of ascribing genuine causal powers to finite substances isthat it leads to idolatry; as he rather comically puts it, it encourages people topay homage to leeks and onions (SAT 6.2.3, OCM II 311; LO 447). Leibniz’srival insistence on a world of created substances endowed with robust causalpowers must also be seen as an expression of a distinctive theological theme:this is the idea that the created universe mirrors the perfections of its creator.Indeed, there is even a sense in which Leibniz’s created substances mirrordivine omnipotence and creative activity: as the immanent causes of theirperceptual states, they are at least quasi-creators, if not full creators.

Leibniz is not the only idealist philosopher in the period to take up the‘mirror of God’ theme; Berkeley is clearly inspired by the same theme when heintroduces a modified version of occasionalism in his published writings.Berkeley, of course, has no problem in adopting an occasionalist stance withregard to sensible things such as tables and chairs where these are understoodin immaterialist terms; indeed, in his early notebooks he was prepared to be afull-blooded occasionalist. But the mature Berkeley is not prepared to be anoccasionalist with regard to finite spirits, for as Philonous puts it in the ThreeDialogues, ‘I have in me an active thinking image of the Deity’ (DHP III, LJ 2232). For this reason among others, Berkeley ascribes genuine causality tofinite spirits in imagination and voluntary physical movement. I argue that hisposition on spirits is incoherent on the ground that, according to immaterial-ism, all changes in our bodies, as sensible things, are caused by God. However,in an important article, Jeffrey McDonough has recently come to Berkeley’sdefence by invoking the traditional doctrine of divine concurrence; thisdoctrine allows a sense in which both God and finite spirits can play a genuinecausal role.9 McDonough’s elegant paper is a striking instance of how

8 For revisionist readings of Hume on causality, see Galen Strawson, The Secret Connexion:Causation, Realism, and David Hume (Oxford: Clarendon Press, 1989) and John P. Wright,The Sceptical Realism of David Hume (Manchester: Manchester University Press, 1983).

9 Jeffrey McDonough, ‘Berkeley, Human Agency, and Divine Concurrentism’, Journal of theHistory of Philosophy 46 (2008), 567–90.


6 Introduction

knowledge of traditional theological doctrines can be used to defend earlymodern philosophers against the charge of incoherence launched from ananalytic perspective.

MIND: INTENTIONALITY AND IDEAS

Descartes’ teachings about causality may have been insufficiently radical; hefailed to take up the issue of whether Scholastic assumptions about causalityhad any real role to play in terms of the new mechanistic approach to thephysical world. The same sort of charge, however, cannot be brought againstDescartes’ theory of mind and ideas; it is Descartes who breaks decisively withthe Aristotelian conception of the soul as a principle of life and, as it were,domesticates the traditional term ‘idea’ so that it comes to denote the objectsof the human mind in thinking, and even on some accounts the thoughts oracts of thinking themselves. Before Descartes, by contrast, the term ‘idea’ wasemployed by early Christian philosophers to denote archetypes in the divinemind.But Descartes’ new conception of mind and ideas raised problems which

were to be taken up by Malebranche and Locke. Once again it is Malebranchewho is the pivotal figure; his position is not only distinctive in itself but throwsthe views of Leibniz and Locke into relief. On the face of it, Malebranche hastwo main objections to the Cartesian revolution in this area of philosophy. Inthe first place, Malebranche resists Descartes’ tendency to embrace what maybe called a ‘dustbin theory of the mind’. On this interpretation Descartesproposes an austere new criterion of the physical, and anything which doesnot satisfy this criterion is classified as mental: pains, tickles, hunger sensa-tions, concepts of God and triangles are all thrown into the mental dustbin. Ithas recently been argued by Nolan andWhipple that Descartes does not in factsubscribe to such a theory;10 I remain unconvinced, but in any case, whateverthe truth on that matter, we can make the best sense of Malebranche bysupposing that he implicitly ascribes just such a view to Descartes. In oppos-ition to the dustbin theory of the mind, Malebranche may be read as seeking toinsist that not everything that fails to qualify as physical (by a criterion of thephysical that he himself endorses) is thereby mental. The objects of thought—ideas or concepts—are third-realm entities in logical space; such ideas areinvolved not just in abstract thought but also in sense-perception of thephysical world. Since God is the locus of ideas, we encounter here the rootsof Malebranche’s doctrine, so ridiculed by Locke, that we see all things in God.

10 Lawrence Nolan and John Whipple, ‘The Dustbin Theory of Mind: A Cartesian Legacy?’,Oxford Studies in Early Modern Philosophy 3 (2006), 33–55.


Introduction 7

The other main target of Malebranche’s attack on Descartes’ philosophy isthe apparent Cartesian tendency to treat intentionality as a mark of themental. Such a tendency seems to be implicit in Descartes’ use of the term‘idea’ to denote all the items in the mind. Sensations, for Malebranche, unlikethoughts and perceptions, are not directed to an object; they are not of orabout anything, but are rather just blank effects. On this account it seems thatMalebranche has the resources, if only he will exploit them, to part companywith Descartes’ doctrine of the beast-machine. For Descartes, sensations andsense-perceptions are confused modes of thinking; they would not arise in themind if it did not have a faculty of pure intellect. Thus Descartes could notascribe sensations and sense-perceptions to animals without also ascribing tothem such a faculty. To the extent that Malebranche, by contrast, admits afaculty of pure intellect, he holds that it is involved in the apprehension ofconcepts or ideas but not in sensation or the non-intellectual component ofsense-perception. Thus Malebranche could coherently claim that animals havesensations. Malebranche, however, does not develop this view partly fortheological reasons; he is committed to the Augustinian principle that undera just God no innocent creature suffers misery. Such a principle would beviolated if animals, which are not corrupted by the Fall, were to suffer pain.

My view that Malebranche challenges the Cartesian revolution in thephilosophy of mind in these two main respects has been contested by somescholars; that is, commentators have argued that ideas, for Malebranche, arenot logical concepts and that he does ascribe intentionality to sensations.11

One issue that complicates the scholarly debate is the development, in thecourse of a long philosophical career, of his thinking about ideas and mind.Perhaps the most striking of Malebranche’s innovations in this area is thedoctrine of efficacious ideas. The doctrine seems to be motivated, in part atleast, by the desire to offer a more rigorous interpretation of the patristic thesisthat the mind is a merely ‘illuminated light’, deprived of all genuine cognitiveresources of its own. In the early Search After Truth Malebranche followsDescartes in holding that the mind is endowed with a faculty of pure intellect;it is by means of this faculty that it apprehends the ideas that God displays toit. By contrast, in later works such as the Dialogues on Metaphysics Male-branche comes to hold that ideas in God directly cause intellectual perceptionsand even sensations in the human mind. In the words of one French commen-tator, a doctrine of vision en Dieu gives way to a doctrine of vision par Dieu.But if ideas in God have causal properties, then it is difficult to see how they

11 For a denial that ideas for Malebranche are logical concepts see Andrew Pessin, ‘Male-branche on Ideas’, Canadian Journal of Philosophy 34 (2004), 341–86. For criticism of the thesisthat intentionality is not a mark of the mental for Malebranche see Alison Simmons, ‘Sensationin a Malebranchean Mind’, Jon Miller (ed.), Topics in Early Modern Theories of Mind: Studies inthe History and Philosophy of Mind (Dordrecht: Springer, 2009), pp. 105–29.


8 Introduction

can be logical concepts; for logical concepts are abstract entities, and abstractentities seem to be incapable of causing anything. Thus it is possible that theinterpretation according to which ideas are logical concepts is faithful to theearlier account but not to the later one.Descartes’ philosophy of mind was attacked not only by Malebranche but

also, more famously, by Locke. It is generally granted of course that Locke’sphilosophy in this area is anti-Cartesian in character, but the systematic natureof his opposition to Descartes has not been well understood. Thus there hasbeen a certain tendency to view Locke as mounting a series of sporadic raidson Cartesian dogmatism in the name of defending common sense; it issupposedly in this spirit alone that Locke attacks the beast-machine doctrineand the thesis that the mind always thinks. It is true that, especially in theEssay, Locke himself encourages the reader to understand his intentions in thisway; thus throughout his polemics he adopts the pose of the plain man who isnot afraid to point out that Descartes’ dogmatism flies in the face of observa-tion and experience. But Locke’s adoption of this pose often masks deeper,more controversial ambitions, and this is indeed what we find in the presentcase. As the evidence of his journals shows, Locke’s polemics in this areacontribute to the larger purpose of undermining Descartes’ immaterialisttheory of mind; they also attack the view that immateriality and naturalimmortality necessarily stand and fall together. Thus the conventional wisdomgoes wrong on two counts: not merely does it fail to do justice to Locke’smetaphysical and theological interests, but it fails to appreciate the unity ofpurpose that underlies the polemics.There is a further case in which the systematic nature of Locke’s opposition

to Descartes has not been appreciated: this is the topic of abstract ideas. Eversince the publication of the Principles of Human Knowledge there has been atendency for commentators to focus on the issue of whether Locke’s theory ofabstract ideas is vulnerable to Berkeley’s criticisms; thus scholars have oftendebated whether it is really true that Locke is committed by his theory tosaying that abstract ideas combine inconsistent features. I argue that such anarrow focus on this issue does Locke a disservice; it diverts our attention fromthe role that the theory of abstract ideas plays in the overall argumentativestrategy of the Essay. And once we redirect our attention in this way we findthat the doctrine serves as a rather systematic replacement for the Cartesiantheory of innate ideas. Again, as we have seen in the case of Leibniz’s Discourseon Metaphysics, such a shift of emphasis is not incompatible with a moretraditional approach: there is of course no reason why we should not continueto debate the issue of whether Locke’s theory succumbs to Berkeley’s criti-cisms. But if our interest lies (as it surely should do) in understanding Locke’spositive epistemology, then the change of focus is clearly necessary; it is interms of his theory of abstraction that Locke seeks to execute his project ofshowing how we can give an account of scientia or universal necessary


Introduction 9

knowledge without appealing to innate ideas. As Locke writes, ‘all generalKnowledge lies only in our own Thoughts, and consists barely in the contem-plation of our own abstract Ideas’ (Essay IV.iii.6).The history of philosophy has become more historical in recent decades,

since it has been concerned, inter alia, with the historian’s project of tellingaccurate narratives. But the question with which historians of philosophy areconstantly confronted today is whether in the process of becoming morehistorical the history of philosophy has shed its philosophical character. It iscertainly true that the new historians of philosophy no longer feel the trad-itional defensive urge to justify their enquiries by making past philosophersspeak directly to current debates; indeed, such deliberate attempts to enlistdead philosophers in a conversation with our contemporaries at Oxford orPrinceton are often, and rightly, viewed with suspicion. But to say this is not tosay that the impulse to seek continuity is entirely dead. Thus, the very act oftaking seriously seventeenth-century debates that were formerly dismissed orconsigned to the margins allows us to see that the participants were in factaddressing issues that have an important afterlife; Leibniz’s critique of Male-branche’s occasionalism, as we have seen, emerges as a contribution to adebate over whether the real task of science or natural philosophy is to seeklaws or causes. Thus Malebranche’s attack on a cause-based account ofscientific endeavour stands in roughly the same relationship to, say, Russell’s‘On the Notion of Cause’ as Berkeley’s idealism stands to the modern linguisticphenomenalism of A.J. Ayer. To insist on the reality of such connections is notto say that we should seek to dismiss the theological motivation and evenformulation of the arguments in each case as of no account; to do so is tosubstitute a dull, lifeless caricature for a flesh-and-blood historical figure.Analogously, it would be misguided to draw attention to the existence ofclass conflict in the English civil war while insisting that the religious ideasof the participants were mere fluff.

But there are other ways in which we may allow the history of philosophy tohelp us in our contemporary debates. Many years ago, in an influential paperIan Hacking wrote that he was ‘afflicted by a conjecture, both unsubstantiatedand unoriginal, that the space of a philosophical problem is largely fixed by theconditions that made it possible’.12 The conditions for the emergence of theconcepts in terms of which a philosophical problem is formulated almostembarrassingly determine what can be done with them. In his view modernpositions in the philosophy of mathematics—Platonism, constructivism, logi-cism, and the like—re-enact conceptual moves which were determined by anancient and alien problem-situation: the breakdown of the concept of the

12 Ian Hacking, ‘Leibniz and Descartes: Proof and Eternal Truths’, in Anthony Kenny (ed.),Rationalism, Empiricism, and Idealism (Oxford: Clarendon Press, 1986), p. 48.


10 Introduction

traditional Aristotelian concept of scientia in the seventeenth century.13 Thephilosophy of mathematics is not my topic in this collection, but Hacking’smessage is highly relevant to themes that are discussed. In the spirit ofHacking I suspect that contemporary philosophy of mind, while stoutlyrejecting substance dualism, takes over uncritically the Cartesian conceptionof what items should be classified as mental. Modern philosophers of mindhave often failed to see that the classification is itself driven by what Hackingcalls an alien problem-situation; the problem in question is what accountshould be given of all those items that do not qualify as physical by the austerecriterion introduced by Descartes. Descartes’ own conception of the essence ofbody or matter as extension has itself gone the way of the dodo and thedinosaur, but his account of what items should be classified as mental lingerson. There is thus arguably a therapeutic role for the history of philosophy toplay: coming to terms with the entirely contingent origins of our modernconcepts may be a necessary condition of making progress in philosophy. Inthe words of Ian Hacking, the ‘flybottle’ was shaped by prehistory, and onlyarchaeology can display its shape.14

13 Hacking, ‘Leibniz and Descartes’, p. 60.14 Hacking is of course alluding here to Wittgenstein’s dictum that his aim in philosophy is to

show the fly the way out of the flybottle.


Introduction 11

1

Scientia and Self-Knowledge in Descartes

In The Search After Truth and related writings Malebranche strongly criticizesDescartes’ thesis that the nature of the mind is better known than the nature ofbody. In opposition to his mentor Malebranche maintains that whereas wehave a clear idea of body, we have no such idea of the mind; we know the mindonly by consciousness or internal sensation. In the last twenty years or soMalebranche’s critique of Descartes in this area has attracted a good deal ofmostly favourable attention, and especially if we stand back a little from thetexts, it is not difficult to see why.1 Descartes gave the world a science of bodywhich is a recognizable ancestor of Newtonian physics; even if Descartes’ ownphysics was seriously flawed, he was right in thinking that a science of thephysical world was possible. By contrast, Descartes produced no comparablescience of the mind. In this area all Descartes can offer, it seems, is the kind ofrational psychology the weaknesses and illusions of which were devastatinglyexposed by Kant in the Transcendental Dialectic of the Critique of PureReason. Indeed, it has been plausibly argued that Malebranche’s critique ofDescartes is a precursor of Kant’s demolition work. Whatever his own inten-tions may have been, Malebranche was in effect engaged in underminingrational psychology from within.2

The view that Malebranche has the better of the debate with Descartes hasnot gone unchallenged; indeed, recently there have been signs of a backlash.Although, to my knowledge, no one has yet sought to rehabilitate Descartes’thesis that the nature of the mind is better known than the nature of body,some scholars have argued that Descartes was at least entitled to claimepistemic parity in this area.3 Nolan and Whipple, in particular, are even

1 See C.J. McCracken, Malebranche and British Philosophy (Oxford: Clarendon Press, 1983),pp. 76–81; T. Schmaltz,Malebranche’s Theory of the Soul: A Cartesian Interpretation (New York:Oxford University Press, 1996); N. Jolley, The Light of the Soul: Theories of Ideas in Leibniz,Malebranche, and Descartes (Oxford: Clarendon Press, 1990) and chapter 5 in this volume.

2 A. Pyle, Malebranche (New York and London: Routledge, 2003), p. 186.3 L. Nolan and J. Whipple, ‘Self-Knowledge in Descartes and Malebranche’, Journal of the

History of Philosophy 43 (2005), 55–82; A. LoLordo, ‘Descartes and Malebranche on Thought,Sensation, and the Nature of the Mind’, Journal of the History of Philosophy 43 (2005), 387–402.


prepared to defend this claim with reference to the concept of scientia thatultimately derives from Aristotle. On their view Descartes claims—justifiablyon his principles—that he had achieved scientia with regard to mind as well asbody.My aim in this essay is not to rehearse the case for Malebranche’s critique of

Descartes but rather to challenge the understanding of Descartes’ position onwhich such recent defences of Descartes rely. The idea of framing the discus-sion in terms of the concept of scientia is a good one, but I believe that theinterpretation offered by Nolan and Whipple, and to some extent LoLordo,cannot be sustained. In the first part of the essay I argue that Nolan andWhipple give a mistaken account of Cartesian scientia; contrary to theirclaims, the Cartesian concept of scientia is a strong one that retains more ofits Aristotelian connotations than they allow. In the second and third parts ofthe essay I argue that there is no clear evidence that, for Descartes, theconditions for scientia are satisfied by his account of mind; moreover, it is amistake to lift Descartes’ claims about self-knowledge out of context and treatthem as final results of the system. In the concluding section of the essayI briefly examine the issue of whether, for Descartes, a scientia of mind is evenpossible. Throughout the essay I focus on Descartes’ position in the Medita-tions and related writings and ignore possibly complicating factors introducedby his final philosophical work, the Passions of the Soul.4

I

The concept of scientia derives from the Aristotelian tradition, and whateverelse is controversial, one thing is surely clear: though Descartes retains theterm ‘scientia’ for a particularly valuable and fruitful kind of knowledge, hedoes not retain the Aristotelian conception in its entirety. To understand thenature of Descartes’ break with Aristotle, consider the key components oftraditional Aristotelian scientia as they emerge from this helpful summarygiven by Pauline Phemister:

In the Posterior Analytics Aristotle stipulates that scientific knowledge is alwaysknowledge of what is universally true and it proceeds by necessary proposi-tions . . . Items of scientific knowledge can be demonstrated by syllogistic deductions

LoLordo revealingly remarks that ‘not much in Descartes’ system depends on our having betterknowledge of the mind than of the body’ (390).

4 For the issue of Descartes’ scientific ambitions for The Passions of the Soul, see T. Sorell,‘Morals and Modernity in Descartes’, in T. Sorell (ed.), The Rise of Modern Philosophy: TheTension between the New and Traditional Philosophies from Machiavelli to Leibniz (Oxford:Clarendon Press, 1993), pp. 273–88.


Scientia and Self-Knowledge in Descartes 13

from true premises which are a priori to us and better known than the conclusionand which contain within them the ‘cause’ or explanation of the conclusion . . .Thisprocedure enables us to understand the thing which is to be demonstrated, for itshows why the thing is the way it is and could not possibly be otherwise. We haveknowledge of a thing on thismodel whenwe know its necessary cause. Knowledge ofthe cause is provided by demonstration of the fact to be explained.5

Such a conception of scientiamay have held the stage throughout the medievalperiod, but it was increasingly challenged in the age of the Scientific Revolution.

How much of the Aristotelian conception of scientia Descartes rejectsmay be controversial, but certain things are surely not in doubt. In thefirst place, Descartes rejects the thesis that scientia necessarily involves dem-onstrating effects from causes. As Hacking says, the method employed bythe scientists and natural philosophers of the Scientific Revolution tended tobe hypothetico-deductive; practising scientists were increasingly engaged inpostulating causes to explain effects, and then deriving test implications fromthe hypotheses. Descartes may have tried to convince critics that this methodtoo was a kind of demonstration, but it is clearly not demonstration in thetraditional Aristotelian sense.6 Secondly, Descartes of course cannot acceptthat scientia involves syllogistic inference; no philosopher in the early modernperiod is more famous than Descartes for his hostility to the syllogism. Perhapsmisunderstanding its purely expository role in demonstration for Aristotle,Descartes objects that the syllogism is useless as an instrument of discovery.7

And there were other grounds for dethroning the syllogism from the prominentposition it had held for Aristotle. It had never been plausible to claim thatEuclidean proofs were syllogistic in form, yet in the early modern period suchproofs were widely regarded as paradigm examples of demonstration.

Descartes may have had more distinctively philosophical reasons of his ownfor rejecting other features of Aristotelian scientia. Consider Aristotle’s insist-ence that scientia is of universal and necessary truths. Whether Descartes canaccept the universality requirement is surely put in question by the cogito: ifthe cogito is indeed an ingredient of scientia, then scientia will include at leastsome singular propositions. And whether Descartes can accept the necessityrequirement is a more interesting question with wider ramifications. The issueis highly controversial, but arguably Descartes is prevented by his doctrine ofthe creation of the eternal truths from subscribing to this requirement. WhenDescartes insists on the dependence of the eternal truths on the divine will, he

5 P. Phemister, ‘Locke, Sergeant, and Scientific Method’, in Sorell (ed.), The Rise of ModernPhilosophy, p. 232.

6 See I. Hacking, ‘Leibniz and Descartes: Proof and Eternal Truths’, in A. Kenny (ed.),Rationalism, Empiricism, and Idealism (Oxford: Clarendon Press, 1986), p. 55.

7 On Descartes’ critique of the syllogism, see S. Gaukroger, Cartesian Logic (Oxford: Clar-endon Press, 1989). Gaukroger emphasizes Descartes’ criticism that the syllogism is useless as aninstrument of discovery.


14 Causality and Mind

can be read as denying that there are, strictly speaking, any necessary truths.Descartes seems to suggest such a reading when he writes to Mersenne of ‘themathematical truths which you call eternal’ (15 April 1630, AT I 145; CSMKIII 23); he thereby seems to distance himself from the thesis that there are anyeternal, that is, necessary truths. Some commentators of course have readDescartes as advancing a weaker thesis: although there are necessary truths,they are not necessarily necessary.8 At first sight such an interpretation isencouraged by a passage from a letter to Mesland:

And even if God has willed that some truths should be necessary, this does notmean that he willed them necessarily; for it is one thing to will that they benecessary, and quite another to will this necessarily, or to be necessitated to will it.

(2 May 1644, AT IV 118–19; CSMK III 235)

But as I have argued elsewhere, even here Descartes stops significantly short ofendorsing the thesis that there are necessary truths.9 He appears rather to bearguing concessively: even if it is granted that there are necessary truths, itdoes not follow that they are necessarily necessary. The stronger reading ofDescartes’ doctrine is in line with what we may regard as one of the mainmorals of the Cartesian revolution in philosophy—the shift away from modalclaims to epistemic ones.Descartes, then, has reasons stemming both from the science of his time and

from his own philosophy for not endorsing the full traditional Aristotelianconception of scientia. But what conception of scientia does he put in the placeof the traditional Aristotelian one? Nolan andWhipple have recently answeredthis question by saying: ‘Descartes consistently characterizes scientia as avariety of certainty that is grounded in knowledge of the existence and natureof Godwho guarantees that our intellectual faculty cannot but tend towards thetruth.’10 Such an interpretation seems to be encouraged by the enquirer’sreflection on his situation at the end of the Fifth Meditation. ‘Thus I see plainlythat the certainty and truth of all knowledge (scientiae) depends uniquely onmy knowledge of the true God, to such an extent that I was incapable of perfectknowledge about anything else until I knew him’ (AT VII 71; CSM II 49).But this account of Cartesian scientia is, I believe, open to challenge. In the

first place, it can be criticized on textual grounds. According to Nolan andWhipple, Descartes consistently invokes the divine guarantee in his character-izations of scientia. But this textual claim is not strictly accurate. In the unfin-ished French work The Search for Truth, for instance, Descartes’ spokesman,Eudoxus, speaks of acquiring ‘a body of knowledge (doctrine) which was firm

8 See E. Curley, ‘Descartes on the Creation of the Eternal Truths’, Philosophical Review 93(1984), 569–97. Cf. Hacking, ‘Leibniz and Descartes: Proof and Eternal Truths’, pp. 52–3.

9 Jolley, Light of the Soul, p. 51. Cf. H. Frankfurt, ‘Descartes on the Creation of the EternalTruths’, Philosophical Review 86 (1977), 36–57.

10 Nolan and Whipple, ‘Self-Knowledge in Descartes and Malebranche’, 63.



and certain enough to deserve the name “science” (science)’ (AT X 513; CSM II408). Here there is no explicit mention of the divine guarantee. But secondly,andmore importantly, Nolan andWhipple omit a condition that is stated in thequotation from the Search: scientia is a body of knowledge as opposed, say, to aset of isolated intuitions. This insistence on scientia as a body of knowledge isone of the features that arguably distinguishes scientia for Descartes from merecognition (cognitio); it also constitutes one important remaining link with theAristotelian tradition.

One weakness of the account offered by Nolan and Whipple is that, whileemphasizing the importance of the divine guarantee, it fails to grasp itspurpose; that is, it fails to recognize that God’s guarantee allows our knowledgeto become systematic. The point has been admirablymade by JohnCottinghamin his introduction to his edition of the Conversation with Burman:

The need for God in Descartes’s theory of knowledge, and the sense in which allknowledge can be said to depend on him, now begins to emerge. For although wecan have some knowledge without God (the knowledge of epistemically self-guaranteeing propositions), such knowledge would never, so to speak, get usanywhere. It would last only as long as the relevant proposition, or set ofpropositions, was actually being attended to. . . . Once we have arrived at theproposition that God exists and is not a deceiver, then at last the possibility ofdeveloping a systematic body of knowledge becomes available.

(CB xxxi–xxxii)

Notice that on this view the divine guarantee may not be built into the verydefinition of scientia; it may be rather that which explains essential features ofscientia such as firmness and systematicity. As we have seen, the divineguarantee is omitted from the definition of scientia in The Search For Truth.But whether we hold that the divine guarantee is built into the very definitionof scientia matters little: the important point is to understand its role orpurpose in Descartes’ epistemology.

Before we leave the issue of the nature of Cartesian scientia, we should noticeone further claim that Nolan and Whipple press: this is the alleged anti-formalism of Descartes’ conception of scientia. Following the lead given byHacking and others, Nolan and Whipple insist that it is a mistake to think ofscientia as a systematic body of knowledge on the traditional Aristotelianmodel.Scientia, for Descartes, is not an axiomatic system ‘in which the various parts ofknowledge bear complex entailment relations to one another’.11 On their view,Descartes is most interested in ‘unveiling the contents of our clear and distinctideas and thereby attaining knowledge’, and this ‘has nothing to do withdeducing theorems from axioms in the traditional sense, and everything to dowith removing prejudices so that these contents can be immediately intuited’.12

11 Nolan and Whipple, ‘Self-Knowledge in Descartes and Malebranche’, 61.12 Nolan and Whipple, ‘Self-Knowledge in Descartes and Malebranche’, 62.



Nolan and Whipple make some valuable points, but they seem to me to bein danger of conflating two questions. That is, they seem to run together theissue of whether scientia is necessarily a systematic body of knowledge with theissue of whether it must be conceived as a formal axiomatic system. Now thereis no doubt that Descartes is generally hostile to traditional formal logic; inparticular, as we have seen, he despises the syllogism because of its uselessnessas an instrument of discovery. But from the fact that scientia need not be aformal system for Descartes, it does not follow that it is not essentially asystematic body of knowledge; even if the truths in the system are deductivelylinked, it is still possible to give an account of such deduction that is non-formal. Moreover, even if for Descartes formal deduction plays no role in thediscovery of new truths, it does not follow that it plays no role in displaying thesystematic structure of such knowledge. And as Gaukroger says, this is the rolethat it plays in such a work as The Principles of Philosophy.13 Thus the issue ofDescartes’ anti-formalism seems irrelevant, or marginal at best, to the properunderstanding of his concept of scientia.An underlyingweakness of the Nolan andWhipple account is the exaggerated

and misleading insistence on Cartesian therapy. Like other commentators theystress thatDescartes seeks to offer a cure in theMeditations for the prejudices andpreconceived opinions which go back to childhood and to replace themwith theclear and distinct ideas of the intellect. Descartes’ interest in such epistemologicaltherapymay be real, but it should not lead us to underestimate his ambition to bethe new Aristotle. That is, Descartes is not just interested in showing us howto achieve exquisite states of certainty about our own existence and the existenceof God; he is interested, surely muchmore, in developing a new and true scienceof the physical world to replace the discredited Aristotelian one. As Cottinghamsays, Descarteswants to showus howour knowledge can get somewhere. Andweshould never forget that on the first page of the First Meditation—the workwhich is cited as primary evidence of Descartes’ concern with therapy—theenquirer explains his real ambitions and the goal of his whole enterprise:demolishing everything completely and starting again on new foundations isseen to be necessary ‘if I wanted to establish anything at all in the sciences(scientiis) that was stable and likely to last’ (AT VII 17; CSM II 12). Descartes ismore interested in being a natural philosopher than a psychotherapist.

I I

Scientia, for Descartes, is thus a systematic body of knowledge that is firmand certain and that is made possible by the divine guarantee. Now it is

13 Gaukroger, Cartesian Logic, p. 116.



uncontroversial that Descartes supposed his physics to satisfy the conditionsfor scientia; as we have seen, those features of the traditional Aristotelianconception that were problematic for the new science have been quietly (ornot so quietly) discarded by Descartes. To say that Cartesian physics satisfiesthe definition of scientia is not to say that the interpretation of the physicsraises no problems. Commentators have debated such issues as the role ofexperience—that is, observation and experiment—in Cartesian science andthe extent to which it is supposed to be a priori.14 One may also wonder howliterally we are supposed to take Descartes’ claim in correspondence that ‘myentire physics is nothing but geometry’ (27 July 1638, AT II 268; CSMK III119). But it is beside my purpose here to enter into such controversies. I shallsimply take it for granted that Cartesian physics is intended to be a paradigminstance of scientia. Of course, as I indicated in the introduction, we know thatCartesian physics is seriously flawed; Newton himself annotated his copy ofDescartes’ Principles of Philosophy by writing the word ‘error’ in the marginsover and over again. But the fact that we now know that Descartes’ physics isnot true—that in words attributed to Pascal it provides merely a romance ofnature15—is irrelevant to the issue of how Descartes viewed his achievement.There is thus supposed to be a Cartesian scientia of the physical world; is

there also be supposed to be a Cartesian scientia of the human mind? It is notdifficult to see how one could come to think that there must be. Descartes isfamous, or notorious, for his thesis that the mind is better known than body,and since Descartes clearly holds that he has developed a scientia of body, itmay well seem that he is committed to the thesis that there is a scientia of themind. Certainly Nolan and Whipple take such a view, for they write that ‘ourknowledge of the mind’s nature is at least on a par with our knowledge ofcorporeal nature’,16 and as we have seen, they offer a rather minimal charac-terization of Cartesian scientia as certain knowledge that is underwritten bythe divine guarantee.17 But it is, I suggest, a mistake to suppose that the thesisof the Second Meditation is relevant to the issue of whether, for Descartes,

14 For important discussions of Descartes’ science, see D. Garber, Descartes’s MetaphysicalPhysics (Chicago: University of Chicago Press, 1992) and ‘Descartes’ Physics’, in J. Cottingham(ed.), The Cambridge Companion to Descartes (Cambridge and New York: Cambridge UniversityPress, 1992), pp. 286–334; D. Clarke, Descartes’ Philosophy of Science (Manchester: ManchesterUniversity Press, 1982), Occult Powers and Hypotheses: Cartesian Natural Philosophy UnderLouis XIV (Oxford: Clarendon Press, 1989), and ‘Descartes’ Philosophy of Science and theScientific Revolution’, in Cottingham (ed.), Cambridge Companion to Descartes, pp. 258–85.

15 B. Pascal, Pensées, ed. A.J. Krailsheimer (Harmondsworth: Penguin, 1966), p. 356.16 Nolan and Whipple, ‘Self-Knowledge in Descartes and Malebranche’, 56.17 My concern in this article is primarily with Descartes’ view of his project, not with his

achievement, but it is worth noting that Nolan and Whipple offer characterizations of Descartes’procedure which are both misleading and too generous. For instance, they write not only of the‘res cogitans proof ’ in the Second Meditation but also of his discovery of further properties of themind a priori from our innate idea of the self (Nolan and Whipple, ‘Self-Knowledge in Descartesand Malebranche’, 65–6.) Such descriptions of Descartes’ procedure appear unwarranted. In the



there is a scientia with regard to the nature of the mind. As we shall see,Descartes is concerned here, not with scientia, but with an inferior or at leastless fruitful kind of knowledge.The fact that the thesis that the mind is better known than body is

introduced and defended in the Second Meditation is important, for eventhough it is defended elsewhere (for example, in the Fifth Replies), it needs tobe understood, not as a thesis within the final system, but rather in terms of thestage of the journey which the enquirer has reached. Remember that the laterpart of the Second Meditation has the goal of combatting twin empiricistprejudices—the view that we know bodies best of all and the view that bodiesare known through the senses. The enquirer is engaged in rehearsing argu-ments to rid himself of these prejudices once and for all. Moreover, we shouldnot expect Descartes to say that the enquirer is in possession of a scientia of themind. For at this stage the enquirer still lacks the divine guarantee; andwhether or not the divine guarantee is built into the very definition of‘scientia’, it is in some sense a necessary condition of such knowledge. Ofcourse it may be objected that there is logical space for a distinction betweennot having the divine guarantee at all and having the divine guarantee but notknowing that one has it. It might then be said that Descartes’ enquirer is in thesecond position and not the first. But as the discussion of the atheist geometershows, it seems that, for Descartes, having the divine guarantee essentiallyinvolves knowing that one has it—that is, knowing that God exists and wouldnot deceive us with regard to our clearest intellectual intuitions.We should adopt the same approach, I believe, to the Fifth Replies. Gas-

sendi famously and rather naturally objects that Descartes may well haveestablished that the existence of his mind is more certain than the existenceof body, but he has not succeeded in establishing the more important thesisthat the nature of the mind is better known than the nature of body (AT VII275; CSM II 192). Descartes responds to this line of objection in his own voice,but his response, I suggest, should still be seen as relativized to the stage thatthe enquirer has reached on his philosophical journey. It may be objected thatif this is what Descartes is doing, it is strange that he does not make the pointexplicitly; moreover, his response is most naturally read as a defence of a resultin the final system. But such objections are arguably insensitive to the text.First, consider Descartes’ impatient response to Gassendi’s demand for achemical investigation of the mind: ‘Nor do I see what more you expecthere’ (AT VII 359; CSM II 248, emphasis added), where the ‘here’ is areminder that the enquirer’s argument should be understood in context.Moreover, we should notice that a little earlier Descartes has given a muchmore explicit reminder to Gassendi that his arguments should be understood

Second Meditation, for instance, Descartes seems to me not to discover properties of the mind apriori but simply to appeal to the data of introspection.



in context—that is, in terms of the stage in his philosophical journey that theenquirer has reached in the Second Meditation. Descartes reminds Gassendithat he had said that insofar as he knew himself he was nothing other than athinking thing, and significantly adds: ‘This is all that I asserted in the SecondMeditation’ (AT VII 355; CSM II 245). It would be strange indeed if a fewpages later Descartes were to forget that the issue at hand is simply what theenquirer has come to understand at this point in the Second Meditation.

The fact that in the Second Meditation and related writings Descartes isconcerned with something less than scientia is confirmed by the evidence ofterminology. In all his statements of the thesis that the mind is better knownthan body Descartes consistently avoids using the term ‘scientia’. The title ofthe Second Meditation informs us simply: mind is notior than body (AT VII23; CSM II 16), and in the body of the meditation itself he summarizes hisresult by saying: ‘aperte cognosco nihil facilius aut evidentius mente posse ame percipi’ (AT VII 34; CSM II 22–3). The same avoidance of any reference to‘scientia’ is apparent in the Fifth Replies where Descartes defends his thesisagainst Gassendi by reference to the principle that we know something betterthe more attributes we know of it. The interpretation of this principle is notour present business, and we shall return to it; here our concern is with the factthat Descartes uses terms like ‘cognitio’ and ‘cognoscere’, not ‘scientia’:

But as for me, I have never thought that anything more is required to reveal asubstance than its various attributes, thus the more attributes of a substance weknow (cognoscamus), the more perfectly we understand its nature . . .The clearinference from this is that more attributes are known (cognosci) in the case of ourmind than in the case of anything else. For no matter how many attributes arerecognized (cognoscuntur) in any given thing, we can always list a correspondingnumber of attributes in the mind which it has in virtue of knowing the thing: andhence the nature of the mind is the one that is known best of all (notissima).

(AT VII 360; CSM II 249, translation modified)

The same avoidance of the term ‘scientia’ is found in the correspondingpassage from the Principles of Philosophy, the marginal summary of whichis: ‘Quomodo mens nostra notior sit quam corpus’:

In order to realize that our mind is known (cognosci) not simply prior to andmore certainly (certius) but also more evidently than body, we should noticesomething very well known by the natural light: nothingness possesses noattributes. It follows that whenever we find some attributes or qualities, there isnecessarily some thing or substance to be found for them to belong to; and themore attributes we discover in the same thing or substance, the more clearly dowe know (cognoscere) that substance. Now we find more attributes in our mindthan in anything else, as is manifest from the fact that whatever enables us toknow (cognoscamus) anything else cannot but lead us to a much surer knowledge(cognitionem) of our own mind.

(AT VIIIA 8; CSM I 196, translation modified)



It is tempting to emphasize that Descartes is not talking about scientia in suchpassages by translating ‘cognitio’ and its cognates by ‘acquaintance’; thus wemight read Descartes as saying that we have a much surer acquaintance withourmind than anything else. It is true that such a translationmight on occasionsound rather odd; it would give the reader a jolt to be told that ‘the moreattributes of a given substance we are acquainted with, the more perfectly weunderstand its nature’ (ATVII 360; CSM II 249). Tomy ear at least, the passagewould be less jolting if ‘perfectius’ were translated as ‘more completely’, as isindeed quite acceptable. And as we shall see, there are reasons why we shouldnot be too worried if this criterion of complete understanding sounds naive.But it would be a mistake to suggest that ‘cognitio’ can always be rendered as‘acquaintance’ if acquaintance is taken to involve non-propositional know-ledge. Consider, for instance, Descartes’ well-known discussion of the problemof the atheist geometer where hemakes one of his sharpest distinctions betweencognitio and scientia. Descartes writes of the atheist’s cognitio that the threeangles of a triangle are equal to two right angles; here the cognitio is obviouslypropositionally structured. Cottingham, Stoothoff, and Murdoch are probablyright to settle for the word ‘awareness’ in their translation:

The fact that an atheist can ‘clearly know that the three angles of a triangle areequal to two right angles’, I do not dispute. But I maintain that this awareness(cognitio) of his is not true knowledge (scientia), since no act of awareness thatcan be rendered doubtful seems fit to be called knowledge (scientia).

(AT VII 141; CSM II 101, translation modified)

Thus I shall not insist on the claim that, in the passages from the Fifth Repliesand the Principles, ‘acquaintance’may be a better translation than ‘knowledge’.The important point is that Descartes constantly uses terms which, unlike‘scientia’, have no connotations of systematic knowledge.Understanding thatDescartes’ reply toGassendi is relativized to the enquirer’s

stage in theMeditationsmay help us tomeet a well-known critique of Descartes’argumentative strategy in the Fifth Replies. Recall that Descartes famouslydefends the thesis that the mind is better known than body by appealing to theprinciple that the more properties of a substance we know, the more perfectly weunderstand its nature. Commentators have objected that this criterion of perfectknowledge is a simplistically quantitative one which is at odds with the overalltenor of Descartes’ philosophical system.MargaretWilsonmakes the point well:

For the predominant theme in his writings on knowledge of nature is that perfectcomprehension of material substance is obtained not by lengthening the list ofproperties (as Bacon’s program, for instance, demanded), but by providing anaccount of the extension, figure, and motion of body’s internal parts.18

18 M.D. Wilson, Descartes (London: Routledge and Kegan Paul, 1978), pp. 96–7.



Wilson further objects that Descartes’ application of the criterion in the FifthReplies leads him into an inconsistency with the main theme of the wax sub-meditation. For in explaining the application of the criterion in response toGassendi, Descartes gives a long list of sensory judgements about the piece ofwax; that is, he lists sensible qualities such as whiteness and hardness whichare identified through judgements based on sensory intake. By contrast, in thewax meditation itself, Descartes had located perfect understanding in ‘anintellectual perception of the essence of body’.19 Thus, according to Wilson,Descartes seems to have forgotten the very moral of the wax meditation.

It is possible to reply to Wilson’s first objection here by saying that there isindeed a sense in which the quantitative criterion of perfect knowledge is notthe criterion that Descartes endorses when expounding his system. But it doesnot follow from this that Descartes is at fault for not invoking the moresophisticated criterion in his response to Gassendi. For once we recognizethat Descartes’ reply to Gassendi is relativized to the enquirer’s stage in theSecond Meditation, we can see that he is stating a criterion that is appropriateto the enquirer’s level of philosophical enlightenment. Moreover, the criterionin question in the Fifth Replies is a criterion not of scientia but of cognitio.Thus, to the objection that Descartes does nothing to tell Gassendi that thecriterion in question is a simplistic one, we may concede the point, whileadding a qualification that effectively draws its sting: from the fact that it is asimplistic criterion of perfect scientia it does not follow that it is a simplisticcriterion of perfect cognitio. These two responses can, I think, be combined.The enquirer, at the stage of philosophical enlightenment he has reached inthe Second Meditation, does not yet grasp the nature of scientia and itsrelation to cognitio. Wilson has essentially made the mistake of confusingthe criteria of perfect scientia and the criteria of perfect cognitio.

Descartes’ appeal to the apparently simplistic criterion can thus bedefended. What of Wilson’s objection that the reply to Gassendi misrepresentsthe moral of the very meditation that it is supposed to be explaining anddefending? According to Wilson, as we have seen, in the original discussion ofthe piece of wax, Descartes identifies perfect comprehension with intellectualperception of the essence of body. At this point we stumble on the centralproblems of interpreting the wax meditation—a passage that has provokedwidely different readings, and we cannot do them full justice here. But it isarguable that Wilson reads too much into the wax meditation. Notice that herphrase ‘intellectual perception of the essence of body’ in effect combinesmetaphysical considerations (about the essence of body) and epistemologicalones (about how such essences are perceived). But it is worth recalling thatone of Descartes’ two main aims at this stage is simply to refute the naive

19 Wilson, Descartes, p. 97.



empiricist view that bodies are known through the senses. All he needs toestablish to that end is the epistemological thesis that bodies are perceivedthrough the intellect; it is the intellect, for example, that grasps that a body canremain the same through an infinity of changes in sensible qualities; at thisstage the reality of these qualities need not be called into question. Thus adefence of the core thesis about how bodies are known does not require anyclaim about the essence of bodies or how this essence is grasped. Wilson’scharge that the criterion of perfect knowledge which Descartes states anddefends in response to Gassendi is inconsistent with the teaching of theoriginal wax meditation arguably depends on reading back the final resultsof the system into the Second Meditation where they do not belong.

I II

So far I have concentrated on the Second Meditation and related writingsbecause it is here that Descartes introduces and defends the thesis that themind is better known than body. And though, as we have seen, they have notbeen prepared to defend the letter of his thesis, commentators who havesought to defend Descartes against Malebranche’s critique have also empha-sized those texts, or at least not discounted them. But it may be objected thatit is misguided to focus on such texts to the exclusion of others that are morerelevant; for what is at issue is the set of commitments of Descartes’ completedsystem. Thus we must look to the Sixth Meditation and the relevant sections inthe Principles of Philosophy where Descartes is expounding the final system.It is indeed necessary to look beyond the Second Meditation since, as I have

emphasized, this represents only a stage on the enquirer’s journey to fullphilosophical enlightenment. It cannot be denied that the enquirer makesepistemic progress between the Second and Sixth Meditations; in particular,he discovers that he has a divine guarantee for his clearest intellectualintuitions. But with regard to the issue of scientia the picture that emergeswhen we take a broader view is not significantly different. Even when theenquirer is nearing the end of his philosophical journey Descartes still avoidssaying that he has scientia of the mind or can achieve it. In the SixthMeditation the enquirer discovers that he has come to know God and himselfbetter (melius nosse) (AT VII 77; CSM II 54), and that he can achieve a clearand distinct idea of the mind and its real distinction from the body (AT VII78; CSM II 54), but even when underwritten by the divine guarantee clear anddistinct perception does not entail scientia. The same pattern is repeated inthe corresponding sections of the Principles of Philosophy where Descartes ismagisterially expounding the results of his system. Descartes explains howsubstances are known:



A substance is known (cognoscitur) through any attribute at all; but each sub-stance has one principal property which constitutes its nature and essence, and towhich all its other properties are referred. Thus extension in length, breadth anddepth constitutes the nature of corporeal substance; and thought constitutes thenature of thinking substance.

(AT VIIIA 25; CSM I 210, translation modified)

Thus what is at issue here is cognitio, not scientia.The claim that, for Descartes, there is no scientia of the mind may encoun-

ter some resistance. Critics are likely to point to the end of the Fifth Meditationfor evidence to the contrary. Here it might seem that Descartes is clearlycommitted to the claim that we can achieve scientia with regard to the natureof the mind. Consider not only the well-known statement at the end of theFifth Meditation that the divine guarantee is necessary for the achievement ofscientia but also the way in which the enquirer then follows it up. Here, byusing the term ‘knowledge’ throughout, the standard English translation byCottingham, Stoothoff, and Murdoch certainly encourages the idea that scien-tia is at issue in both sentences:

Thus I see plainly that the certainty and truth of all knowledge depends uniquelyon my knowledge of the true God, to such an extent that I was incapable of perfectknowledge about anything else until I knew him. And now it is possible for me toachieve full and certain knowledge of countless matters, both concerning Godhimself and other things whose nature is intellectual, and also concerning the wholeof that corporeal nature which is the subject matter of pure mathematics.

(AT VII 71; CSM II 49)

On the plausible assumption that human minds are included among theintellectual things here, it would indeed seem from this translation that Des-cartes is talking about the prospects for scientia throughout. But the translationis arguably misleading: consulting the Latin text shows that there is a switch interminology, for the second sentence reads:

Jam vero innumera, tum de ipso Deo aliisque rebus intellectualibus, tum etiam deomni illa natura corporea, quae est purae Matheseos objectum, mihi plane nota &certa esse possunt.

Descartes thus stops short of using the term ‘scientia’ to characterize theknowledge of God, intellectual things, and corporeal nature that the divineguarantee makes possible.

It is natural to object that in this passage, whatever we make of the switch interminology, Descartes clearly seems to place God, intellectual things, andcorporeal nature on the same epistemic footing. But this shows less than onemight expect. For Descartes’ point may be a rather limited one: once we are inpossession of the divine guarantee, an obstacle to the attainment of scientia isremoved across the board; whether the subject matter of our enquiry is God,



mind, or body, we no longer need to worry that our nature is defective and thatwe may be systematically deceived with regard to our clearest intellectualintuitions. To that extent God, intellectual things, and corporeal nature areindeed epistemically on a par. But to say this is not to say that scientia isequally attainable in all fields; for some of these areas of enquiry may be suchthat they do not lend themselves to the satisfaction of the systematicitycondition. The possession of divinely guaranteed intuitions or acts of aware-ness is a necessary condition for scientia, but is not a sufficient one.

The claim that, for Descartes, there is no scientia of the mind is also likely toencounter resistance from a related quarter. It is beyond dispute that one ofthe results of Descartes’ system is the discovery of the essence of the mind: thatessence is constituted by thought or cogitatio. And it may be supposed that ifDescartes holds that we can know the essence of mind, he must surely holdthat we can achieve scientia in this regard. Here the idea is that knowing theessence of x necessarily involves the ability to demonstrate non-trivial proper-ties of x in a way that yields the systematic knowledge which constitutesscientia. Such a reading is encouraged by Descartes’ famous discussion oftrue and immutable natures in the Fifth Meditation:

When, for example, I imagine a triangle, even if perhaps no such figure exists, orhas ever existed, anywhere outside my thought, there is still a determinate nature,or essence, or form of the triangle which is immutable and eternal, and notinvented by me or dependent on my mind. This is clear from the fact thatvarious properties can be demonstrated of the triangle, for example that itsthree angles equal two right angles, that its greatest side subtends its greatestangle, and the like.

(AT VII 64; CSM II 44–5)

To know the essence of the triangle thus involves the ability to demonstratethe properties that Euclid proves in the Elements. And no one would doubtthat Euclidean geometry has the systematic nature required for scientia.But the famous discussion of true and immutable natures is, I believe,

misleading with regard to Descartes’ general position; the geometrical case isin no way analogous to the case of the mind. When Descartes says that variousinteresting properties follow from the essence of the triangle, he is invoking athick concept of essence that includes not just the definition but the axiomsand even postulates of Euclidean geometry; the properties to which he appealsdo not follow from the essence of the triangle taken more strictly as thedefinition. But when Descartes says that we know the essence of the mind,he is not saying that we have epistemic access to an essence in the sense heinvokes in the geometrical case. In the case of the mind there is nothingcomparable to the axioms and postulates of Euclidean geometry. And in theabsence of such further propositions to serve as premises, there is no prospectfor the demonstration of non-trivial properties that scientia would require.



IV

There is thus no clear evidence that Descartes claims to be in possession of ascientia of mind. If this conclusion is correct, then it naturally prompts thequestion whether Descartes is committed to holding that the search for scientiain this area is misguided in principle. In favour of this claimwemay cite the factthat in the Fifth Replies Descartes criticizes Gassendi for demanding a chemicalinvestigation of the nature of the mind; he seems to suggest that Gassendi’sdemand is inappropriate as well as question-begging. And it is at least instruct-ive to note a feature of the subsequent controversy between Malebrancheand Arnauld; Arnauld, who is in general a reliable proxy for Descartes himself,rebukes Malebranche for demanding the impossible when he criticizes Des-cartes for mistakenly claiming to be in possession of a clear idea (i.e. scientia) ofthe mind.20

It is tempting to mount a very simple argument to show why Descartesmight think a scientia of the mind is impossible. It might be argued that thereare two necessary conditions of the possibility of a scientia of the mind thatDescartes is unable to satisfy, at least if scientia involves systematicity: first,determinism and secondly, complexity of mental structure.21 These conditionscannot be satisfied in Descartes’ philosophy, for Descartes is a libertarian whois committed to the existence of contra-causal freedom, and he is a dualist whoupholds the doctrine of the simplicity of the soul.

But this argument is too quick: it is vulnerable to two distinct kinds ofcriticism. One may question not only whether Descartes in fact holds the viewsthat are ascribed to him here, but also whether the allegedly necessary conditionsof a scientia of the mind are in fact necessary. In the first place, Descartes’position on the issue of free will is controversial; although he has been tradition-ally read as a libertarian, some recent commentators have argued that there isnothing in the texts which is inconsistentwith soft determinism. Secondly, itmaybe a mistake to suppose that complexity of mental structure can be understoodonly on a materialist model of the mind; although it is obviously consistent withsuch a doctrine, it does not seem to entail it. Leibniz indeed offers an instructiveexample of a philosopher who upholds the simplicity of the soul while alsoinsisting on the complexity of mental structure; for Leibniz, the mind has acomplex structure inasmuch as it has an infinity of petites perceptionswhich serveto ground its dispositional properties.22 Thus it seems possible to grant that

20 A. Arnauld, On True and False Ideas, ed. S. Gaukroger (Manchester: Manchester Univer-sity Press, 1990), ch. 23, p. 175.

21 See Pyle, Malebranche, p. 188; Nolan and Whipple, ‘Self-Knowledge in Descartes andMalebranche’, 76.

22 In the Preface to the New Essays on Human Understanding Leibniz stresses the parallelsbetween physics and ‘pneumatology’ (A VI.vi; RB 56); both sciences postulate unobservables—insensible corpuscles in physics and petites perceptions in the case of ‘pneumatology’.



complexity is a necessary condition of a scientia of the mind while also holdingthat the complexity is not precluded by a commitment to an immaterialist theoryof the mind. Now Descartes, of course, does not have the Leibnizian doctrine ofpetites perceptions, but he at least shares with Leibniz a commitment to the thesisthat the mind has dispositional properties—the activation of which results inoccurrent mental states. And this may be all that he needs.Whether Descartes is committed to determinism and complexity of mental

structure may be disputed, but even if he is not, it might still be argued that thereis room in his philosophy for acknowledging the possibility in principle of a kindof scientia of the mind. Once again it is instructive to consider one of Descartes’successors.Malebranche, for example, seems to hold that a scientia of themind ispossible at least in principle while denying both determinism and complexity ofmental structure. Such a scientiawould not of course be a predictive science, butas Malebranche observes, it would involve the ability to know a priori themodifications of which the mind is capable and the true relations betweenmental states. In other words, such a scientia would be closer to geometry thanto physics. It is not obvious that Descartes has the resources to rule out thepossibility in principle of a scientia of themind conceived on this model.What isclear, however, is that it could not take quite the form that it does in Male-branche. For whenMalebranche explicates the possibility at least in principle ofa scientia of the mind, he does so in terms of an idea of themind in God which islogically prior to his will; this idea is supposed to be an eternal archetype orblueprint for creation. It is this idea that God has withheld from human beingswith the result that we can never achieve scientia of the mind. But Descartes’insistence on the strict simplicity of God—a simplicity so strict that there is nodistinction between his intellect and his will—precludes him from thinking ofthe possibility of scientia of mind in these Malebranchian terms.Yet it would be wrong to end by simply emphasizing the distance between

Malebranche andDescartes. For themoral of the essay is in a sense that Descartesmay be closer toMalebranche on the basic issue than has been realized. Indeed, atleast before the Passions of the Soul, Descartes can agree with Malebranche thatwhile we possess a science of bodywe possess no science of themind. The fact thatthis point of kinship has not been recognized may arguably be blamed, at least inpart, on Malebranche himself. For while Malebranche was absolutely right toargue that Descartes gives us no scientia of themind, he failed to see that this maynot have been Descartes’ ambition; in particular, he failed to see that such scientiaof the mind was not at issue in Descartes’ defence of the thesis that the mind isbetter known than body. To this extent, and to this extent only, those who findfault with Malebranche’s critique of Descartes may be justified.23

23 An earlier version of this essay was read to a Philosophy Department colloquium at RiceUniversity. I am grateful to the audience, and to Mark Kulstad in particular, for helpfulcomments.



2

Descartes and the Action of Body on Mind

Contemporary writers have displayed a refreshing scepticism with regard tothe old ‘scandal’ of Cartesian interactionism. Louis Loeb, in particular, haschallenged the traditional idea that there is an internal inconsistency inDescartes’ system on this issue.1 Loeb’s strategy is to analyse Descartes’teaching concerning causality, and show that, properly understood, it doesnot preclude mind–body interaction. Such a strategy seems correct, butI believe that Loeb’s defence is not adequate as it stands; for Descartes’ positionis complicated not only by his claim that reality admits degrees but also by hiskey distinction between the formal and objective aspects of ideas. In this essayI shall argue that, even when these complications are recognized, Descartes’position emerges largely unscathed; at most his causal principle is a source oftrouble only for a strong version of interactionism. Contrary to the tendencyof much modern discussion, I shall focus exclusively on the causation ofmental events by bodies, for as we shall see, there is reason to believe thatthis is the real test case for the internal coherence of Cartesian interactionism.

I

Those who are shocked by the scandal of interactionism are not always veryclear just what the scandal is supposed to be. Mind–body interaction is

1 Louis E. Loeb, From Descartes to Hume: Continental Metaphysics and the Development ofModern Philosophy (Ithaca and London: Cornell University Press, 1981), pp. 134–49. For arather different challenge to the traditional view, see Robert C. Richardson, ‘The “Scandal” ofCartesian Interactionism’,Mind 91 (1982), 20–37. The views of Loeb and Richardson have beencriticized by Daisie Radner in ‘Is There a Problem of Cartesian Interaction?’, Journal of theHistory of Philosophy 23 (1985), 35–49. See also Robert C. Richardson, ‘Union and Interaction ofBody and Soul’, Journal of the History of Philosophy 23 (1985), 221–6, Louis E. Loeb, ‘Is There aProblem of Cartesian Interaction?’, Journal of the History of Philosophy 23 (1985), 227–31, andDaisie Radner, ‘Rejoinder to Richardson and Loeb’, Journal of the History of Philosophy 23(1985), 232–6.


rumoured to be unintelligible, but as it stands, this is a vague accusation. Whencritics try to explain it, they usually appeal to the fact that in Descartes’metaphysics mind and body are much too unlike for causal flow betweenthem. As Loeb remarks: ‘It is somewhat shocking to see such objections raisedafter Hume, without any attempt to reinstate the notion that there must besome specific degree of qualitative similarity between cause and effect.’2 Thepuzzling quality of such objections, however, helps us to identify the real natureof the accusation. Cartesian interactionism is scandalous, not because it shockscontemporary intuitions about causality, but because it flouts Descartes’ ownteaching on the subject. In particular, Descartes is supposed to subscribe to aversion of the causal likeness principle which precludes interaction betweensubstances as heterogeneous as mind and body. Yet, as Loeb also points out,Descartes does not in fact impose this particular restriction on causal relations.3

Although in the Conversation with Burman Descartes reportedly endorses thecommon axiom: ‘the effect is like the cause’ (AT V 56; CB 17), he nowherestates that they must be alike in essence. Indeed, in a letter to Clerselier, heexplicitly repudiates the suggestion that the diversity in nature of mind andbody poses any kind of problem for interaction (AT IXA 213; CSM II 275).Descartes does not have a causal likeness principle if this is taken to imply

that cause and effect are alike in essence.4 But he does make a number ofstatements which, obscure as they are, seem to impose some other restrictionon causal relations:

(1) It is manifest by the natural light that there must be at least as much realityin the efficient and total cause as in the effect of that cause. (AT VII40–1; CSM II 28)

(2) The fact that ‘there is nothing in the effect which was not previouslypresent in the cause, either in a similar or in a higher (eminentiori) form’is a primary notion which is as clear as any that we have. (AT VII 135;CSM II 97)

(3) Whatever reality or perfection there is in a thing, is present either formallyor eminently in its first and adequate cause. (AT VII 165; CSM II 116)

(4) It is certain that there is nothing in an effectwhich is not contained formallyor eminently in its EFFICIENT and TOTAL cause. (To Mersenne, 31December 1640, AT III 274; CSMK III 166)

(5) . . . there can be nothing in the effect which was not previously present inthe cause. (ToHyperaspistes, August 1641, AT III 427–8; CSMK III 192)

2 Loeb, From Descartes to Hume, p. 137.3 Loeb, From Descartes to Hume, p. 140.4 Perhaps the nearest that Descartes comes to stating a commitment to the causal likeness

principle is in the Comments on a Certain Broadsheet (AT VIIIB 359; CSM I 304); here Descartesargues that even sensory ideas are innate from the premise that there is no likeness between suchideas and corporeal objects. Even here, however, Descartes does not explicitly say that cause andeffect must be alike in essence.


Descartes and the Action of Body on Mind 29

These statements raise an obvious difficulty which is exacerbated by theobscurity of the Scholastic terminology in which they are couched. Thedifficulty is to decide whether they are all intended to come to the samething. Superficially, it is tempting to suppose that we are confronted by atleast two non-equivalent principles here. Statements (2) through (5) all sug-gest that the effect must somehow pre-exist in the cause; one might infer, then,that Descartes is committed to the principle that if the effect is F, the causemust also be F. Radner goes further: she suggests that Descartes is committedto a stronger thesis which she terms the communication principle: in causaltransactions a property-instance is communicated or transferred by the causeto the effect rather in the way that a baton is passed on from runner to runnerin a relay race.5 However, neither of these requirements seems to be imposedby (1). To say that the cause must contain at least as much reality as the effectcertainly does not imply that anything need be communicated by the cause tothe effect. Indeed, it does not even seem to entail that if the effect is F, the causemust also be F.

We can bring the problem to a sharp focus by concentrating on one ofDescartes’ hand-picked examples of causality. In his first proof of the existenceof God in the ThirdMeditation Descartes concludes that his idea of God can becaused by nothing less thanGod himself (ATVII 45; CSM II 31). Here, then, wehave a cause which is an infinite substance, and an effect which is a mode of afinite substance. Just how degrees of reality are to be measured in Descartes’philosophy is a controversial issue to which we must return, but for the presentit does not matter. By any standard of reality that Descartes is likely to adopt, itis clear that God has it to a maximum; there is no doubt that the cause herepossesses at least as much reality as the effect; thus (1) is obviously satisfied. Butit might be objected that in this case we have something in the effect which doesnot pre-exist in the cause. For the effect is not only finite, it is also a mode; andneither finitude nor modes can be predicated of God. Thus it might be arguedthat (2) through (5) are not satisfied in this case.

The temptation to suppose that we are confronted by more than oneprinciple should, nonetheless, be resisted. What scrutiny of (2) through (5)suggests is that the pre-existence requirement is weaker than it appears to be,for it is hedged around with a significant qualification: Descartes allows thatthe effect may inhere ‘eminently’ in the cause. The concept of eminence iscrucial, but it is of course obscure. Kenny helpfully suggests that to possess aproperty ‘eminently’ is not to possess F itself but rather to possess somegrander property G.6 An uncontroversial illustration would be the following.

5 Radner, ‘Is There a Problem?’, esp. 41. This claim is essential to her defence of the traditionalview that Cartesian interactionism is incoherent.

6 Anthony Kenny, Descartes: A Study of his Philosophy (New York: Random House, 1968),p. 141.



Suppose we assume that being six feet tall is a grander property than being fivefeet tall; a six-footer may then be said to possess eminently the property ofbeing five feet tall. Fortunately, the application of the concept of eminence toDescartes’ own example of the idea of God seems equally straightforward. Godis not finite nor is he a mode, but he possesses these properties eminentlyinasmuch as he has the grander properties of infinity and substantiality. Thuswhen Descartes’ qualification concerning eminence is taken into account, thedivine origin of the idea of God no longer constitutes a counterexample to theprinciple that whatever is in the effect must pre-exist in the cause. It is true thatthis qualification is missing in the case of (5), but it is natural, I think, tosuppose that this is simply an imprecise statement of a principle expressed in(2) through (4).7

On the proposed interpretation, then, Descartes is not committed to thecommunication principle: to say that God is ‘eminently’ finite and ‘eminently’ amode is not to say that he communicates or transfers these properties tothe idea in Descartes’ mind. Moreover, and more controversially perhaps,the proposed interpretation implies that Descartes is not committed to theprinciple that if the effect is F, the cause must also be F. As we have seen, theeffect can inhere eminently in the cause, and to possess a property eminentlyis not to possess the property itself. Thus once the eminence qualification isintroduced, the pre-existence claim is deprived of most of its sting: indeed, itseffect is to collapse (2) through (5) into (1).8 It remains to give a name to thisprinciple, and since talk of causal likeness is misleading, I propose to followJohn Cottingham and speak of the Causal Adequacy Principle.9

II

Ever since Descartes’ own time, his readers have found the Causal AdequacyPrinciple obscure. For the principle implies that reality admits of degrees, andcritics have wanted to know how this could be the case. When Descartesis challenged by Hobbes on precisely this point, he is brusque in his reply,but he does offer some help: he indicates that his criterion is in some senseindependence:

7 Radner, ‘Is There a Problem?’, 44, holds that Descartes is committed to the pre-existenceprinciple by virtue of his (alleged) commitment to the communication principle.

8 This agrees with Loeb, ‘Is There a Problem of Cartesian Interaction?’, 228. Cf. KennethClatterbaugh, ‘Descartes’ Causal Likeness Principle’, Philosophical Review 89 (1980), 381: ‘Des-cartes formulates his causal likeness principle in several ways, all of which are intended tocapture the same necessary condition for efficient causality.’

9 J. Cottingham, Descartes (Oxford: Blackwell, 1986), p. 49. Cf. Bernard Williams who speaksof the Adequate Reality Principle, Descartes: The Project of Pure Enquiry (Hassocks: Harvester,1978), p. 143. Other writers (e.g. Radner) speak of the ‘at least as much’ principle.



I have made it quite clear that reality admits of more and less. A substance is more athing than amode; if there are real qualities or incomplete substances, they are thingsto a greater extent than modes, but to a lesser extent than complete substances; andfinally, if there is an infinite and independent substance, it is more of a thing than afinite and dependent substance. All this is completely self-evident.


In the ‘Argument Arranged in Geometrical Fashion’ at the end of the SecondReplies, Descartes makes the same points, though he makes no mention ofincomplete substances:

There are various degrees of reality, or being: a substance has more reality than anaccident or a mode; an infinite substance has more reality than a finite substance.Hence there is more objective reality in the idea of a substance than in the idea ofan accident; and there is more objective reality in the idea of an infinite substancethan in the idea of a finite substance.

(AT VII 165–6; CSM II 117)

Critics have objected that Descartes is operating with two distinct accounts ofthe dependence/independence distinction here. Kenny remarks that whereasthe dependence of finite substances on God is causal, the dependence of modeson substances is logical; modes inhere in substances as subjects, whereascreated substances are the effects of God as creator. Thus, Kenny claims,‘there is no uniform property of independence which things might possessin a greater or lesser degree’.10 It is, then, only by equivocating on the notion ofindependence that Descartes can treat God, finite substances, and modes aspoints on a common scale. But this is perhaps to see things in too Humean afashion. It is after all a commonplace that the so-called ‘Rationalists’ tended toassimilate causal to logical relations; as Bennett remarks à propos of Spinoza,‘it is not that he sees logical links as weaker than they are; rather, he sees causallinks as stronger’.11 Thus Descartes would probably have been unmoved bythe criticism that he is confusing two notions of independence; he would haveheld that there is just one property involved which is instantiated in varyingdegrees by God and finite substances. The assimilation of causal to logicalrelations is thus central to Descartes’ conception of degrees of reality. IfDescartes is guilty of a mistake here, it is a mistake of a deep kind; it is nomere surface muddle.

For our purposes, however, it is not essential to decide whether God andfinite substances share a single property of independence. As Loeb emphasizes,mind–body interaction takes place within the realm of creatures, and withinthis realm it is clearly logical independence that is at issue. What is important

10 Kenny, Descartes, p. 134.11 Jonathan Bennett, A Study of Spinoza’s Ethics (Cambridge: Cambridge University Press,

1984), p. 30.



is whether the independence criterion, as we may call it, is Descartes’ soleprinciple for determining degrees of reality among created beings. Loebassumes that it is, and this assumption plays a central role in his defence ofCartesian interactionism. For on this criterion the Causal Adequacy Principlewould be violated if and only if ‘modes of thinking substance cause materialsubstance itself (as distinct from its modes), and modes of material substancecause thinking substance itself (as distinct from its modes)’.12

In the Meditations Descartes does indeed write as if the independencecriterion is his sole yardstick. But elsewhere in his writings he seems to havea different criterion up his sleeve. Thus, in the Replies to the Second Objec-tions, Descartes writes:

Thus, when you talk of an ‘utterly perfect corporeal being’, and take the term‘utterly perfect’ in an absolute sense, so that a corporeal being is taken to be a beingin which all perfections are found, you are uttering a contradiction. The very natureof a body implies many imperfections, such as divisibility into parts, the fact thateach of its parts is different, and so on; for it is self-evident that it is a greaterperfection to be undivided than to be divided.

(AT VII 138; CSM II 99)13

Now, as Loeb recognizes, ‘perfection’ is a synonym for ‘reality’;14 in otherwords, Descartes is saying that minds are more real than bodies. Thus God ismore perfect, that is, more real than res extensa not just because he isindependent but also because he is a mind. So we cannot really accept Kenny’sremark that ‘Descartes’ scale of being is not the medieval hierarchy of God,angels, men, beasts, plants, matter. It has only three points: infinite substance,finite substance, and modes.’15 It seems that Descartes is more of a traditional-ist than Kenny allows, for the principle that mind is more perfect than bodygoes back at least to Augustine.Since Descartes has this further Augustinian criterion of reality, we can see

that Loeb’s defence of interaction is not adequate as it stands. We can also seewhy sense-perception rather than the initiation of bodily movements throughwilling is the real test case for the coherence of Cartesian interactionism. Theessence of the problem is easily stated. Sense-perception involves the action ofbody on mind; in other words, a mental event is produced by a physical cause.According to the Causal Adequacy Principle, there must be at least as muchreality in the cause as in the effect. Yet, on the Augustinian criterion of degrees

12 Loeb, From Descartes to Hume, pp. 140–1.13 There is, however, at least a hint of this second criterion in Meditation VI when Descartes

considers the possibility that his sensory ideas are caused by God or ‘some creature more noblethan body (aliqua creatura corpore nobilior)’ (AT VII 79; CSM II 55).

14 Loeb, From Descartes to Hume, p. 140.15 Kenny, Descartes, p. 134.



of reality, the mental is more real than the physical.16 Thus the danger is thaton Descartes’ theory of sense-perception, the effect, being mental, will have morereality than the cause—in direct violation of the Causal Adequacy Principle.

I I I

The problem of deciding whether Descartes’ account of sense-perceptionhonours the Causal Adequacy Principle is complicated by the fact that hedistinguishes two fundamental features of ideas. An idea, for Descartes,possesses both formal and objective reality. An idea has formal reality, inher-ently, as a state of mind or a mode of a thinking substance. An idea hasobjective reality by virtue of its representational content: its measure is theamount of formal reality which the object of the idea either possesses or wouldpossess if it existed. Thus, as Descartes explains in the Third Meditation, whileall ideas possess the same degree of formal reality, they differ in terms of theirdegree of objective reality (AT VII 40; CSM II 27–8). The idea of God, forinstance, possesses vastly more objective reality than the idea of a stone.

This dual character of ideas, formal and objective, makes the application ofthe Causal Adequacy Principle to ideas rather less than straightforward.Descartes’ actual way of applying the principle to ideas has come in for agreat deal of criticism.17 Yet it is not entirely clear just how Descartes doesthink the principle should be applied. His main statements on the issue aredominated by a single thesis about the objective reality of ideas:

In order for a given idea to contain such and such objective reality, it must surelyderive it from some cause which contains at least as much formal reality as thereis objective reality in the idea.

(AT VII 41; CSM II 28–9)

The objective reality of our ideas needs a cause which contains this reality notmerely objectively, but formally or eminently.


And when he proves the existence of the external world in the Sixth Medita-tion, Descartes sketches the same constraint on the causation of sensory ideas

16 Radner, ‘Is There a Problem?’, 44, makes reference to Augustine’s doctrine that the mind issuperior to the body.

17 Bernard Williams, in particular, has argued that Descartes has no right to say that the ideaof x needs as much reality in its cause as x itself would possess formally, for this implies thatexisting in idea is as real a way of existing as existing formally—something which Descartesdenies, and has reason to deny (Williams, Descartes, pp. 140–1). Cf. Margaret D. Wilson,Descartes (London: Routledge and Kegan Paul, 1978), pp. 137–8. Both Williams and Wilsonraise their objections during the course of criticizing Descartes’ first proof of the existence of Godin the Third Meditation.



in particular; he claims that the active faculty of producing the ideas of sensiblethings must exist in a substance which ‘contains either eminently or formallyall the reality which exists objectively in the ideas produced by this faculty’(AT VII 79; CSM II 55). It is difficult to know how much Descartes is claimingin such passages. His silence on the formal reality of ideas might lead oneto suppose that this is not something which he regards as needing a cause;perhaps he thinks that the objective reality is the only aspect of ideas whichneeds to be explained. Thus he may be giving a complete account of theimplications of the Causal Adequacy Principle for ideas. If so, we get thefollowing principle:

(1) The cause of the idea of x must contain as much reality formally oreminently as the idea of x possesses objectively.

On the other hand, Descartes may be doing something more limited. Herightly regards his thesis about the objective reality of ideas as a controversialone, and while insisting on this, he may feel himself able to take it for grantedthat the formal reality of ideas also requires a cause. If this is so, then acomplete statement of the applied principle would be the following:

(2) The cause of the idea of x must contain as much reality formally oreminently as the idea of x possesses both objectively and formally.

It is, I think, more natural to suppose that Descartes’ position is best capturedby (2).18 In other words, the Causal Adequacy Principle as it applies to ideas, isessentially double-barrelled. We shall begin by looking at the barrel which iscommon to (1) and (2). Let us call this the ‘objective reality requirement’.

At first sight the objective reality requirement is plain sailing for Descartes’theory of sense-perception. Suppose that I am seeing a table. Here I have asensory idea which has the table as its intentional object. Regarded formally, orin itself, the table is part of the cause of my idea; the table of course cannotconstitute the whole cause, for according to Descartes’ mechanistic picture,such things as light-particles and nerve-endings also play a role. In such a case,then, the objective reality requirement may seem to be straightforwardlyhonoured. There is as much formal reality in the cause as there is objectivelyin the effect, because my idea of the table is caused by the table itself and otherbodies.Unfortunately, however, the situation is not quite as straightforward as it

seems. One of the central themes of Descartes’ philosophy is that our sensoryideas, unlike our intellectual ones, are very confused; they are not a reliableguide to the nature of physical reality. Indeed, this mismatch between sense-perception and the world is perhaps the most basic of all the morals pointed by

18 This is the position taken by Williams, Descartes, p. 140.



the Meditations. Thus it may be argued that in their objective aspect, sensoryideas possess properties which are not possessed by their causes. The mostconspicuous among such properties are of course the secondary qualities. Myidea of the table, for example, represents it as having a brown top, whereas infact there is no categorical property of colour in the table itself.

This lack of correspondence between image and reality certainly compli-cates the issue, but it is not clear that it poses a real threat to the objectivereality requirement. Descartes might perhaps be in trouble if he adhered to theunqualified pre-existence principle. That principle is clearly violated if colourexists in my idea but not in the table itself or anything else in the physicalworld, for then there is something in the effect that does not pre-exist in thecause. But we have seen that Descartes does not in fact hold the pre-existenceprinciple in this unqualified form. On the contrary, what he applies to ideas isthe less restrictive principle that there must be at least as much reality in thecause as in the effect.

Some readers might agree that Descartes does not hold the pre-existenceprinciple in this unqualified form, and yet argue that the mismatch betweenideas and reality is still an embarrassment. It might be objected that the statusof secondary qualities for Descartes poses a threat to the Causal AdequacyPrinciple as embodied in the objective reality requirement. If such qualities ascolour have no being outside the mind, then there is a degree of reality in theeffect that is not present in the cause, for the object of the idea possessesfeatures that are purely mind-dependent. But, according to the Augustiniancriterion, the mental has more reality than the physical, and hence, onDescartes’ principles, cannot be caused by it.

Even in this more sophisticated form, such an objection is misguided. In thefirst place, it seems to involve a category mistake. If secondary qualities are inthe mind, then they are ideas, and like all ideas, must possess both formal andobjective reality. Considered in terms of their formal reality, however, ideas ofsecondary qualities are indeed merely modes of consciousness. Considered interms of their objective reality, or content, however, they are not mental at all;my sensory idea of brown, for example, is the idea of a property possessed by aphysical object. In this respect, secondary qualities would be on a par withmythical beings. A unicorn exists only in the mind, but my idea of a unicorn isnonetheless the idea of a physical creature. If secondary qualities are ideas,they are formally mental but objectively physical.

There is also a more straightforward way of replying to this objection. Theobjection assumes that, for Descartes, secondary qualities are purely mind-dependent, and this assumption is mistaken. In fact, Descartes seems to holdthat secondary qualities are genuine properties of bodies, though dispositionaland relational ones; he foreshadows the view developed by Locke, that they arepowers in bodies to produce ideas in us. In the Principles of PhilosophyDescartes comes very close to stating the Lockean thesis:



We have every reason to conclude that the properties in external objects to whichwe apply the terms light, smell, colour, smell, taste, sound, heat and cold—as wellas the other tactile qualities and even what are called substantial forms—are, sofar as we can see, simply various dispositions in those objects which make themable to set up various kinds of motions in our nerves which are required toproduce all the various sensations in our souls.

(AT VIIIA 322–3; CSM I 285)19

It is true, of course, that secondary qualities are not in bodies in the straight-forward categorical way that common sense takes them to be. The man in thestreet clearly does not suppose that colours, for example, are merely disposi-tional properties of objects. This is the truth of the claim that the manifestimage is not a reliable guide to the nature of physical reality. Moreover, forDescartes it is possible in principle to give a complete description of thephysical world in terms of primary qualities alone.20 But it does not followfrom this that secondary qualities are merely mind-dependent.When reality is measured by the Augustinian criterion, the objective reality

requirement is in no danger from sensory ideas. And the independence criter-ion would seem to leave it similarly unscathed. Although formally a mode, myidea of the table is objectively a substance; fortunately its cause is also asubstance, so cause and effect are on a par. If one wanted to be uncharitable,one could perhaps press an objection here. For it might be observed that inDescartes’ metaphysics there is, strictly speaking, only one res extensa—theentire physical universe. Thus what common sense takes to be substances are infact more or less arbitrarily selected fragments of a much larger whole. Bycontrast, whenwe consider the idea of the table from an objective viewpoint, wemust regard it as a substance; for we take the table to be a substance just assurely as we take it to be brown. Indeed, it might be said that consistencyrequires this, for we have earlier claimed that the revisionary nature of Des-cartes’ metaphysics leaves the objective reality of ideas unaffected.Such an objection does indeed seem uncharitable, and there are several

ways in which it could be met. In the first place, Descartes could reply that heis still prepared to recognize tables and chairs as substances; certainly in the

19 Since the original publication of this paper, Lawrence Nolan has argued that whenDescartes writes of secondary qualities here as ‘dispositions’ (dispositiones), he does not meandisposition in the modern sense; rather, he means the arrangement or texture of particles alongthe surface of a body; thus Descartes is not in fact anticipating the Lockean view of secondaryqualities as dispositions or powers to produce ideas in us. See L. Nolan, ‘Descartes on “What WeCall Color” ’, in L. Nolan (ed.), Primary and Secondary Qualities: The Historical and OngoingDebate (Oxford: Oxford University Press, 2011), p. 90. I am now largely persuaded by Nolan’sinterpretation. How far such a revised interpretation of Descartes’ position undercuts the claimthat he anticipates Locke’s view of secondary qualities is a matter of debate; even Locke at timesseems to identify secondary qualities with textures rather than powers or dispositionalproperties.

20 Cf. Williams, Descartes, p. 243.



Third Meditation he does not quarrel with the claim that a stone is a substance(AT VII 44; CSM II 30). But secondly, and more cogently, Descartes can drawon his scientific world picture; he can reply that the table is nothing like thetotal cause of a sensory idea, even in its objective aspect. On the contrary, it isone element in a mechanistic process which also involves, for example, themovement of light particles and the stimulation of nerve-endings. Descartesmight not wish to hold that every part of the physical universe is causallyinvolved in my seeing a table, but he could surely say that the physical processis so extensive that there is a sense in which res extensa is the cause.21 In otherwords, my seeing the table is caused by a substance. There is thus no violationof the objective reality requirement.

A more radical route to the same conclusion has been suggested by Marga-ret Wilson in another context. Drawing on the discussion of material falsity inthe Third Meditation, Wilson suggests that Descartes regards sensory ideas as‘mere nothings’ from the objective point of view.22 Clearly, if this is correct, itdisposes of the problem at a stroke. For if ideas of sense have no objectivereality, there can be no danger that the effect will have more reality than thecause. Wilson’s interpretation, however, seems to me textually unfounded;for one thing, it seems to depend on an illicit assimilation of sensory ideas ingeneral to materially false ideas. But Descartes surely holds that while allsensory ideas are confused, only those which are privative (like the idea ofcold) are materially false (AT VII 79; CSM II 55). In any case, Wilson’ssuggestion that, in terms of objective reality, sensations are ‘mere nothings’seems contradicted in the Sixth Meditation. After claiming that they cannot bethe cause of his sensory ideas, Descartes observes:

The only alternative is [that this active faculty of producing or bringing aboutideas] is a substance distinct from me—a substance which contains either for-mally or eminently all the reality which exists objectively in the ideas produced bythis faculty.


Surely it is presupposed here that sensory ideas do contain objective reality;they are not ‘mere nothings’. Thus Wilson’s interpretation must be rejected.Fortunately, it is not necessary for our purposes.

So far, then, we have shown that Descartes’ theory of sense-perceptionhonours the objective reality requirement:

21 Martial Gueroult claims that the objective reality of sensory ideas is caused by the modes ofbodies, but he does not argue for this claim. Gueroult, Descartes selon l’ordre des raisons, vol. 2(Paris: Aubier, 1968), p. 91.

22 Wilson, Descartes, p. 111. On p. 114 Wilson seems to qualify her original statement; sheclaims only that Descartes implies that ‘most ideas of sense may lack objective reality (includingextension, figure, motion, and situation, which are supposed to be ideas of intellect as well)’.(Emphasis added.) Cf. Gueroult, Descartes, vol. 1, p. 218.



(1) The cause of the idea of x must contain as much reality formally oreminently as the idea of x possesses objectively.

As we have seen, (2) includes a further requirement: the cause of the idea of xmust contain as much reality, formally or eminently, as the idea of x containsnot only objectively but formally. Does the additional requirement—let us callit ‘the formal reality requirement’—sabotage any defence of Descartes’ theoryof sense-perception?When wemove to the formal reality requirement, we touch upon traditional

worries about Cartesian interaction. We can no longer avoid the ontologicaldivide that separates ideas from physical objects. In its formal aspect, an idea isa mode of a thinking substance, but on the interactionist model its cause ispurely physical. On the Augustinianmeasure of degrees of reality, the mental ismore perfect, and hence more real, than the physical. So it would seem thatDescartes cannot satisfy the formal reality requirement unless he abandons theAugustinian criterion. Something, it would seem, has got to give.Something has got to give, but less than one might think. Descartes need not

give up the Augustinian criterion altogether; all he needs to do is subordinateit to the independence criterion. Descartes can say that the Augustiniancriterion is a subsidiary principle of ordering within the categories of sub-stance and mode. In other words, within the category of substance, a mind ismore real than a body; similarly, within the category of modes, an idea is morereal than, for example, the shape of a physical object (taking this to be a modeof an extended substance). Thus any substance qua substance ranks higherthan any mode, even a mode of thought. If Descartes adopts this option, thenthe threat of inconsistency disappears. For when I am seeing a table, a mode ofthought is being caused by res extensa. Since even an extended substance ismore real than a mode of thought, there is no violation of the formal realityrequirement.It is, I believe, reasonable to assume that the independence criterion takes

precedence in Descartes’ system. For in theMeditations it is the independencecriterion which Descartes wishes to parade, and this is surely evidence of hissense of priorities. Indeed, the Augustinian criterion finds explicit expressiononly in the Replies to Objections. It might be inferred from this that theAugustinian criterion is more a polemical, ad hominem tool than an essentialingredient in Descartes’ system. But even if this is disputed, and the proposedordering seems ad hoc, there is still a way in which Descartes can effectivelycounter the accusation of inconsistency. The coherence of Cartesian inter-actionism can be defended even if Descartes is committed to holding thatnothing mental, in its formal aspect, can be caused by a physical substance.We have seen earlier that when Descartes discusses the causation of sense-

ideas, he focuses all his attention on their objective reality. Now we need nottake this as implying that only the objective reality of ideas stands in need of a



cause; since in its formal aspect, an idea is something real, it seems unlikelythat Descartes would say this. But Descartes’ approach to the topic doesprompt one to wonder whether the formal and objective aspects of ideasmust have the same cause; perhaps Descartes’ view is that while in theirobjective aspects, sensory ideas are caused by bodies, as modes of a thinkingsubstance they are caused by something else.

Support for the suggestion that the formal and objective aspects of ideas areseparately caused comes from one of Descartes’ key metaphors. Perhapssurprisingly in view of his commitment to innate ideas, Descartes is preparedto compare the mind to wax which can take on various shapes. In a letter toMesland Descartes is very explicit on this point:

I regard the difference between the soul and its ideas as the same as that between apiece of wax and the various shapes it can take. Just as it is not an activity butpassivity in the wax, to take on various shapes, so, it seems to me, it is a passivityin the soul to receive one or other idea, and only its volitions are activities.

(2 May 1644 (?), AT IV 113; CSMK III 232)

If we continue with this metaphor, we get a certain picture of the role ofphysical objects in sense-perception. Bodies are causally responsible for theobjective reality of our ideas: they determine, as it were, the nature of theshapes the wax embodies. But though they cause the mind to be modified in aparticular way, they do not bring it about that there is something mental to bemodified. In terms of Descartes’ own metaphor, the seal or whatever it is thatcauses the shapes does not explain the presence or persistence of the wax. Inother words, bodies are causally responsible for the objective, but not theformal, reality of ideas.

Descartes’ wax metaphor, then, strongly suggests that there is a division oflabour in the causation of sensory ideas. If the role of bodies is limited in thisway, what is it that accounts for the formal reality of ideas? For the purposes ofdefending interactionism, it is not strictly necessary to answer this question; itwould be enough to establish that there is a division of labour, and that the roleof bodies extends only to the objective reality of our sense ideas. But we can,I think, suggest a possible answer. Recall that in the Third Meditation Des-cartes proposes his continuous creation doctrine. According to this doctrine,finite substances have no inherent tendency to persist in existence; on thecontrary, they depend causally at every moment on the power of God whoconserves the universe by continuously re-creating it (AT VII 49; CSM II 33).Thus, for Descartes, God not only creates minds in the first place, he is also atleast a causally necessary condition of their continued existence. So if Des-cartes wishes to explain why there is something mental, capable of receivingdeterminate modifications, it seems he must appeal to God. If this is the case,then the formal reality requirement is honoured as handsomely as possible, forGod has infinite formal reality.



IV

So far we have focused exclusively on the causality of sense-perceptions. But ofcourse not all the mental events which are caused by bodies are of this type.Indeed, when one considers the action of body on mind, what one may thinkof first is not sense-perception but such things as pain and hunger sensations.The pain caused by the dentist’s drill is certainly a more striking case of body–mind interaction than my visual experiences caused by the table in front ofme. Thus, a defence of the coherence of Cartesian interactionism requires atleast some account of sensations.Not surprisingly, then, sensations tend to be prominent in discussions of

Cartesian dualism. Curiously, however, Descartes’ treatment of the status ofsuch sensations is rather obscure. It is clear, of course, that sense-perceptionsare like sensations in that they are both confused modes of thinking that arisefrom the union of mind and body; indeed, there is much in Descartes’philosophy that drives him to assimilate sense-perceptions and sensations.What is not clear is how far and in what way Descartes wishes to draw adistinction between the two. Unlike sense-perceptions, sensations are not,strictly speaking, ideas. All ideas, for Descartes, are thoughts or modes ofconsciousness, but not all thoughts or modes of consciousness are ideas in thestrict sense: ‘Some of my thoughts (cogitationes) are as it were the images ofthings (tanquam rerum imagines), and it is only in these cases that the term“idea” is strictly appropriate; for example, when I think of a man, or a chimera,or the sky, or an angel, or God’ (AT VII 37; CSM II 25). The problem is todecide just what Descartes is committed to by his denial that all cogitationesare ideas in the strict sense. In particular, does he mean to deny that pains haveobjective reality? If this were Descartes’ view, then we should have to give upour earlier suggestion that bodies play no causal role in the case of formalreality, for sensations are said to arise from the mind’s union with the body(AT VII 81; CSM II 56). But it is difficult to see how Descartes couldconsistently hold that there are cogitationes without content. Fortunately,there is no need to suppose that Descartes denies that pains have objectivereality. What he seems to deny is that all cogitationes are, ‘as it were, pictures ofthings (tanquam rerum imagines)’; only those which meet this standard are,strictly speaking, ideas. Most writers concentrate on the first part of thisrequirement: ideas are in some sense like pictures. But the second part ofthe requirement is also significant: what Descartes seems to be saying here isthat, strictly speaking, only those thoughts are ideas which have thing-likeobjects, and this interpretation is confirmed by Descartes’ list of examples.Such a claim in no way implies that only ideas have objective reality: it leavesopen the possibility that other cogitationes may have objects or representa-tional content of a different kind.



If this is correct, then we can see how Descartes would apply the CausalAdequacy Principle to sensations. Sensations by their nature have objects, butthese objects are not thing-like; rather, they are more like properties ormodifications. A pain, then, will be a ‘thought’ which typically represents amodification in a certain part of the body. As we have seen earlier, Descarteswill of course criticize the view that there is really anything in my foot similarto my pain, but as we have also seen, this does not affect the objective reality ofthe sensation. Since pains are not, objectively speaking, thing-like or substan-tial, we can see that they are easily covered by the objective reality require-ment. In its objective aspect, the pain is a mode, but its cause is a substance,namely res extensa. And in its formal aspect, it is covered by our earlierdiscussion of sense-perception.

V

We have seen that, as applied to ideas, the Causal Adequacy Principle consistsof two requirements. I have sought to show that Descartes is in no danger ofviolating either. The most that has been conceded is that, to meet the secondrequirement, he might be tempted to weaken his interactionist thesis: he mightchoose to say that the formal reality of ideas is not caused by bodies, but byGod. Even this is not a position that is forced upon Descartes, for he has theoption of playing down his Augustinian criterion. But if Descartes does chooseto resort to God, his theory is still in an important sense interactionist, forbodies are causally responsible for the objective reality of ideas. There is nodanger that Descartes’ thesis will simply collapse into occasionalism.

In this essay I have sought to defend the internal coherence of Cartesianinteractionism. I have not, of course, tried to defend the Causal AdequacyPrinciple itself, or even Descartes’ way of applying it to ideas. My concern withthe internal coherence of Descartes’ position also explains the exclusive focuson the one direction of interaction. On Cartesian principles there can be noproblem posed by the causation of physical changes by willing, for here theAugustinian principle works to Descartes’ advantage. Modern philosophersmay find Descartes’ account of voluntary movements mysterious, but they doso for reasons that are quite external to his system.



3

Intellect and Illumination in Malebranche

One of the hallmarks of Descartes’ philosophy is his doctrine that the mindhas a faculty of pure intellect. In the Sixth Meditation, for example, Descartestells us that it is by means of this faculty that the mind is capable of graspingcomplex geometrical ideas such as that of the chiliagon (AT VII 72–3; CSM II50–1). Indeed, Descartes sometimes writes as if the faculty of pure intellectalone is essential to the mind; the faculties of sensation and imagination, bycontrast, are contingent powers of the mind which arise from its union andintermixture with the body.1 Descartes’ commitment to the doctrine of pureintellect is so striking that it has sometimes been taken to be a definingcharacteristic not merely of the Cartesian but of the whole rationalist tradition.Certainly it is difficult to imagine that any self-professed disciple of Descarteswould abandon the doctrine. Yet precisely this is what happened in the case ofDescartes’ most famous disciple, Malebranche.Malebranche’s teaching in this area has been poorly understood in the Eng-

lish-speakingworld. One reason for this is that he is known almost exclusively onthe basis of The Search After Truth. But despite subsequent revisions, this work isnot the best guide to Malebranche’s mature thought; in the SearchMalebrancheis still seeking to establish his own independent philosophical identity. In thisessay I shall argue that, under Augustinian influence, Malebranche came toabandon the Cartesian doctrine of pure intellect in favour of a version of divineillumination theory which has no room for it. I shall argue that the disappearanceof the Cartesian doctrine left a void in his philosophy which he sought to fill withthe puzzling theory of efficacious ideas. I shall also argue that, though themotivation for its introduction is clear, the doctrine of causally efficacious ideasis subject to at least one serious difficulty which Malebranche does little toresolve. I shall end by suggesting that in his later philosophy of mind Male-branche has more in common with Berkeley than with Cartesian rationalism.2

1 On this issue see M.D. Wilson, Descartes (London: Routledge and Kegan Paul, 1978),pp. 200–1.

2 At this point a caveat should be entered. Although I believe it is possible to speak ofMalebranche’s development, the issue is complicated by the fact that he did not simply embody


I

There is no doubt that in his first work, The Search After Truth, Malebrancheembraces a Cartesian doctrine of pure intellect. Malebranche’s picture of themind in this work is somewhat complex, but its essential features are familiarto us from Descartes. The mind is a substance whose essence is thought (SAT3.1.1, OCM I 381; LO 198); it has two principal faculties, will and understand-ing (SAT 1.1, OCM I 40–1; LO 2). The understanding is defined as ‘the passivefaculty of the soul by means of which it receives all the different modificationsof which it is capable’ (SAT 1.1, OCM I 43; LO 3). The term ‘understanding’ or‘intellect’ is to be taken in a broad sense here, for Malebranche tells us that itis through this faculty that the mind both senses and imagines; the sensesand the imagination ‘are nothing but the understanding perceiving objectsthrough the organs of the body’ (SAT 1.1, OCM I 43; LO 3). Later in the workMalebranche speaks of the ‘pure understanding’ which is defined as ‘themind’s faculty of knowing external objects without forming corporeal imagesof them in the brain to represent them’ (SAT 3.1.1, OCM I 381; LO 198). It isby means of this faculty that the mind is aware of intellectual ideas such as theconcepts of geometry. Such ideas are not merely objects of abstract thought;they are also involved in our perception of the physical world.3

Even at this stage of his career, however, Malebranche is not a strictCartesian; he seeks to find room for at least a version of the Augustiniandoctrine of divine illumination. Drawing ultimately on the prologue to StJohn’s gospel, Malebranche echoes Augustine by insisting that the mind is nota light to itself (Preface, SAT, OCM I 24; LO xxviii).4 At this point, however,the doctrine of divine illumination is simply a thesis about the objects ofhuman thought and knowledge. The objects of the pure understanding are ofcourse ideas, but ideas are not mind-dependent entities as they are forDescartes; rather, they are to be construed in a Platonic way as abstract logicalentities whose locus is God. From this standpoint Malebranche can reject,implicitly or explicitly, certain characteristic Cartesian claims about ideas.Since ideas are abstract entities whose locus is God, the intellect cannotproduce ideas; hence, there can be no factitious ideas. Nor can the intellectdiscover ideas in itself; hence, there can be no innate ideas in this sense (SAT

his changes of mind in new works; he also revised his earlier works to reflect the development ofhis thinking. Sometimes Malebranche allowed earlier statements to stand in later editions whichseem inconsistent with his more mature views. Thus a work such as The Search After Truth (firstedition 1674–5; final edition 1712) is, in its final form, to some extent a palimpsest.

3 At SAT 3.1.1 Malebranche writes of ‘intellectual ideas, by means of which the understandingis aware of external objects’ (OCM I 381; LO 198. Cf. SAT 3.2.6, OCM I 445; LO 234.).

4 Here Malebranche quotes Augustine: ‘Noli putare te ipsam esse lucem’. At SAT 3.2.6Malebranche quotes the prologue to St John’s gospel (I.9): ‘He is the true light that illuminateseveryone who comes into the world’ (OCM I 440; LO 231).



3.2.4, OCM I 429–30; LO 226–7). Indeed, the Cartesian doctrine of divinelyimplanted innate ideas can be convicted of something like a category mistake,for ideas are not mental entities of any sort. Thus Malebranche parts companywith Descartes’ psychological conception of ideas, but at this stage he iscommitted to a theory of divine illumination which still leaves room for aCartesian doctrine of pure intellect, for it is by means of this faculty that thehuman mind is related to abstract objects: ideas in God.In his mature works, such as the Dialogues on Metaphysics, however,

Malebranche espouses a stronger version of the doctrine of divine illumination.It ceases to be a thesis simply about the objects of thought and knowledge; itnow has radical implications for the intrinsic properties of the mind. TheAugustinian claim that the mind is not a light to itself is now taken to imply athoroughly bleak picture of the mind’s native resources. Considered in abstrac-tion from divine illumination, the mind has no cognitive machinery of its own;the only properties it possesses are obscure and confused sensations (senti-ments) which are without representational content and of no cognitive value.Here are some representative passages:

Created reason, our soul, the human mind, the purest and most sublime intel-lects, can indeed see the light; but they cannot produce it or draw it from theirown resources; they cannot engender it from their substance. They can discovereternal, immutable, necessary truths in the divine Word, in eternal, immutable,necessary Wisdom; but in themselves they only find sensations often quite lively,yet always obscure and confused, modalities full of darkness.

(DMR III.4, OCM XII 64–5; JS 32–3)

I am not a light to myself, because my substance and my modalities are onlydarkness.

(DMR III.7, OCM XII 67; JS 35)

I cannot reiterate this to you too often: we must not consult our senses and theirrespective modalities, which are sheer darkness, but Reason which enlightens usby its divine Ideas, by ideas that are immutable, necessary, eternal.

(DMR III.15, OCM XII 82; JS 47)

Although the substance of the soul is not intelligible to the soul itself and itsmodalities cannot enlighten it, these same modalities, when they are joined to theintelligible extension which is the archetype of bodies and they make thisextension sensible, can show us its relations in which the truths of geometryand physics consist. But still it is true to say that the soul is not its own light toitself, that its modalities are only darkness, and that it discovers exact truths onlyin ideas contained in Reason.

(DMR V.5, OCM XII 116; JS 77)

The mind, then, can achieve knowledge of a priori truths and can perceivethe objective geometrical properties of bodies only by being illuminated byGod’s ideas. But to say that the mind is capable of receiving such divineillumination is not, it seems, to say that it naturally possesses a faculty of


Intellect and Illumination in Malebranche 45

pure intellect by virtue of which it can be related to these ideas; the mind’sintrinsic state is simply one of darkness. As the first quotation shows,Malebranche is still capable of describing the mind as an intellect, but it isclear that he is not thinking of a faculty that it possesses independently ofdivine illumination; in patristic terminology, the mind is a lumen illumina-tum (illuminated light), not a lumen illuminans (illuminating light) (SAT,Elucidation X, OCM III 157–8; LO 630).5 Significantly, Malebranche writesthat it is the mind’s modalities—not a faculty of intellect—which are joinedto intelligible extension in God, and these modalities are variously describedas obscure and confused. It is of course natural to object that, in the absenceof a doctrine of pure intellect, Malebranche’s talk of divine illuminationoffers us less a philosophical theory than a striking metaphor. We shall see,however, in the next section that Malebranche provides a way of unpackingthe metaphor.

In one way Malebranche’s picture of the mind’s native state is evenbleaker than so far suggested. I have said that, for Malebranche, the onlyintrinsic properties of the mind are sentiments, obscure and confused mo-dalities; as Malebranche says, ‘in themselves [minds] find only sensa-tions . . .modalities full of darkness’ (DMR III.4, OCM XII 65; JS 33). Suchsentiments are intrinsic properties of the mind at least in the sense that theyare non-relational; to have a sentiment, such as a sensation of red, is simplyto be in a certain adverbial state. Even sentiments, however, arise only fromthe mind’s union with the body; they have occasional causes which arephysical events in the brain. Thus if intrinsic properties are contrasted, notwith relational but with interactive properties, then even sentiments are notintrinsic properties of the mind in this sense. It seems, then, that if weconsider the Malebranchian mind of the Dialogues in abstraction from itsunions with God and its body, it has no actual properties of any sort; it is forthis reason that Alquié can describe the Malebranchian mind as a purepotentiality (virtualité). It is important to note, however, that Malebranchewould resist the implication that the mind has no essential properties. Oneof the constants of Malebranche’s philosophy seems to be the claim that it isessential to the human mind to be united with God; according to The SearchAfter Truth, the relation that minds have to God is ‘natural, necessary, andabsolutely indispensable’ (SAT, Preface, OCM I 10; LO xx), and there is noevidence that Malebranche abandoned this claim. The thesis does not ofcourse imply that the perception of any given idea is essential to the mind;there might be minds which had no perception of the idea of a rhombus.Even more clearly it does not imply that any given perception of an idea isessential to the mind. But it does mean that there could not be a mind which

5 Malebranche cites the Church Fathers, St Cyril of Alexandria, St Augustine, and St Gregoryfor this distinction.



had no perception of any of the ideas in God; there could not be a mindwhich had no access to geometrical concepts at all. Thus the perception ofideas in God is thoroughly relational, but it is nonetheless essential to mindto have some such perception.Why did Malebranche come to abandon the Cartesian doctrine of pure

intellect in favour of the thesis that the mind is intrinsically devoid of allproperties except sentiments? As so often with Malebranche, a combinationof factors was probably at work. In part, the motivation appears to havebeen theological; he seems to have come to feel that sound theology requireda stricter interpretation of the Augustinian, and ultimately Johannine, doc-trine that the mind is not a light to itself. In the Dialogues on Metaphysics,for instance, Aristes remarks that the idea of being a light to himself inspireshim with a certain kind of horror (DMR V.4, OCM XII 115; JS 76); thevehemence of the language here suggests a concern on Malebranche’s partto push the doctrine of the mind’s lack of cognitive self-sufficiency toextreme lengths. Not merely must the mind be denied the possibility offinding the objects of thought and knowledge within itself; it must also bedenied the possession of all natural faculties for the acquisition of know-ledge. To leave the mind in possession of such faculties would be to implythat it was still in some degree a source of light, and this would be contraryto the patristic doctrine that the human mind is a lumen illuminatum, not alumen illuminans.But it is also plausible to suppose that Malebranche had more purely

philosophical reasons for rejecting the doctrine of pure intellect. Malebranchemay have been motivated by his deep anti-Scholastic distrust of the wholelanguage of faculties. In Elucidation X of The Search After TruthMalebrancheconsiders an imaginary Cartesian objection to the doctrine that ‘only Godenlightens us and that we see all things in him’ (OCM III 144; LO 622). TheCartesian is made to object that a simpler explanation is at hand: ‘our soulthinks because of its nature. In creating it, God gave it the faculty of thinkingand it needs nothing more’ (OCM III 144; LO 622). In reply Malebranchetakes the Cartesians to task for their inconsistency with regard to facultyexplanations:

I am amazed that the Cartesian gentlemen who so rightly reject the general termsnature and faculty should so willingly employ them on this occasion. They criticizethose who say that fire burns by its nature or that it changes certain bodies intoglass by a natural faculty, and yet some of them do not hesitate to say that thehuman mind produces in itself the ideas of all things by its nature, because it hasthe faculty of thinking. But, with all due respect, these terms are no moremeaningful in their mouth than in the mouth of the Peripatetics. . . . Just as it isfalse that matter, although capable of figure and motion, has in itself a power, afaculty, a nature, by which it canmove itself or give itself a figure that is now round,now square, so it is false that the soul, although naturally and essentially capable of



knowledge and volition, has any faculty by which it can produce in itself its ownideas or its own impulse toward the good.

(OCM III 144–5; LO 622)6

The general thrust of the passage is clear, but what exactly is the specific targetof Malebranche’s attack? Consider the following four claims:

(1) The mind has a faculty of thinking whereby it can produce in itself ideas.(2) The mind has a faculty of thinking whereby it can attend to (or activate)

innate ideas implanted by God.(3) The mind has a faculty of thinking whereby it can receive into itself

ideas from an external source.(4) The mind has a faculty of thinking whereby it can perceive ideas in God.

Now what is most prominent in this passage from Elucidation X is Male-branche’s opposition to (1) (ideas here are presumably to be taken as occur-rent thoughts). Yet, as we have already seen, even in The Search After TruthMalebranche rejects not merely (1), but (2) and (3) as well. On my interpret-ation, in the Dialogues on Metaphysics he also rejects (4); it is this further stepwhich constitutes the difference between the positions of the two works. Itmay seem, then, that Malebranche’s anti-Cartesian broadside in the Elucida-tion X is powerless to explain the difference between the early, more CartesianSearch After Truth and the later Dialogues on Metaphysics, for it appears tocontain nothing which Malebranche had not earlier asserted in the main bodyof the work. This is a forceful objection, yet in response it can be said thatalthough it is the rejection of (1) which is most striking in this passage, there isalso the suggestion of a stronger claim: all propositions which ascribe facultiesto the mind are strictly false. Malebranche even says that terms such as ‘nature’and ‘faculty’ are actually meaningless; his view seems to be that while theseterms have no meaning, the propositions into which they enter are to beregarded as false. If Malebranche does intend the stronger claim, then he iscommitted to the rejection not just of (1) through (3) but of (4) as well; for ifno propositions ascribing faculties to the mind are true, then a fortiori nopropositions which ascribe a faculty of pure intellect to the mind are true. Itseems possible that Malebranche may have been guilty of a slide in his thoughton this topic; he may have begun with the anti-Scholastic thesis that sincefaculty explanations are circular, no occurrent thought can be explained inthese terms, and then moved insensibly to the more radical thesis that allpropositions ascribing faculties to minds are false.

6 It is true that Malebranche writes of the faculty of thinking, rather than the faculty of pureintellect. But it is also worth noting that he denies that the mind ‘has any faculties by which it canproduce in itself its own ideas’. Thus the faculty of the doctrine of pure intellect is comprehendedin Malebranche’s attack here.



Malebranche’s rejection in his later works of the faculty of pure intellect isradically anti-Cartesian, but it is worth remarking that even his later positionretains one link with Descartes. Recall that, at least when contrasting it withthe will, Descartes insists on the passivity of the intellect; he tells Regius, forinstance, that ‘strictly, understanding is the passivity of the mind and willingits activity’ (May 1641, AT III 372; CSMK III 182). In his early philosophyMalebranche took over from Descartes the doctrine of the passivity of theintellect, both in the broad and narrow senses of the term which we distin-guished earlier. In his later philosophy he rejected all talk of mental facultiessuch as intellect and will, but he remained a Cartesian at least to the extent offinding room for a theory of mental passivity; but what was passive was notsimply a faculty of the mind, as Descartes taught, but the mind itself in all itsstates.

I I

The disappearance of the Cartesian doctrine of pure intellect leaves a void inMalebranche’s philosophy. The mind, we are assured, is not a light to itself; itis a lumen illuminatum, not a lumen illuminans. But these are simply nicemetaphors until they are unpacked in terms of philosophical theory. If themind has no faculty of intellectual intuition, then it is natural to ask how it canever apprehend the ideas in God which are supposed to illuminate it. It is tosolve this problem, I suggest, that Malebranche introduces the doctrine ofefficacious ideas—a doctrine which, as Robinet has argued, does not seriouslyappear until late in his career.7 In other words, Malebranche saw the need tounpack the metaphor of divine illumination, and he came to believe that thiscould only be done in causal terms. Once the theory of pure intellect had beenrejected, the only possible account of how the mind makes contact with divineideas was one which holds that they act directly on the mind; they therebycause cognitive states to arise in a substance which is devoid of all cognitivecapacities of its own. Thus, one of the most distinctive features of Male-branche’s later theory of ideas is that the intentional relation between themind and its objects is now construed as a causal relation; to say that a mentalstate intends an idea is to say that the mental state is the effect of the idea. In a

7 A. Robinet, Système et existence dans l’oeuvre de Malebranche (Paris: Vrin, 1965), pp. 259–62.According to Robinet, ‘à partir de 1695 l’idée, qui est infinie, éternelle, immuable, nécessaire,etc . . . reçoit en un sens précis le qualificatif d’ “efficace” qui n’apparaissait jusqu’ici que rarementau hasard de la plume’ (p. 259). Alquié, in Le Cartésianisme de Malebranche (Paris: Vrin, 1974),accepts Robinet’s thesis with some reservations; he points out that the efficacy of ideas is affirmedin a text from 1684 (p. 210, note 8). Certainly the theory of efficacious ideas is already present insubstance in the first edition of the Dialogues on Metaphysics, which dates from 1688.



letter to de Mairan, Malebranche remarks that created extension ‘cannot bethe immediate object of the mind because it cannot affect the mind, act on it’(12 June 1714, OCM XIX 882). Thus, acting on the mind is a necessarycondition for being its immediate object; indeed, it seems that it is also asufficient condition. In other words, x is the immediate object of the mind ifand only if x acts on the mind.

Various commentators have emphasized the novelty in Malebranche’sthought of the thesis that ideas act on, affect, touch, or modify the mind.But it is not always precisely clear what is at issue here. Some scholars, such asRobinet, seem to want to do more than draw our attention to the new causalconstrual of the intentional relation; they seem to suggest that it is only withthe introduction of causally efficacious ideas that Malebranche comes to viewthe mind as having any modifications in perceiving ideas.8 It is certainly truethat in his earlier works such as The Search After Truth Malebranche tends tobe silent or at least vague about what, if anything, goes on in the mind whenit perceives an idea in God.9 He could hardly deny, however, that the state ofa mind perceiving the idea of a circle differs from the state of a mindperceiving the idea of a triangle. What is less clear is whether, for Malebranche,the difference between these two states could be specified in non-relationalterms. Indeed, it is quite possible that, for the earlier Malebranche, this couldnot be done. For perception, in his eyes, is essentially relational, and there is noevidence that he believed that perception itself was founded on further intrin-sic facts about the mind. If this was his position, then we can perhaps clarifythe change in his thought brought about by the introduction of the doctrine ofefficacious ideas. Perception is still a relation between a mind and its idea, butit is now a causal relation, and this changes things considerably; on any normalunderstanding of causal relations, it surely implies that when ideas act on thehuman mind they produce a change in its intrinsic (i.e. non-relational) states.Certainly this is the way we think about what we (if not Malebranche) wouldregard as cases of physical causality; for example, when a lighted match isthrown into a tank of petrol, we do not think it is possible to give only arelational description of the effect of this action. If modifications are under-stood to be non-relational properties, then in this sense, and this sense alone, itcould be said that it is only with the introduction of efficacious ideas thatMalebranche comes to see the perception of ideas in God as implying theexistence of mental modifications.

8 Robinet, Système et existence, p. 231.9 At SAT 3.2.6, for example, Malebranche writes that ‘when we perceive something sensible

two things are found in our perception: sensation and pure idea’ (OCM I 445; LO 234), but hedoes not explain what mental modification, if any, corresponds to the idea. It must be remem-bered that, unlike sentiments, ideas for Malebranche are not mental entities.



As so far presented, the doctrine of efficacious ideas has a fairly modestscope. As I have argued above, the doctrine seems to be introduced to fill a gapin Malebranche’s philosophy; it explains what was formerly explained in termsof the Cartesian theory of the faculty of pure intellect. In other words, thedoctrine provides a new theory of abstract thought and of that element even insense-perception which involves the mind’s relations to ideas; for Male-branche, it is through access to God’s ideas that we perceive the objective,geometrical properties of bodies. On its introduction, then, the doctrine hasno implications whatever for the realm of sentiments (secondary qualitiesand bodily sensations such as pain and pleasure). Thus, Malebranche canstill make the familiar contrast between the realms of ideas and sensations: themind has sensations by virtue of the laws of its union with the body, but itperceives ideas by virtue of its union with God. Now, however, the unionbetween the human mind and God is to be understood in terms of the actionof his efficacious ideas.It would be natural to expect that in his later philosophyMalebranche would

wish to retain the familiar contrast between the spheres of ideas and sensations;certainly there is nothing in the theory of efficacious ideas itself which requireshim to obliterate it. Curiously, however, in his later philosophy Malebranchedoes not do what we might expect, for he extends the doctrine of efficaciousideas to the realm of sensations.10 The position which he comes to hold is thatall of the mind’s states are the effects of God’s efficacious ideas. Differences inmental states—for example, between conceiving a circle and sensibly perceiv-ing a circular figure—are explained in terms of the different ways in which oneand the same idea in God affects our minds. In the Dialogues on Metaphysics,for example, Theodore says that there is ‘one and only one idea of a hand . . . anidea which affects in different ways, which acts on our souls andwhichmodifiesthe soul with colour, heat, pain etc.’ (DMRV.5, OCMXII 116; JS 77).11 In a laterevision to the Christian Conversations Malebranche writes of the idea ofextension rather than the idea of a particular physical object, but otherwisehe offers a similar explanation:

When the idea of extension affects or modifies the mind with a pure perception,then the mind simply conceives this extension. But when the idea of extensiontouches the mind in a livelier fashion, and affects it with a sensible perception,

10 Robinet significantly entitles a section of his work: ‘Extension de la vision en Dieu audomaine de sentiment’ (Système et existence, p. 273).

11 The phrase ‘idea of a hand’ is found only in the fourth and final edition of 1711. There is nodoubt, however, that even the extended form of the theory of efficacious ideas is present in thefirst edition of the Dialogues (1688) Malebranche writes, for instance: ‘C’est donc l’idée oul’archetype des corps qui nous affecte diversement. Je veux dire, que c’est la substance intelligiblede la Raison qui agit dans notre esprit par son efficace toute-puissante, & qui le touche et lemodifie de couleur, de saveur, de douleur, par ce qu’il y a en elle ce qui represente le corps’(Système et existence, p. 273).



then the mind sees or senses extension. The mind sees it [i.e. extension] when thisperception is a sensation of colour; and it senses or perceives it in a still morelively fashion when the perception with which intelligible extension modifies it isa pain. For colour, pain, and all the other sensations are only sensible perceptionsproduced in intelligences by intelligible ideas.

(OCM IV 75–6)

Although Malebranche is not explicit on this point, presumably he intends tooffer here a philosophical analysis of the distinction between conceiving andsensibly perceiving; the difference between these two kinds of mental states isactually constituted by the more or less lively way in which God’s ideas act onthe human mind.

Malebranche’s extension of the doctrine of efficacious ideas to the realm ofsensations sometimes generates a certain incoherence in his model of mind.The appearance of incoherence is perhaps especially striking in the Dialogueson Metaphysics. The dominant emphasis of the Dialogues falls on the contrastbetween the obscurity of the mind’s own modalities, sensations, and the lightof those perceptions which it has by virtue of the action of ideas in God. Such aposition hardly seems to square with the thesis that all mental states, includingsensations, are the result of efficacious ideas. The basic, narrow doctrine ofefficacious ideas exists simply side by side with the extended version. Here, ason other occasions in his writings, Malebranche was not too careful aboutremoving inconsistencies which result from apparent developments in histhinking.

I I I

The basic motivation for the introduction of the theory of efficacious ideas isclear: Malebranche needs a philosophical substitute for the Cartesian theory ofpure intellect if he is to explain how the mind makes contact with divine ideas.Otherwise the doctrine of divine illumination will simply be an uncashedmetaphor. But Malebranche pays a high price for jettisoning the Cartesiantheory, for the doctrine of efficacious ideas involves at least one seriousproblem. I now consider several difficulties in the doctrine; two of these affectthe basic doctrine, and a third affects only its extended form.

At least one commentator has questioned whether, even in his later phil-osophy, Malebranche really believed in the causal efficacy of ideas them-selves.12 Alquié finds an ambiguity in Malebranche’s thought on this issue;in his view, Malebranche tends to conflate the claim that ideas themselves are

12 Alquié, Le Cartésianisme de Malebranche, pp. 210–11.



efficacious and the claim that it is God alone who acts on the human mind bymeans of ideas. According to Alquié, in one case causal efficacy is attributedto ideas alone; in the other case, it is attributed to God’s will, and not to hisideas.Alquié seems to think that each thesis is separately intelligible, and that

Malebranche’s mistake lies simply in muddling the two claims. But this,I think, does not go to the root of the problem. Now it is true that Malebranchesometimes says that ideas themselves are efficacious and at other times thatGod alone acts by means of ideas.13 But one cannot simply assume that thesetwo claims are inconsistent; indeed, it seems that they are not. In the firstplace, Malebranche’s thesis that God alone acts on our minds by means ofideas need not be taken as implying that ideas themselves are not causallyactive; surely his point is rather that no substance other than God—neitherangels nor bodies, for example—can act on human minds. Secondly, andrelatedly, we may note that normally when we say that A acts by means ofB, we do not intend to deny the attribution of causal powers to B. For example,when I use a bat to hit a ball (i.e., when I hit the ball by means of a bat), wewould not deny that the bat plays a causal role. Or again, when the murdererin the thriller kills his victim by means of arsenic, the arsenic is obviouslyregarded as a causal agent. Of course, even if we set on one side possiblecomplications posed by occasionalism, it can still be pointed out that there isan important disanalogy between these cases and efficacious ideas; bats andarsenic are instruments external to the person who uses them, whereas ideasare not external to God. But this analogy actually weakens the force of Alquié’sobjection. For if God acts on our minds by means of ideas he acts by means ofwhat is ‘in him’; once this is recognized, we can see that Malebranche comesvery close at least to saying that God acts on our minds qua locus of ideas.Thus the two claims which Malebranche is alleged to muddle are eitheractually equivalent, or very nearly so. That they are indeed equivalent issuggested by Malebranche’s remark that ‘ideas are only the efficacious sub-stance of the divinity’ (Conversations chrétiennes, OCM IV 79). At the min-imum we can conclude that there is no reason to suppose that the two claimsare inconsistent with each other.But the real problem is surely whether ideas can coherently be said to

possess causal properties at all. If ideas were psychological entities, as theyare for Descartes, the problem here would be less striking; the efficacy of ideascould be regarded as a form of mental causality. But as we have seen,Malebranche’s ideas in God are not psychological items at all; they are morenaturally regarded as logical abstract objects belonging to the ‘third realm’. It is

13 In the Entretiens sur la Mort, for instance, Malebranche writes both that ‘l’idée de l’éten-due . . . touche l’ame’ and that ‘Dieu seul . . . agit dans notre ame . . . par l’idée de l’étendue qu’ilrenferme’ (OCM XII 408, 409). See Alquié, Le Cartésianisme de Malebranche, p. 211, note 17.



difficult, to say the least, to see how entities of this kind can be causally activewithin the spatio-temporal world. Malebranche’s only answer to this objectionseems to be the following argument: ideas are in God, and everything that is inGod is efficacious; hence ideas themselves are efficacious (Malebranche to deMairan, 12 June 1714, OCM XIX 884). But it is not clear that Malebranche isreally entitled to the second premise.14 Of course, we must beware of simplyconfronting Malebranche with Humean and Kantian dogmatism concerningcausality; it is unfair and anachronistic to object that nothing can be a causewhich is outside the spatio-temporal order. Yet even within the terms ofMalebranche’s own system, it seems that there are reasons to deny theattribution of causal efficacy to ideas. If God is a cause for Malebranche, it issurely not qua region of ideas but by virtue of his will. Certainly it is in termsof his having a necessarily efficacious will that Malebranche defends his centraloccasionalist thesis that God alone is a genuine cause (SAT 6.2.3, OCM II 316;LO 450).

It is tempting to say that Malebranche is really working with two concep-tions of God which he fails to distinguish. One conception represents God as a‘third realm’ entity: he is the region of ideas, the locus of abstract objects. Theother conception is more traditionally Christian: it represents God as a person(or super-person) endowed with a will and capable of caring for his creatures.Only on this second conception does it make sense to attribute causal proper-ties to God. Tempting as this objection is, it is perhaps a little uncharitable. Wecould say instead that Malebranche could unify his conception of God pro-vided he thought of the divine attributes in a Spinozistic way. To say this is notof course to say that Malebranche should have been led to the doctrine ofinfinite attributes or that he should have identified God with Nature. Thepoint is rather that what Malebranche needs is something like the Spinozisticthesis that God possesses attributes which are insulated from one another; inother words, he needs a conception of God as having attributes between whichthere is no logical flow. Just as Spinoza’s God has both mental and physicalattributes (thought and extension), so Malebranche’s God would have bothmental and, as we might say, logical attributes. Thus to consider God as aperson endowed with a will would be to conceive of him under one attribute;to consider him as the region of ideas would be to conceive of him under adifferent attribute. But causal properties could be predicated of God only quaperson, and not qua region of ideas. To suppose that God could be causallyactive qua region of ideas would be to be guilty of a category mistake.

14 There is also a problem with the first premise of the argument, for it is not altogether clearhow the claim that ideas are in God is to be understood. Ideas cannot be modifications of thedivine substance since, as Malebranche insists in Elucidation X to The Search After Truth,Infinite Being is incapable of modifications (OCM III 149; LO 625). Malebranche’s preferredsolution seems to be that ideas are the divine essence insofar as it is participable by creatures(OCM III 149; LO 625).



Some readers may be tempted to agree that the doctrine of causally effica-cious ideas is incoherent, while resisting the conclusion that Malebrancheshould have embraced a Spinozistic conception of the relationship betweenthe divine attributes. It may be argued that what Malebranche should havesaid is that God acts on the human mind, but in a way that does not imply theattribution of any causal powers to the ideas themselves; rather, God displaysor reveals certain ideas—of bodies, for example—to my mind. This is verymuch the line that Malebranche takes in The Search After Truth where we aretold that we see the idea ‘because it pleases God to reveal it to us’ (3.2.6, OCMI 445; LO 234). But not only does this position give up the doctrine of causallyefficacious ideas; it also seems to require the postulate of a faculty of pureintellect by means of which we apprehend the ideas that God chooses to revealto us. Thus, even if this position is internally coherent, it would not beadequate for Malebranche’s purposes once he had abandoned the Cartesiandoctrine of the faculty of pure intellect.A second problem with the theory of efficacious ideas in its basic form has

been raised by Martial Gueroult.15 Gueroult alleges that there is an incoher-ence in the way in which Malebranche seeks to unpack the metaphor of divineillumination. According to Gueroult, Malebranche regards all the mind’smodalities as obscure, confused, and wholly lacking in cognitive content; yethe also holds that at least some mental states are caused by the action of divineideas. Now insofar as mental states are caused in this latter way, they areilluminated by divine light and thus are clear and distinct, not obscure andconfused. Thus, in the eyes of Gueroult, Malebranche is simultaneouslycommitted to saying that all the mind’s modalities are obscure and confused,and that some are not. But though some of his statements may be unguarded,there does not seem to be a serious difficulty here for Malebranche. Male-branche’s position can be reformulated to avoid this inconsistency, even if aprecise formulation takes some care. It is tempting to express Malebranche’sposition by saying that all and only the mind’s intrinsic modalities are obscureand confused. Yet as we have seen, this is potentially a little misleading,inasmuch as if intrinsic properties are contrasted with interactive properties,then even sentiments are in a sense not intrinsic. If, however, intrinsic proper-ties are contrasted with relational properties, then it seems that even thosestates which the mind has as a result of efficacious ideas can be characterizedin non-relational terms. But perhaps we can reformulate Malebranche’s pos-ition in the following way: all and only those states which the mind has as aresult of the laws of mind–body union are obscure and confused. This isconsistent with the claim that the mind additionally has enlightened modal-ities which are the result of causally efficacious ideas.

15 M. Gueroult, Malebranche, vol. 1 (Paris: Aubier, 1955–59), pp. 189–90.



Gueroult also raises a problem which concerns only the extended versionof the doctrine of causally efficacious ideas. According to Gueroult, Male-branche’s attempt to characterize the differences between types of mentalstates in terms of the various ways in which ideas affect the mind involveshim in a ‘paradox’.16 For Malebranche, a mind which is merely conceiving atriangle is more illuminated by divine ideas than a mind which is sensiblyperceiving a triangular figure; this is simply Malebranche’s way of expressingin Augustinian terms the Cartesian intuition that genuine knowledge requiresone to turn away from sense-experience. Yet a mind which is engaged inconceiving is said to be touched more lightly, or less vividly, by divine ideasthan a mind which is engaged in sensibly perceiving. So it seems, then, that themind is all the more penetrated by the light of divine ideas to the extent that itscontact with them is superficial; in other words, says Gueroult, the more themind is penetrated by divine light, the less it is so penetrated. But the difficultyhere seems to be more verbal than real. Malebranche must, of course, say thata mind is more penetrated by divine light when it is engaged in perceivingrather than sensing; as we have seen, this is simply his belief about thecognitive inferiority of sense-experience which he shares with Descartes. Butthere is no incoherence, no paradox, in saying that the mind achieves a higherdegree of knowledge when the action of divine ideas on the mind is light ratherthan heavy. It is no more paradoxical than the claim that one can hit a ballmore effectively when the stroke of the bat is deft rather than heavy. Male-branche’s claim about the ways in which ideas affect the mind may strike us asbizarre, but it does not suffer from this kind of incoherence.

Some of the difficulties which have been detected in the theory of efficaciousideas can thus be dispelled, but as we have seen, there is one difficulty that is notso easily laid to rest; this is the problem of whether ideas, on Malebranche’sinterpretation, can coherently be said to have causal properties at all. Yet thoughthe doctrine is subject to this difficulty, its motivation is clear; it forms the keyelement in a remarkable attempt to explain divine illuminationwithout recourseto a Cartesian theory of pure intellect. Indeed, in his later philosophy Male-branche wasmoving away fromCartesian assumptions about themind towardsa position which has perhaps more in common with Berkeley’s. Certainly, atleast on the extended version of the doctrine of efficacious ideas, Malebrancheanticipates Berkeley in holding that all the mind’s states (except perhapsvolition) are the result of God’s direct action on the mind. What separatesMalebranche’s theory of mind from Berkeley’s is largely his continuingPlatonic-Augustinian insistence on treating ideas as abstract entities. For thisreason Berkeley could claim with justice that he was not a disciple of Male-branche, but he had more in common with him than he was ready to allow.17

16 Gueroult, Malebranche, vol. 1, p. 190.17 For further discussion of this issue see chapter 17 in this volume.



4

Sensation, Intentionality, and AnimalConsciousness

Malebranche’s Theory of the Mind

Many philosophers have held that intentionality is an essential characteristicof our mental life. Traditionally, this thesis is associated above all with thenames of Husserl and Brentano. Husserl, for instance, writes that ‘the word“intentionality” signifies nothing else than the universal and basic charac-teristic of all consciousness that it is consciousness of something, that,precisely as cogito, it bears within itself its own cogitatum’.1 The Cartesianallusion here seems at least partly appropriate, for though he is difficult topin down, in many of his writings Descartes appears to have assumedsomething like Husserl’s thesis. In general, seventeenth-century philoso-phers after Descartes seem to have simply followed his lead in this area:Leibniz and Spinoza are clear cases in point.2 Perhaps there is only onemajor figure in the period who stands out against the prevailing orthodoxy,and that is Malebranche.

1 Edmund Husserl, Cartesian Meditations, section 14; quoted in Steven Nadler, Arnauld andthe Cartesian Philosophy of Ideas (Manchester: Manchester University Press, 1989), pp. 143–4.Earlier versions of this essay were presented to a symposium: ‘Ideas and Representation inDescartes, Malebranche, and Foucher’, American Philosophical Association Pacific Divisionmeeting, Portland, March 1992, and to a discussion group at the University of California, SanDiego. I am particularly grateful to John Cottingham, Philip Kitcher, Michael Mendelson, StevenNadler, and Marleen Rozemond for helpful comments.

2 Jonathan Bennett, for example, writes of Spinoza’s ‘deep assumption that it is of the essenceof the mental, as such, that mental items are representative, about something, pointed outwards’.A Study of Spinoza’s Ethics (Cambridge: Cambridge University Press, 1984), p. 155. Leibniz’scommitment to the intentionality thesis is implicit in his thesis that perception is a species ofexpression.


I

Like most philosophers, Malebranche believes that intentionality is a feature ofmuch of our mental life; we spend a lot of our time perceiving and thinkingabout things. Malebranche’s theory of such intentionality is distinctive and setshim apart frommore orthodoxCartesians. The distinctive character of his viewscan be brought out in the following way. Arnauld, and probably Descarteshimself, hold what might be called a content theory of intentionality; theybelieve that intentionality is an intrinsic feature of mental acts themselves.3

Thus when I think of or perceive the sun, for example, there is something aboutthe act of thinking or perceiving by virtue of which it is a thought or perceptionof the sun. Malebranche, by contrast, subscribes to an object theory of inten-tionality; he holds that the intentionality of mental acts is to be explainedin terms of their being directed to independently existing objects. For Male-branche, the objects towards which my mind is directed are always ideas, butideas are not mental items, as they are for Descartes. Distinguishing sharplybetween the provinces of logic and psychology, Malebranche insists that theobjects of thought, unlike particular acts of thinking, must be understood in aPlatonic way as abstract entities; such entities have a locus which Malebrancheidentifies with God.4When I think of the sun, for example, my act of thinking isdirected to one of God’s ideas or logical concepts. In contrast to Descartes andArnauld, Malebranche thus believes that the intentional relation is an ordinaryrelation between two ontologically distinct entities. It would be natural tosuppose that Malebranche would restrict such a theory of intentionality to thecase of abstract thought, but astonishingly this is not the case; Malebrancheextends his theory to cover the case of sense-perception as well. At the risk ofsome simplification, we can say that, for Malebranche, even when I perceive thesun, mymind is immediately directed at God’s concept or idea of the sun.5 Thuswe come to Malebranche’s famous or notorious thesis that we see all thingsin God. One may be tempted to object that such a theory seems to leave outeverything that makes my perception sensory rather than intellectual, but as weshall see, Malebranche has a way of coping with this objection.

It is important to note that Malebranche’s object theory is a thesis about thenature of intentionality; it is not a theory about how far intentionality extends.

3 For a fine account of the two theories, see Nadler, Arnauld, ch. 4.4 God plays a role in Malebranche’s theory of ideas analogous to that of the ‘third realm’ in

Frege. For more on the distinction between logic and psychology in Malebranche’s theory ofideas, see Nicholas Jolley, The Light of the Soul: Theories of Ideas in Leibniz, Malebranche, andDescartes (Oxford: Clarendon Press, 1990), ch. 4, and Steven Nadler, Malebranche and Ideas(Oxford: Oxford University Press, 1992), esp. ch. 2.

5 In his later philosophy, beginning with Elucidation X to The Search After Truth, Malebranchedenies that, strictly speaking, there are ideas of particular physical objects in God. Rather, there isjust the one idea—intelligible extension—which God applies to our minds in different ways.



It is thus completely neutral on the question of whether all or only some of ourmental states are intentional. There is nothing in the theory which precludesMalebranche from saying that all our mental states are directed at independ-ently existing abstract objects—ideas or logical concepts in God. Indeed,Malebranche can go further and say that it is even essential to mental statesto be directed at such objects. Thus intentionality could be an essential, rela-tional property of mental acts, even though it is not an intrinsic one. Analo-gously, one might say, it is essential to me to be someone’s offspring, eventhough this property is not intrinsic to me. This is certainly a possible positionbut, as I shall argue, it is not in fact the one he adopts. Malebranche holds thatthere is a large class of mental states—namely, sentiments or sensations—whichare not intentional at all. Into this class Malebranche puts not merely bodilysensations such as pain and pleasure but all the secondary qualities as well.We can see from the preceding analysis why Malebranche must deny

intentionality to sensations. Malebranche is explicit that sensations are modi-fications of the soul (SAT 3.2.6, OCM I 445; LO 234), and thus by virtue of his‘object theory’, they cannot be intrinsically intentional. Thus the only way inwhich sensations could have intentionality is if they were directed to inde-pendently existing objects—ideas in God; but on Malebranche’s view, they arenot. Malebranche regularly speaks of ideas as being perceived, but he does notclaim that they are sensed;6 indeed, since ideas are universals, it is clear thatsuch a claim would be incoherent. Rather, he holds that sensations typicallyoccur in conjunction with the perception of ideas. It is this view which isexpressed in a famous passage from The Search After Truth:

When we perceive something sensible, two things are found in our perception:sensation and pure idea. The sensation is a modification of our soul, and it is Godwho causes it in us. He can cause this modification even though He does not have itHimself, becauseHe sees in the ideaHe has of our soul that it is capable of it. As for theidea found in conjunction with the sensation, it is in God, and we see it because itpleases God to reveal it to us. God joins the sensation to the idea when objects arepresent so thatwemay believe them to be present and thatwemayhave all the feelingsand passions we should have in relation to them.

(SAT 3.2.6, OCM I 445; LO 234)

Thus although sensations may occur in conjunction with perceptions of ideas,in themselves they are not intentional. In the same way one might say thatfeelings of anxiety can occur in conjunction with thoughts which have content,but the feelings of anxiety themselves are not intentional.

6 In the Dialogues on Metaphysics V.6, Malebranche writes of ideas of bodies becomingsensible, but the context indicates that he means that ideas of bodies are perceived in conjunctionwith sensations (OCM XII 117; JS 78).


Sensation, Intentionality, and Animal Consciousness 59

One thing which emerges clearly from our analysis so far is that sensationsplay a very important role in Malebranche’s philosophy of perception. Male-branche holds that, even in sense-perception, our minds are related to ideas inGod; such ideas are typically concepts of geometrical universals, and it is byvirtue of our relation to these concepts that we are able to judge, for example,that a given body is spherical or rectangular.7 But, as Malebranche sees,although such a judgement is an important element of sense-perception, itcannot constitute it entirely; in perceiving the sun, for example, we do notmerely apply the geometrical concept of a sphere, we have colour sensations aswell. It is the presence of sensations, then, which accounts for the genuinelysensory character of sense-perception, and thus qualifies what would other-wise be an austerely intellectual account.8

Before we conclude this section we need to spell out the full ontologicalsignificance of Malebranche’s distinction between ideas and sensations.According to Malebranche, the mind participates in two kinds of union witha substance other than itself. The mind is related to ideas in thinking andperceiving by virtue of its union with God who is their locus; the mind hassensations, by contrast, by virtue of its union with the body (where physicalstates of the brain serve as occasional causes of sensations).9 Now Male-branche insists that whereas a mind’s union with God is necessary, its unionwith its body, while natural, is merely contingent;10 thus there could be ahuman mind which did not experience sensations, and such a possibilitybecomes actual in the case of the afterlife. By contrast, there could not be ahuman mind which enjoyed no access to divine ideas. But although it couldnot be a human mind, it seems conceivable on Malebranche’s principles thatthere should be a soul which was united only to its body. The logical possibilityof such a soul will become important in the final section when we discussMalebranche’s reasons for accepting the Cartesian doctrine of the beast-machine.

7 Malebranche’s emphasis on the element of judgement in sense-perception may be seen as adevelopment of Descartes’ thesis that bodies are perceived through the intellect. OnMalebranche’sadaptation of Cartesian themes in his theory of vision in God, see Jolley, Light of the Soul, ch. 3.

8 It is not entirely clear whether Malebranche holds that there are sensations of primaryqualities. Early in The Search After Truth (SAT 1.7.4) Malebranche seems to think there are; hewrites of our sensations of size and shape and calls them ‘natural judgments’ (OCM I 97; LO 34).Such a theory seems inconsistent with what appears to be the dominant position of Male-branche’s mature philosophy, namely, that our ability to make perceptual judgements aboutprimary qualities is logically dependent on our being related to ideas in God.

9 For a full account of these unions see DMR XIII.9, OCM XII 319–20; JS 252–3.10 ‘The relation that minds have to God is natural, necessary, and absolutely indispensable;

but our mind’s relation to our body, although natural to our mind, is neither absolutely necessarynor indispensable.’ SAT, Preface, OCM I 10; LO xx.



II

Malebranche’s thesis that sensations are non-intentional enables us to makesense of one of his most notorious doctrines. In Elucidation XI to The SearchAfter Truth there occurs a passage which caused Malebranche to be ridiculedas a believer in the rainbow-coloured soul. Malebranche advances a theory ofcolour here in the course of criticizing Descartes’ thesis that the mind is betterknown than body; in opposition to Descartes he seeks to show that whereaswe have a clear idea of body, we do not have a clear idea of the soul.Malebranche’s argument for this radically anti-Cartesian thesis turns on theexistence of controversy regarding the status of sensible (i.e. secondary)qualities. In the eyes of Malebranche, the fact of there being such radicallyopposing views is sufficient to show that we do not have the clear idea of themind that the Cartesians suppose we do. Malebranche then introduces hisown radical view of the status of colour here as a further contribution to thedebate. Although he is aware that his theory is controversial, he clearly thinksthat it is the correct one:

You even make a fool of yourself before certain Cartesians if you say that the soulactually becomes blue, red, or yellow, and that the soul is painted with the coloursof the rainbow when looking at it. There are many people who have doubts, andeven more who do not believe, that when we smell carrion, the soul becomesformally rotten, and that the taste of sugar, or of pepper or salt, is somethingbelonging to the soul. Where, then, is the clear idea of the soul so that theCartesians might consult it, and so that they might all agree on the question asto where colours, tastes, and odours are to be found?

(SAT, Elucidation XI, OCM III 166; LO 634–5)

Malebranche may overstate his case here somewhat, but much of what he saysis, I believe, defensible; he is advocating something like a non-intentional,adverbial theory of sensations.It is not of course difficult to see why Malebranche’s theory of the rainbow-

coloured soul should have come in for ridicule. The theory does indeed soundodd; it sounds odd for the obvious reason that ordinary language embodiesthe commonsense, pre-Cartesian assumption that colours and other second-ary qualities are straightforwardly categorical properties of bodies on a parwith size and shape. But of course no serious Cartesian could reject thedoctrine merely on the grounds of its linguistic oddity; although he mightbe tempted to appeal to ordinary language for polemical purposes, he cannotattach any real weight to such considerations. For the Cartesian must beprepared to admit that ordinary language embodies a host of metaphysicalmistakes to which the unreflective, pre-philosophical consciousness is natur-ally prone. What, then, is at issue between Malebranche and these hostileCartesians?



In the first place, Descartes is at least sometimes prepared to treat secondaryqualities as properties of bodies. Of course Descartes does not think thatcommon sense is right in regarding such qualities as straightforwardly cat-egorical properties of bodies: that view is profoundly mistaken. But there areplaces in his writings where Descartes anticipates the official Lockean doctrineabout secondary qualities; they are powers in bodies to produce ideas (i.e.sensations) in us.11 In the Principles of Philosophy Descartes writes:

we have every reason to conclude that the properties in external objects to whichwe apply the terms light, colour, smell, taste, sound, heat and cold—as well as theother tactile qualities and even what are called ‘substantial forms’—are, so far aswe can see, simply various dispositions in those objects which make them able toset up various kinds of motions in our nerves which are required to produce allthe various sensations in our soul.

(Principles of Philosophy IV.198, AT VIIIA 322–3; CSM I 285)

According to this view, secondary qualities are dispositional and relationalproperties of bodies.12 From this standpoint the doctrine of the rainbow-coloured soul represents something like a category mistake.

Perhaps the view more commonly associated with Descartes and his dis-ciples, however, is that secondary qualities are strictly mind-dependent. So onthis view, Malebranche is at least right that colours, sounds, tastes, and smellsare in minds, not bodies. Yet even if Descartes and his disciples adopt this line,they are not thereby committed to holding that the mind actually instantiatesall the colours of the spectrum in looking at the rainbow; Malebranche is rightto suspect that there is still a point at issue between himself and more orthodoxCartesians. The orthodox Cartesian would deny that redness, for example, isstrictly a modification of the mind. In the technical jargon, the mind cannotbecome formally red; rather, talk of redness enters in when we are engaged inspecifying the objective reality of an idea. To say that I have a sensation of red isto say that I have an idea with a certain content. Perhaps the Cartesian would gobeyond this rather minimal specification of content in terms of my idea’s beingan idea of red; he might also say that, in cases of veridical perception, to have asensation of red is to have a confused representation of certain primaryqualities of a body—e.g. the texture of the particles on its surface. But in anycase, on either account, a sensation of red is an idea with a certain content to it.

It is over this last issue that Malebranche and more orthodox Cartesians arereally divided. What sets Malebranche apart from his fellow-disciples is not somuch his unwavering commitment to the strict mind-dependency of second-ary qualities; it is rather his commitment to the thesis that secondary-quality

11 Cf. John Cottingham, ‘Descartes on Colour’, Proceedings of the Aristotelian Society 90(1989–90), pp. 237–8.

12 See chapter 2, n. 19 in this volume.



sensations have no content or object, are not intentional. To deny that sensa-tions have content or an object is not, of course, to preclude the possibility ofgiving an account of how seeing red differs from seeing blue, for example; onthe contrary, the difference can be explained in purely adverbial terms. To havea sensation of red is to sense redly, to have a sensation of blue is to sense bluely,and so on, for all the colours of the rainbow. It is, I suggest, this adverbial theoryof sensations which underlies Malebranche’s doctrine of the rainbow-colouredsoul. Such a theory is one which finds supporters even today.13

It must be admitted that my interpretation stops a little short of whatMalebranche actually says in Elucidation XI. According to the adverbialtheory, the mind senses bluely and redly in looking at the rainbow; accordingto Malebranche’s actual words, the mind becomes blue and red on thisoccasion. Thus taken at face value, Malebranche’s theory of sensation is notso much adverbial as adjectival, as it were. But I think that Malebranche maybe exaggerating his views here. For Malebranche can hardly deny that whenI look at the rainbow, I am engaged in an act of sensing. The question thenarises: ‘How am I sensing?’, and to this the answer will be: ‘I am sensing redly,bluely, and so on’.Malebranche may have been encouraged in this exaggeration by a deep

metaphysical impulse—the desire to tidy up Cartesian dualism. At first sightthis may seem a surprising claim, for Malebranche is not really a dualist at all;he is more like a ‘trialist’ who acknowledges, in addition to the realms of mindsand bodies, a further third realm of irreducibly abstract entities: ideas in God.But however that may be, there is a tendency in his philosophy to preserve asmuch symmetry as possible between mind and matter, and I suspect thattendency is at work here. For on the Cartesian metaphysics of matter whichMalebranche largely shares, the intrinsic properties of bodies are indeedadjectival; they are geometrical properties like being cuboid or spherical.Thus symmetry requires that the intrinsic properties of bodies must also beadjectival. It is, I suspect, this condition which Malebranche is seeking to meetin his theory of sensations. Malebranche may have been mistaken in suppos-ing that he could achieve this degree of symmetry; the adverbial theory of theintrinsic states of the mind is the furthest that he can justifiably go in thisdirection.14

13 See M. Tye, ‘The Adverbial Approach to Visual Experience’, Philosophical Review 93 (1984),195–225. The claim thatMalebranche offers an adverbial theory of sensation is also found inNadler,Malebranche and Ideas, p. 64. Nadler, however, does not discuss the theory in detail.

14 It may be objected that Malebranche describes our sensations as being confused (e.g. DMRIII.4, OCM XII 65; JS 33), and this suggests that they are intentional. Malebranche may be simplyusing a standard Cartesian term for portraying sensations in a negative epistemological light. OrMalebranche’s point may be that sensations are characteristically accompanied by the falsejudgement that they convey information about the world. Strictly speaking, it would not bethe sensation but the judgement that was confused.



I I I

The interpretation of Malebranche’s theory of sensations has implications forother parts of his system which at first sight may seem remote from it. In thissection I shall argue that Malebranche’s views on the status of animals can bemisunderstood if one fails to appreciate the non-intentional character ofsensations.

One of Descartes’ most notorious doctrines is that animals are meremachines which are wholly devoid of consciousness. Such a doctrine seemsso obviously counter-intuitive that it has been aptly named ‘the monstrousthesis’.15 In their book, Animal Consciousness, Daisie and Michael Radneraddress the question of why Malebranche accepted this thesis.16 The questionis well worth asking. It is not enough to point to the fact that Malebranche is aCartesian; as we have seen, he was no mere slavish disciple, but an originalthinker prepared to depart from Cartesian orthodoxy on a number of issues.According to the Radners, although Malebranche offers theological argumentsin favour of the beast-machine thesis, his real reasons for accepting thedoctrine have to do with the internal pressures of his philosophical system.In their view, Malebranche sees that he would be forced to extend his doctrineof vision in God to animals if he were to allow that animals have sensations:

What happens if animals are allowed sentiments of color, pain, and so on? Suchmental acts must have objects, for to see nothing is not to see and to feel nothingis not to feel. The object cannot be material, otherwise animals would haveimmediate and direct knowledge of bodies—a feat which not even God himselfcan accomplish . . . If the analysis of generality is not to be undermined, animalsmust be granted access to the ideas in the efficacious substance of the Divinity.Animals, too, would sense nothing but what God makes them sense. In him toothey would live and move and have their being. He would be the true light thatenlightens every animal.17

So on this interpretation Malebranche is impaled on the horns of a dilemma:either he must follow Descartes in defending the monstrous thesis or he mustextend his doctrine of vision in God to animals. But Malebranche cannotembrace the latter horn without getting into theological difficulties; the

15 This phrase is the cheerful coinage of Norman Kemp Smith. See his New Studies in thePhilosophy of Descartes (New York: Russell and Russell, 1963), pp. 135f.

16 Daisie Radner and Michael Radner, Animal Consciousness (Buffalo: Prometheus Books,1989), pp. 70–91. Malebranche’s commitment to the ‘monstrous thesis’ is unequivocal: ‘Thus inanimals, there is neither intelligence nor souls as ordinarily meant. They eat without pleasure, crywithout pain, grow without knowing it; they desire nothing, fear nothing, know nothing; and ifthey act in a manner that demonstrates intelligence, it is because God, having made them inorder to preserve them, made their bodies in such a way that they mechanically avoid what iscapable of destroying them.’ SAT 6.2.7, OCM II 394; LO 494–5.

17 Radner and Radner, Animal Consciousness, pp. 75–6.



prologue to St John’s gospel speaks of men, not animals. So Malebranche optsfor the first horn of the dilemma and thus remains loyal in this instance toCartesian orthodoxy. For Malebranche, then, it is particularly urgent to defendthe beast-machine thesis if he is not to discredit his doctrine of vision in God.This diagnosis is ingenious, but as should be clear by now, it rests on a faulty

understanding of Malebranche’s theory of sensations. The Radners correctlysee that sensations are not themselves ideas; they are not objects to which themind is related in thinking. But they wrongly suppose that sensations, by virtueof being mental acts, must have objects which can be nothing other than ideasin God. In support of this reading they adduceMalebranche’s many statementsto the effect that ‘nothingness is not perceptible’ and that ‘to see nothing is notto see’ (see, e.g. SAT, 4.11.3, OCM II 99; LO 320). Such statements express aprinciple which certainly plays an important role in Malebranche’s theory ofintentionality; it helps to explain his commitment to the object theory ratherthan the content theory. But the scope of the principle is strictly limited; itapplies to seeing and perception, but not to sensing. It is true that Malebrancheuses ‘see’ (voir) and ‘perceive’ (appercevoir) in a broad sense which covers bothabstract thought and what we would call sense-perception. But in both casesthe objects of such mental acts are primary qualities, whether or not suchqualities are instantiated. Thus the principle which the Radners invoke has nobearing whatever on the case of sensations. It is significant that the Radnerssaddle Malebranche with the thesis that to feel nothing is not to feel, but theyare unable to provide any textual support.Perhaps the Radners would hold that, though sensations are not themselves

directed at objects, they must occur in conjunction with mental acts which areso directed. Thus, I cannot merely have a sensation of red; I must perceive acertain shape which looks red to me (whether I am hallucinating or perceivingveridically). If that is the claim, then it is tantamount to conceding Male-branche’s commitment to the non-intentional, adverbial theory of sensations:to have a sensation of red is to sense redly (in conjunction with the perceptionof a certain shape). But in any case it does not seem plausible to suppose thatMalebranche would concede this thesis in its full generality, for the class ofsensations includes not only secondary qualities but also pain and pleasuresensations, and it is difficult to believe that Malebranche thought that suchsensations must be accompanied by the perception of primary qualities.There is no case for saying, then, that Malebranche’s commitment to animal

automatism in The Search After Truth is motivated by a fear of compromisinghis doctrine of vision in God.18 Indeed, by virtue of the anti-Cartesian

18 In his later philosophy (from around 1695) Malebranche sometimes claims that all themind’s (non-volitional) states, including sensations, are the results of God’s efficacious ideas. See,e.g., a late addition to the Conversations chrétiennes, OCM IV 75–6. In terms of this theory, then,it would be correct to say that union with God is a necessary condition of the mind’s having



innovations in his philosophy of mind, Malebranche is in a position toadvance a rather interesting theory of animal consciousness. Here we mustrecall Malebranche’s doctrine that the human mind is involved in two kinds ofunion. By virtue of its union with God, it has the capacity to perceive the ideaswhich God discloses to it; in this sense it sees all things in God. By virtue ofits union with its body it has the capacity to have sentiments or sensations. Itseems open to Malebranche to hold, then, that unlike the human mind, theanimal soul participates in only the one kind of union—the union with itsbody. Malebranche could thus concede that animals do not fall within thescope of the vision in God doctrine; God is not the light which enlightensevery animal. Nonetheless, even though animals have no epistemic access toGod’s ideas, by virtue of their union with their bodies, their souls have the fullrange of sensations. Such a theory would allow that, though animals havesome consciousness, it is of a more rudimentary kind than that which humansenjoy. It is true that such a theory might not accord exactly with our (non-Cartesian) intuitions. On the interpretation I favour, epistemic access to ideasin God is a necessary condition for all judgement about primary qualities;thus, by being deprived of such access, the cat, for example, would not be ableto see that there was a circular dish in front of it. The mental world of animalswould be one of ‘blooming, buzzing confusion’. We may feel that animalconsciousness is a little more developed than this. Nevertheless, Malebranchewould still be in a position to accommodate the central intuition aboutanimals which Descartes so strikingly flouts—namely, that they are capableof feeling such sensations as hunger and pain.

Malebranche, then, has the philosophical resources to develop an interest-ing theory of animal consciousness. Unlike Descartes, he is not committed tothe thesis that sensation is a confused form of thought, and thus he does notface Descartes’ problem that we cannot attribute sensation to animals withoutalso attributing to them a faculty of thinking. Why, then, did Malebranchesimply follow Descartes in accepting the counter-intuitive thesis of the beast-machine? Sometimes, like Descartes, Malebranche appeals implicitly to aversion of the Principle of Parsimony: since all animal behaviour can beexplained in terms of mechanistic principles, it is simply superfluous, froman explanatory point of view, to postulate the existence of an animal soul (SAT4.11.3, OCM II 106; LO 324). More characteristically, however, Malebranchedeparts from Descartes by presenting theological arguments in favour of the

sensations. However, this is not the position of The Search After Truth, and such later develop-ments of Malebranche’s philosophy cannot be invoked to explain his adoption of the doctrine ofthe beast-machine from an early date. On the development of Malebranche’s philosophy and the‘extension of vision in God to the realm of sensation’, see A. Robinet, Système et existence dansl’oeuvre de Malebranche (Paris: Vrin, 1965), Book II, chs. 3–4, esp. pp. 273–5, and F. Alquié, LeCartésianisme de Malebranche (Paris: Vrin, 1974), pp. 209–10.



beast-machine doctrine; such arguments tend to display the Augustinian sideof Malebranche’s inheritance.Malebranche’s most prominent argument for the beast-machine doctrine is

an exercise in theodicy; it turns on the divine attribute of justice. The essenceof the ‘argument from divine recompense’, as it has been called, is easilystated.19 Since animals are innocent (sinless), if they suffer, then either theyare recompensed for their sufferings or God is unjust. But God is not unjust,and animals are not recompensed; there is no ‘heaven’ for animals.20 Hence,animals do not suffer. (This conclusion stops a little short of the thesis thatanimals are mere machines, but it does embody the strikingly counter-intui-tive thesis that they feel no pain.) The difficulty with this argument is clear. Asthe Radners note, Malebranche provides no real support for the premise thatanimals are not recompensed; he gives us no good reason to believe that thereis no heaven for animals. It is true that the Bible is silent on this issue, but thatshows little. The Bible is addressed to human beings and preaches a messageabout human salvation; the fate of animals is simply irrelevant to this purpose.It is the apparent weakness of this argument and others which leads the

Radners to look around for deeper reasons that Malebranche may have had foraccepting the monstrous thesis.21 Such an interpretative strategy is of courseopen to criticism; from the fact that an argument appears obviously weak to usit hardly follows that Malebranche thought it less than conclusive. Moreover,as we have seen, Malebranche does not rely exclusively on theological argu-ments for the beast-machine doctrine; sometimes, like Descartes, he appeals tothe Principle of Parsimony. Thus there is no compelling reason to concludethat Malebranche’s official arguments do not represent his real case for thebeast-machine doctrine.A standard criticism of philosophers in the Cartesian tradition is that they

fail to do justice to the diversity of mental phenomena. Richard Rorty hascomplained with some reason that, through the umbrella use of the term ‘idea’,Descartes and Locke are led to construe all mental states as intentional.22 Such atheory overlooks the fact that there are mental states, such as pain sensations,which do not represent, which are not about anything. Faced with this kind of

19 This is the name given to the argument by Radner and Radner who also providea detailed reconstruction. See Animal Consciousness, pp. 85–91. Their chief source isMalebranche’s Défense . . . contre . . . de la Ville, OCM XVII-1 513–18.

20 Radner and Radner, Animal Consciousness, p. 90.21 Malebranche also presents a simpler version of the argument from divine recompense

which is perhaps more satisfactory. This version employs the strong premise that any sufferingon the part of animals is inconsistent with divine justice (SAT 4.11.3, OCM II 106; LO 323). Thusthis argument allows Malebranche to dispense with the dubious assumption that there is noheaven for animals. Although the key premise is rather strong, from a theological standpoint it issurely rather intuitive.

22 Richard Rorty, Philosophy and the Mirror of Nature (Princeton: Princeton University Press,1979), ch. 1, pp. 27–8.



objection Descartes is led to ‘gerrymander’ by claiming that such states arereally intentional after all; they are confused representations of physical states.By contrast, Malebranche is not attracted to this kind of manoeuvre; he offersan adverbial, or quasi-adverbial, theory of sensations (sentiments) which rec-ognizes their straightforwardly non-intentional character. Thus, despite hisallegiance to Descartes in many respects, Malebranche is not vulnerable to oneof the major criticisms that have been levelled against his master.

Malebranche’s philosophy of mind is thus, in important respects, superiorto that of Descartes; indeed, it embodies an insight into mental phenomenawhich seems to have eluded all his famous contemporaries. We may stillwonder why Malebranche seems to have been alone among seventeenth-century philosophers in recognizing a class of non-intentional mental states.Any answer to this question must be speculative, but it is worth pondering therole that theological factors may have played in leading him to this doctrine.As a theologian in the Augustinian tradition, Malebranche believed that it wasnecessary to emphasize the mind’s lack of cognitive self-sufficiency; as Male-branche puts it, ‘man is not a light unto himself ’ (DMR III.7, OCM XII 67; JS35). Philosophically, this commitment was expressed in his distinctive versionof the object theory of intentionality: in order to perceive or think, the mindmust be related to objects, and these objects can only be ideas in God. Now aswe have seen, such a theory of intentionality is consistent with holding thatevery mental state is essentially intentional, even though none is intrinsicallyso. It may seem, then, that there is no route from the doctrine of divineillumination to Malebranche’s denial that mental states are essentially inten-tional. But a philosopher such as Malebranche who seeks to emphasize themind’s lack of cognitive self-sufficiency may well find it useful to be able toshow, by means of concrete examples, just how impoverished our mental life iswhen it is not assisted by divine illumination. And if there are mental stateswhich are wholly lacking in content, then they would amount to impressiveevidence of the mind’s cognitive impotence when left to its own resources.In this way, perhaps, Malebranche’s theological resources may have at leastpredisposed him towards the thesis that intentionality is not the mark of themental. But however that may be, Malebranche made an important philo-sophical contribution to our understanding of the mind. He avoided themistake of assimilating such disparate items as sensations and beliefs, and ingeneral he resisted the temptation to suppose that mental phenomena aremore homogeneous than they really are. Malebranche pioneered an approachto the nature of sensation from which philosophers can still learn.



5

Malebranche on the Soul

Few periods are more important in the philosophy of mind than the seven-teenth century. The new mechanical picture of the physical world confrontedmany philosophers with an exciting challenge: they needed to formulatetheories of the mind which were not only philosophically more defensiblebut also better adapted to the needs of Christian theology than their traditionalAristotelian-Scholastic rivals. Although many of the theories that were ad-vanced are widely rejected today, there is no doubt that they left a decisivemark on subsequent thinking; indeed, they helped to define the contemporaryagenda in the philosophy of mind. For instance, current debates over themerits of dualism and materialism are often clearly of seventeenth-centuryinspiration. Other thinkers in the period may have had a more direct impacton modern philosophy of mind, but few, if any, are more interesting thanMalebranche.Malebranche’s interest and importance as a philosopher of mind are in

one way surprising. Malebranche is generally classified as one of the Carte-sians, and it is certainly true that he accepted much of the Cartesian philo-sophical framework. It might, then, be expected that Malebranche wouldoffer no more than a series of minor amendments to Descartes’ teaching inthis area. Such, however, is not the case. Partly under the influence of hisother mentor, Augustine, Malebranche was able to break decisively withCartesian orthodoxy on a number of issues in the philosophy of mind. Inthe first half of this essay we shall see that, armed with the theological sloganthat the human mind is not a light to itself, Malebranche pioneers anti-Cartesian theses about the nature of the intellect and sensations. In particu-lar, he challenges the still widely-held view that intentionality is a mark ofthe mental. In the second half of the essay, we shall examine Malebranche’sattack on Descartes’ claims concerning self-knowledge. Here we shall see thatMalebranche advances a powerful internal critique of Descartes; he arguesconvincingly that Descartes’ famous thesis that the mind is better knownthan the body is inconsistent with some of his central commitments con-cerning the nature of knowledge.


I

The radicalism of Malebranche’s critique of Descartes is not always apparent,for in places, such as the first half of The Search After Truth, he seemsstraightforwardly to accept the basic features of Descartes’ ontology of mind.According to Malebranche, the mind is a substance whose whole essenceconsists in thought (SAT 3.1.1, OCM I 381; LO 198); and it has two principalfaculties: the will and the understanding (SAT 1.1, OCM I 40–1; LO 2). In thespirit of Descartes, Malebranche also makes a further distinction regarding theunderstanding. When used without qualification, the term ‘understanding’must be taken in a broad sense to mean ‘the passive faculty of the soulby means of which it receives all the modifications of which it is capable’(SAT 1.1, OCM I 43; LO 3); the understanding in this sense is involved in bothsense-perception and imagination. However, later in the work Malebrancheintroduces us to the notion of the pure understanding; it is by means of thisfaculty that the mind is aware of wholly intellectual ideas such as the conceptsof geometry. As for Descartes, then, the operations of the pure understandinginvolve nothing like the manipulation of sensory images and they are causallyindependent of the activity of the brain (see SAT 3.1.1, OCM I 381; LO 198).

Malebranche never officially broke with Cartesian orthodoxy on theseissues in the ontology of mind, but from the beginning of his career hisphilosophy is subject to the pull of a non-Cartesian theme. Self-consciouslyfollowing Augustine and other Church Fathers, Malebranche insists that themind is not a light to itself (SAT 3.2.5, OCM I 434; LO 229). Just what such aclaim involves may not be clear in matters of detail, but its general tendency isnot in doubt: it suggests a much bleaker picture of the mind’s native cognitiveresources than we encounter in Descartes. Thus, even in early works, such asThe Search After Truth, we find that the mind, for Malebranche, does not havea pure intellect in anything like the full Cartesian sense; that is to say, it is notstocked with innate ideas and truths that the finger of God has implanted in it.Indeed, it has no native resources for finding knowledge, or even the seeds ofknowledge, in itself. At most, it possesses a capacity for attending to objects ofthought whose locus—the mind of God—is external to it.

At least in his later writings, Malebranche’s break with Cartesian orthodoxyis arguably more radical in nature. Malebranche comes to deny not merelythat the human mind has any native resources for drawing concepts fromitself, but also that it has any native resources for apprehending conceptswhose locus is external to it. Malebranche now insists on a very strict inter-pretation of the patristic doctrine that the mind is a lumen illuminatum(illuminated light), not a lumen illuminans (illuminating light); it must beunderstood to mean that the mind achieves knowledge not by exercisingany native capacities of its own, but wholly by virtue of God’s action in



illuminating it by means of efficacious ideas. As Malebranche never tires ofrepeating, the mind finds only the darkness of sensations in itself:

Created reason, our soul, the human mind, the purest and most sublime intellectscan indeed see the light; but they cannot produce it or draw it from their ownresources, nor can they engender it from their substance. They can discovereternal, immutable, necessary truths in the divine Word, in the eternal, immut-able, necessary Wisdom, but in themselves they can find only sensations oftenquite lively, yet always obscure and confused, only modalities full of darkness.

(DMR III.4, OCM XII 64–5; JS 32–3)

Thus, if we say that Malebranche continues to recognize a faculty of pureintellect, it is only in the very minimal sense of a passive capacity to be affectedby God’s efficacious ideas.Malebranche’s insistence that the mind finds only the darkness of sensations

in itself has a further consequence for his break with Cartesian orthodoxy in theontology of mind. As we have seen, Malebranche seems straightforwardly toecho Descartes’ famous claim that the mind is an essentially thinking substance;it is doubtful, however, whether this formulation can have quite the samemeaning in his philosophy. Descartes is perhaps most usually read as assertingthat it is thought, in the sense of consciousness, that constitutes thewhole essenceof mind; on this view, abstract thoughts (e.g. of God and triangles) and sensa-tions of pain and hunger are on a par as modes of thinking. However, as somecommentators have noticed, Descartes often seems to intend his central thesisabout themind in a stronger sense: it is thought in the sense of pure intellect thatconstitutes the essence of mind.1 On this view, sensations of pain and hunger arenot so much modes of thinking as properties of a third substance, the wholehuman being, which is a composite of mind and body. In addition, in favour ofthis view, it can be pointed out that, for Descartes, a disembodied mind wouldhave no states that were not purely intellectual in nature. By contrast, Male-branche holds that the mind finds only sensations in itself, and it is thus difficultto see how he could hold that it is essential to the mind to be a pure intellect. IfMalebranche wishes to retain the Cartesian formula that the mind is an essen-tially thinking substance, it seems that he must understand ‘thought’ in a broadsense that embraces sensations and sense-perceptions.Perhaps it will be objected that the issue is not as simple as this. It is true

that Malebranche is committed to the thesis that sensations alone are intrinsicto the mind; that is, they alone are its non-relational properties. However, tosay that they are intrinsic to the mind is not to resolve the question of themind’s essence. In The Search After Truth, Malebranche observes that it isessential to human minds to be related to God (SAT, Preface, OCM I 10; LOxxxiv), and even in his later writings he never seems to withdraw this claim. By

1 See, e.g., M.D.Wilson,Descartes (London: Routledge and Kegan Paul, 1978), pp. 181, 200–1.


Malebranche on the Soul 71

virtue of this relationship to God, the mind is capable of perceiving ideasor objects of purely intellectual awareness; in this way, then, we might seekto defend the claim that intellect is essential to the mind. However, such adefence of Malebranche’s Cartesianism runs into two problems. In the firstplace, the most that can be said is that intellect is one of the mind’s essentialproperties; it can hardly be said to constitute its whole essence. Secondly, atleast in his later writings, the mind perceives ideas in God solely by virtue ofthe action of God’s efficacious ideas.2 As we have seen, then, to say that themind has a faculty of pure intellect is thus only to make the minimal claim thatthe mind has a passive power to be affected by God’s efficacious ideas. Such athesis is very remote from Cartesian orthodoxy.

Whether or not theMalebranchianmind can be said to have a faculty of pureintellect, there is no doubt that throughout his career Malebranche holds thatpure perceptions number among its states; the mind has pure perceptions, forexample, when it apprehends the concept (idea in God) of a triangle or a circle(Conversations chrétiennes III, OCM IV 75–6). Malebranche’s insistence thatthe mind has such perceptions in addition to obscure sensations gives rise to aproblem of consistency. On the one hand, Malebranche claims that the mindhas pure perceptions to the extent that it is enlightened by ideas in God. On theother hand, he is no less insistent, as we have seen, that the mind finds in itselfonly obscure and confused sensations. Martial Gueroult states the problem bysaying that Malebranche’s argument for the vision in God seems to commithim to saying that the soul both is and is not enlightened by divine ideas.3

One commentator, Tad Schmaltz, tries to solve the problem of consistencyby drawing on the fact that perception, for Malebranche, is essentially rela-tional; that is, it involves a relation between the human mind and ideas in God.However, any perception can be considered in terms of its intrinsic or non-relational properties, and when it is considered in this way, it is merely asensation, and as such, obscure and confused.4 Schmaltz’s point here can beclarified by means of an analogy. To speak of someone as a father is of courseto characterize him in relational terms, but any father can also be consideredapart from the relation of paternity; for example, he can be described in termsof intrinsic features such as height, eye-colour, and DNA.With the help of thisdistinction, the problem of consistency can be resolved. Thus the soul hasno intrinsic states that are not obscure and confused sensations, but at leastsome of these states, considered in terms of their relations to ideas, are pureperceptions.

2 On the theory of efficacious ideas, see A. Robinet, Système et existence dans l’oeuvre deMalebranche (Paris: Vrin, 1965), pp. 259–62. See also chapter 3 in this volume.

3 M. Gueroult, Malebranche (Paris: Aubier, 1955–9), vol. 1, pp. 189–90.4 T. Schmaltz, Malebranche’s Theory of the Soul: A Cartesian Interpretation (New York:

Oxford University Press, 1996), pp. 102–3.



Although this interpretation effectively resolves the problem of consistency,it receives no direct support from the texts; moreover, it suggests that anymodification of the soul—no matter how obscure and confused—is capableof serving as a ground to a relation to ideas, and we may wonder whetherMalebranche would wish to assert this. It is, I think, natural to embrace analternative solution to the problem. When Malebranche says that the mindfinds in itself only obscure and confused sensations, he is considering its plightin abstraction from the contribution of God’s action in illuminating the soulwith divine ideas. Sensations are the only properties which the soul has inabstraction from this contribution. To say this, however, is not to say that pureperceptions are grounded in obscure and confused sensations. Perceptions areindeed relational properties, but when God illuminates the soul, these percep-tions, considered in terms of their intrinsic features, are not simply obscure andconfused sensations. It is a merit of this interpretation that it does justice toMalebranche’s metaphorical insistence that the human mind is an illuminatedlight, not an illuminating light. When a place that was in shadow comes to beilluminated by the sun’s rays, then it undergoes a change in its intrinsic and notjust its relational properties; it comes to be bright and sunny. However, to saythis is not to deny either that the sun’s illumination is a causal relation or thatthe same place, when considered apart from the sun’s contribution, is dark andgloomy.This interpretation stays closer to the text, but it raises philosophical diffi-

culties of its own. It poses the problem of whether Malebranche is entitled todistinguish in this way between sensation and pure perception in terms ofGod’s contribution. It is true that Malebranche appears to have the resourcesfor distinguishing between sensations and the perceptions of ideas in termsof their causal source; sensations arise in us by virtue of the laws of the union ofmind and body, whereas the perceptions of ideas arise in us by virtue of the lawsof the union of the soul with God (DMR XIII.9, OCM XII 319; JS 252–3).However, when Malebranche speaks of these psychophysical laws, he is dis-cussing matters at the level of occasional causality; states of the brain cannot begenuine causes of sensations, but only occasional causes. Thus, there is a sensein which even sensations have God as their genuine cause. Perhaps it will besaid, on Malebranche’s behalf, that though God is indeed causally responsiblefor producing sensations, the causal action in question does not consist inilluminating the soul. Thus, we can say that, apart from divine illumination, thesoul finds only obscure and confused sensations in itself while recognizing thatGod is their genuine cause. This is perfectly correct, but it is fair to note that inhis later writings Malebranche tends to minimize the distinction between theways in which sensations and perceptions are produced in the soul. He writes asif even sensations, no less than pure perceptions, are the result of the efficacy ofdivine ideas. Certainly the only difference between sensations and pure per-ceptions is in terms of how ideas touch or affect the soul (Conversations



chrétiennes III, OCM IV 75–6).5 Thus, on this view, very little is left of the soulwhen it is considered in abstraction from the contributionmade byGod’s ideas.It is not for nothing that the French scholar, Alquié, remarks that the soul, soconsidered, is no more than a pure potentiality.6

I I

Malebranche thus broke with the Cartesian doctrine of pure intellect. Notmerely is the human mind not stocked with innate ideas and beliefs, but it hasno active native faculty for attending to such objects of thought. As anilluminated light, the Malebranchian mind has a pure intellect at most in thevery minimal sense that it possesses a purely passive power of being affectedby the light of divine ideas. Malebranche further broke with Descartes in aphilosophically significant way in his theory of sensations; for Malebranche,sensations constitute a distinct class of mental states that have no object orcontent. The moral of this theory is the controversial anti-Cartesian thesis thatintentionality is not one of the marks of the mental. In this way, Malebranchestands aside from a tradition of thinking about the nature of the mental thatspans Descartes and Husserl.

Perhaps the best way of bringing out the originality and interest of Male-branche’s theory of sensations is by means of a notorious passage in theElucidations to The Search After Truth. On the strength of this passageMalebranche was ridiculed as a believer in the rainbow-coloured soul:

You even make a fool of yourself before certain Cartesians if you say that the soulactually becomes blue, red, or yellow, and that the soul is painted with the coloursof the rainbow when looking at it. There are many people who have doubts, andeven more who do not believe, that when we smell carrion the soul becomesformally rotten, and that the taste of sugar, or of pepper or salt, is somethingbelonging to the soul.

(SAT, Elucidation XI, OCM III 166; LO 634)

The idea that the soul becomes red in perceiving something red is not originalwith Malebranche; it has precedents in Aristotle’s own very different theory ofperception.7 However, despite, or perhaps because of its Aristotelian roots, it isnot difficult to see why the theory of the rainbow-coloured soul should haveencountered resistance. The theory does indeed sound odd to the ears; itsounds odd for the reason that ordinary language embodies the commonsense

5 This passage was added in a later edition. See also DMR V.5, OCM XII 116; JS 77.6 F. Alquié, Le Cartésianisme de Malebranche (Paris: Vrin, 1974), p. 105.7 TadSchmaltzhas shown thatMalebranche’s discussionof the rainbow-coloured soul has its roots

in a series of philosophical conferences at Commercy. SeeMalebranche’s Theory of the Soul, p. 82.



assumption that it is fire engines and pillar boxes, for example, that are red,not minds or souls. However, orthodox Cartesians would not be satisfied withthis objection from ordinary language, for they are committed to the view thatordinary language is a repository of philosophical mistakes. Moreover, even ifCartesians agree that colours are in some sense in physical objects themselves,they cannot concede that they are present in such objects in the way unre-flective common sense takes them to be; on the side of bodies they are simplydispositions to cause sensory ideas (sensations) in our minds by virtue of thesurface textures (Principles of Philosophy IV.198, AT IXB 322; CSM I 285).Nonetheless, although this objection is debarred to the Cartesians, it is stillpossible to see why they should have philosophical scruples about the doctrineof the rainbow-coloured soul. An orthodox Cartesian will insist that eventhough they are confused, sensations are still ideas, and that it is essential toideas as such to have objective reality, in technical jargon. In other words,ideas by their very nature have intentional content. Just how this intentionalcontent is to be specified is controversial, but on one interpretation it will be interms of the body’s primary qualities. To have a sensory idea of red is to havean obscure and confused representation of the surface texture of a red body. Itis just this feature of orthodox Cartesian teaching that Malebranche is con-cerned to deny. To have a sensation of red is not strictly to have a sensation ofanything—in this respect ordinary language is misleading—it is simply for thesoul to be in a certain sensory state. When I look at the setting sun, my soulmay more accurately be said to sense redly. Thus Malebranche is advocatingwhat we may call an adverbial theory of sensation.The claim that Malebranche advances an adverbial theory of sensation may

be viewed with some scepticism. It may be pointed out that Malebrancheregularly speaks of sensations in Cartesian language as obscure and confused.In the Dialogues on Metaphysics, for example, he says that there is alwaysa clear idea and confused sensation in the view we have of sensible objects(DMR V.1, OCM XII 113; JS 74). It is natural to object that such a character-ization of sensations makes sense only on the Cartesian assumption thatsensations, like ideas in general, have intentional content. For example, tosay that I have an obscure and confused idea of a right-angled triangle mightmean a number of things. It might mean that I am unable to perceive that thePythagorean theorem is true. Or it might mean that I am unable to discrimin-ate perceptually between a right-angled triangle and one that has an acuteangle of eighty-five degrees. However, in each case there is some intentionalobject or content of which I have an imperfect apprehension.It is always possible that in pioneering an adverbial theory of sensations

Malebranche retained relics of Cartesian habits of thought without seeingthat they had no place in his thinking. However, in fact, I believe that itis not difficult to see how appealing to the obscurity and confusion of sensa-tion might have a real point in Malebranche’s new theory. For one thing,



Malebranche may mean that sensations are characteristically accompanied byfalse judgements; when I have a sensation of red that is occasionally caused bya fire engine, I tend to judge falsely that there is something on the surface ofthe fire engine that corresponds to my sensation of red. Or Malebranche maymean that such sensations are cognitively empty; thus there is nothing in mysensation of red itself that enables me to infer to the nature of the surfacetexture of the particles of the body that we would pre-theoretically call red.Indeed, as Schmaltz has shown, there are not even strong correlations betweenparticular shades of colour and particular surface textures.8

Malebranche’s tendency to follow the orthodox Cartesians in saying thatsensations are confused is thus not evidence against his subscription to theadverbial theory. Nor need we suppose that such expressions are simplyunassimilated relics of the Cartesian thesis that sensations have intentionalcontent. However, it may be doubted how clearly Malebranche saw theimplications of holding an adverbial theory of sensation. Steven Nadler ob-serves that on occasion Malebranche speaks of sensing or perceiving ideas ascoloured, as red for example. He even writes as if ideas were like pictures on towhich sensations could be attached or projected like a painter’s colours (OCMVI 78). However, according to Nadler, such expressions betray an element ofconfusion in Malebranche’s thinking.9 Malebranchian ideas are properlyconstrued as logical concepts; they are, for example, geometrical concepts ofcircles and triangles. Now we might say (at least pre-theoretically) that a givencircular figure is red and blue, but logical concepts are not the sort of thingsthat can be perceived or sensed redly or bluely or on to which colour canbe projected.

There is no need to deny that Malebranche sometimes writes as if ideas arelike pictures on to which the mind can project colours. However, it is a mistaketo suppose that such expressions point to a real confusion in his thought. Onthe contrary, Malebranche may be availing himself of a convenient, if some-what misleading, shorthand expression. To say that ideas are sensed redly issimply a façon de parler. What Malebranche really means is expressed morecarefully in an important passage from The Search After Truth:

When we perceive something sensible two things are found in our perception:sensation and pure idea. The sensation is a modification of our soul, and it is Godwho causes it in us. He can cause this modification even though He does not haveit himself, because he sees in the idea he has of our soul that it is capable of it. Asfor the idea found in conjunction with the sensation, it is in God, and we see itbecause it pleases God to reveal it to us. God joins the sensation to the idea when

8 See Schmaltz, ‘Malebranche’s Cartesianism and Lockean Colors’, History of PhilosophyQuarterly 12 (1995), 387–403.

9 S. Nadler, Malebranche and Ideas (New York: Oxford University Press, 1992), pp. 64–5.



objects are present so that we may believe them to be present and that we mayhave all the feelings and passions that we should have in relation to them.

(SAT 3.2.6, OCM I 445; LO 234)

Thus to say that ideas are sensed redly is to say that a sensation of red occurs inconjunction with the perception of an idea (a geometrical concept) in such away that I take my experience to be of a red circular body, for example.Malebranche may have been led to adopt the formulation to which Nadlerrightly objects by a desire to do justice to the tight phenomenological connec-tion between two elements in my sensory experience that are really discreteand heterogeneous. It is this tight connection that is expressed in our pre-theoretical judgement that when I perceive a setting sun, I am perceiving abody that is both red and circular.Malebranche, then, advances an adverbial theory of sensation, but in one

way he may seem to be an adverbialist with a difference. Characteristically, themotivation for introducing adverbial theories is a desire to honour Ockham’srazor—the principle that entities are not to be multiplied unnecessarily. Suchphilosophers seek to avoid a commitment to dubious or suspect entities such assense-data. Instead of saying that in seeing a red patch I immediately perceivea red sense-datum, the adverbialist will insist that I am simply in a certainsensory state. By contrast, Malebranche offers a theory of sense-perception thatseems to proliferate with just the dubious entities that the adverbialist seeks toavoid. He insists that in every act of sense-perception, I am immediately relatedto extra-mental entities (ideas) whose locus is God. ThusMalebranche’s theoryof sensation can hardly be motivated by concerns of ontological economy.However, this objection may be mistaken, for it fails to take account of thestructure of Malebranche’s theory of sense-perception: it fails to recognize that,for Malebranche, every act of sense-perception involves an irreducibly intellec-tual element of judging or seeing that. According to Malebranche, we cannotgive a satisfactory account of this feature of sense-perception unless we recog-nize the mind’s relationship to extra-mental ideas whose locus is God. Male-branche can plausibly insist that his appeal to ideas involves no violation of theprinciple of Ockham’s razor, for it is not gratuitous. But matters are differentwhen what is at issue is the strictly sensory side of sense-perception. Here thereis no such philosophical pressure to postulate the existence of entities over andabove mental states. Malebranche can agree with the adverbialist that sense-data are dubious entities which we can, and should, do without. Malebranche’sbrand of adverbialism may be unfamiliar, but it is premature to suppose that itis not motivated by a desire to honour Ockham’s razor.Before we leaveMalebranche’s theory of sensation, let us note one interesting

implication of the theory for the status of animals. His theory has the resources,which he never developed, to offer a radical alternative to Descartes’ notoriousthesis that animals are mere machines or automata. Consider one way inwhich Malebranche’s theory of sensations departs from Cartesian orthodoxy.



According to Descartes, sensations are confused ideas ormodes of thinking thatarise from the mind’s union or, as it were, intermingling with the body (Medi-tationsVI, AT VII 81; CSM II 56). That is to say, they are intellectual states thathave become corrupted or polluted by being admixed with something extrane-ous to the mind. In terms of this theory, then, Descartes could not consistentlyascribe sensations to animals without also endowing them with a capacity, atleast in principle, for purely intellectual awareness. Understandably, Descartes isunwilling to grant animals such a capacity. Malebranche, by contrast, breaks withCartesian orthodoxy in his theory of sensation. In his theory, at least according toThe Search After Truth, sensation is wholly heterogeneous from perception,which is by its nature intellectual. Perception involves the mind’s relationship toideas, and ideas, as has been seen, are entities in God. Thus there can be noperception without divine illumination. Sensation, by contrast, is a non-inten-tional and non-relational state of the soul. Thus by virtue of his innovations in thisarea Malebranche has the resources to avoid the Cartesian doctrine of the beast-machine. Indeed, it seems that Malebranche is in a position to advance a ratherintriguing theory of animal consciousness. He could say that though animals haveno capacity for judgement, or seeing that, they do have the capacity to feelsensations such as pain and hunger. The cat, for example, cannot see that thereis a circular dish in front of her, but she can sense patches of colour. The mentallife of animals could be one of buzzing, blooming confusion. It is true that such atheory would ascribe a more minimal form of consciousness to animals than thatwhich most of us would be inclined to attribute, but at least it would do justice tothe profoundly anti-Cartesian intuition that animals feel pain and hunger.

Malebranche, in fact, does not exploit the resources of his theory in thisway; he continues to toe the party line of the beast-machine doctrine. Indeed,he states it perhaps even more dogmatically than Descartes himself does:

Thus in animals, there is neither intelligence nor souls as ordinarily meant. Theyeat without pleasure, cry without pain, grow without knowing it; they desirenothing, fear nothing, know nothing; and if they act in a manner that demon-strates intelligence, it is because God, having made them in order to preservethem, made their bodies in such a way that they mechanically avoid what iscapable of destroying them.

(SAT 6.2.7, OCM II 394; LO 494–5)

However, his reasons for toeing the party line have less to dowith the philosophy ofmind than with theological considerations. According toMalebranche, the ascrip-tion of sensations to animals is inconsistent with the principle that under a justGod the innocent will not suffer. It is important to see, then, that Malebranche’sloyalty to the party line owes little to pressures from the philosophy of mind.10

10 For a very different view of Malebranche’s reasons for holding that animals are meremachines or automata, see D. Radner and M. Radner, Animal Consciousness (Buffalo: Prome-theus Books, 1989), pp. 70–91. See chapter 4 in this volume.



I II

It is tempting to say that the main themes ofMalebranche’s philosophy of mindare encapsulated in two slogans: (1) the mind is not a light to itself, and (2) wehave no idea of the mind or soul. Malebranche sometimes runs these two claimsin tandem, but strictly speaking this is misleading, for they seem to be logicallyindependent. It is true of course that if the mind is not a light to itself, we cannothave a clear idea of the mind in a Cartesian sense; that is, the idea in questioncannot be a psychological possession with which we are, perhaps innately,endowed. However, from the fact that we are not a light to ourselves it doesnot follow that we are not capable of having epistemic access to God’s idea of themind. Conversely, from the fact that we have no idea of the mind, it does notfollow that we have no native resources of our own for attaining knowledge. Itmight be the case that though self-knowledge was debarred to us, we coulddiscover within ourselves the resources for a science of the physical world. Thusin focusing here in this section on the second ofMalebranche’s twomain themeswe shall be studying a new and distinct strand in his philosophy of mind.In his case for the negative thesis Malebranchemounts a powerful critique of

Descartes. This critique embodies the remarkable insight that there is a seriousmuddle at the heart of Descartes’whole theory of knowledge.Wemay bring outthe force of Malebranche’s point by appealing to Descartes’ famous appeal toclarity and distinctness as a criterion of truth. If we look for the paradigm casesof clear and distinct ideas in Descartes, it is natural to turn to geometry. Theidea of a right-angled triangle is clear and distinct in the sense that variousproperties are deducible from it. The Pythagorean theorem, for example, can bederived from the axioms, definitions, and postulates of Euclidean geometry. Onthis account, then, the role of clear and distinct ideas is to ground a prioriknowledge. However, Descartes also appeals to clear and distinct perception inorder to ground the certainty of his own existence, but here what is at issue issomething very different: the source of certainty in this case is simply theincorrigible and self-verifying nature of such a judgement as ‘I exist’. Descartes’whole conception of clear and distinct perception, as a criterion of truth, thusinvolves a conflation of two radically distinct kinds of knowledge: what Male-branche calls knowledge through ideas and knowledge through consciousnessor sensation (SAT, Elucidation XI, OCM III 167; LO 635). Knowledge of thesecond kind may indeed achieve the highest kind of certainty (as in the case ofthe cogito), but it is only knowledge of the first kind, knowledge through idea,that is capable of issuing in scientia—that is, a systematic body of demonstra-tive truths of the sort that was traditionally held to constitute science.Malebranche is well placed to distinguish these two kinds of knowledge by

his resolute anti-psychologism—that is, by his insistence on distinguishingbetween the provinces of logic and psychology. When Malebranche appeals to



knowledge through idea, he draws our attention to a kind of knowledge that isconversant about logical concepts whose locus is God. Although Malebranchesometimes speaks of ideas as if they were psychological items, we know thatthis is not his considered position. Knowledge through consciousness orsensation, by contrast, involves nothing that is not psychological. For Des-cartes, however, all knowledge is concerned with psychological items. He iscommitted to denying the existence of a Platonic third realm. Thus it is easierfor Descartes than it is for Malebranche to blur the distinction between theprovinces of a priori and incorrigible knowledge.

Malebranche’s key distinction between the two kinds of knowledge is atwork in his justified critique of one of Descartes’ defences of the claim thatwe know the nature of the mind better than the nature of body. In the FifthObjections Gassendi complains that Descartes has not succeeded in establish-ing this proposition (AT VII 275–6; CSM II 192–3). In reply, Descartesexplains how our knowledge of the nature of the mind necessarily outrunsour knowledge of the body’s nature; in knowing any property of a body, suchas the piece of wax, I necessarily know a corresponding property in my mind.By contrast, the converse is not true:

As for me, I have never thought that anything more is required to reveal asubstance than its various attributes; thus the more attributes of a given substancewe know, the more perfectly we understand its nature. Now we can distinguishmany different attributes in the wax: one, that it is white; two, that it is hard; three,that it can be melted; and so on. And there are correspondingly many attributes inthe mind: one, that it has the power of knowing the whiteness of the wax; two,that it has the power of knowing its hardness; three, that it has the power ofknowing that it can lose its hardness (i.e. melt), and so on. . . .The clear inferencefrom this is that we know many more attributes in the case of our mind than wedo in the case of anything else. For no matter how many attributes we recognizein any given thing, we can always list a corresponding number of attributes in themind which it has in virtue of knowing the attributes of the thing; and hence thenature of the mind is the one we know best of all.

(AT VII 359–60; CSM II 249)

Intuitively, Descartes’ defence of his position here is most unappealing. I maybe able to list more properties of my computer than of my pencil-sharpener,but it would hardly be convincing to say that I thereby know the nature of theformer better than the nature of the latter. In terms of his distinction betweentwo kinds of knowledge, Malebranche is able to suggest why even on his owngrounds Descartes is not entitled to this simple-minded kind of defence.Malebranche insists that the ability to enumerate properties in this wayinvolves knowledge by consciousness only: it does not amount to knowledgeby idea, that is, a priori knowledge (SAT, Elucidation XI, OCM III 167; LO635). Malebranche’s point is that Descartes is implicitly committed to agreeingthat knowing the nature of x requires or even consists in a priori knowledge.



On Cartesian principles geometry is clearly a paradigm case of a disciplinewhere we know the nature of the objects of study, and if we ask what suchknowledge involves, it seems obvious that it is the ability to derive theoremsfrom axioms, definitions, and postulates. Further, such knowledge is a prioriknowledge or knowledge through ideas in Malebranche’s terms.When Malebranche denies that we have a (clear) idea of the soul, it is a

priori knowledge that is in question; it is such knowledge as issues in scientia,as in geometry. Malebranche offers several arguments to show that we have,and can have, no such knowledge of our mind. In the first place, he arguesfrom our inability to know a priori the properties or modifications of whichthe mind is capable:

Surely we have no idea of our mind which is such that, by consulting it, we candiscover the modifications of which the mind is capable. If we had never feltpleasure or pain we could not know whether or not the soul could feel them. If aman had never eaten a melon, or seen red and blue, he would consult this allegedidea of his soul in vain and would never discover distinctly whether or not it wascapable of these sensations or modifications.


It is only through experience that we discover that the mind has a capacity forfeeling pain or sensing the taste of a melon. To borrow an example from Locke,when a person tastes a pineapple for the first time, he experiences a new kind ofsensation, and thus learns that he was capable of this experience (Essay III.iv.11). However, he could not discover a priori that his mind was endowed withsuch a capacity. As Malebranche points out, the situation is wholly different inthe case of geometry; we do not need to rely on experience to discover that asquare is capable of being divided into two right-angled triangles. We candeduce that it has this property from the axioms, definitions, and postulates ofEuclidean geometry.Malebranche offers a second, related argument for the thesis that we have

no idea of the mind from the status of sensible qualities. Unlike the first, thisargument does not turn on a denial that we are lacking in a priori knowledgeabout the mind in a certain area. Allowing that we can have some knowledgeof this kind, it turns rather on the denial that such knowledge proceeds fromthe idea of the mind (as opposed to the idea of extension). As we have seen,Malebranche rightly insists that experience is necessary to tell us what sensa-tions our mind is capable of; experience, however, leaves us wholly in the darkabout the ontological status of sensible qualities such as colour, taste, andodour. This is an issue that can be resolved a priori, but it can be resolved onlyby consulting the idea of extension:

In order to determine whether sensible qualities are modes of the mind, we do notconsult the alleged idea of the soul—the Cartesians themselves consult, rather, theidea of extension, and they reason as follows. Heat, pain, and colour cannot be



modifications of extension, for extension can have only various figures andmotion. Now there are only two kinds of beings, minds and bodies. Therefore,pain, heat, colour, and all other sensible qualities belong to the mind.


Malebranche’s aim here is to show how the reasoning of the Cartesians them-selves provides support for the premise that we cannot determine the status ofsensible qualities a priori by consulting the idea of the mind. Malebranche’sreasoning here seems to take the form of inference to the best explanation. TheCartesians take a roundabout way of arguing that sensible qualities are modes ofmind, and the best explanation for their taking this detour is that the directroute to this conclusion is blocked. In other words, they do not have epistemicaccess to an idea of the mind that would allow them to argue in a straightfor-ward way for the conclusion that sensible qualities are merely modes of mind.

In the Elucidations Malebranche offers a final argument that turns on theclaim that knowing the nature of a thing necessarily involves the ability todiscover its relations with other things of the same kind. However, in the caseof the mind’s modifications, no such comparison is possible. We cannotexpress relations between our sensations in the way that we can express therelations between numbers and between geometrical figures:

But we cannot compare our mind with other minds in order to discover clearlysome relation between them.We cannot even compare the modes of our mind, itsown perceptions. We cannot discover clearly the relation between pleasure andpain, heat and colour, or to speak only of modes of the same kind, we cannotexactly determine the relation between green and red, yellow and violet, or evenbetween violet and violet. We sense that the one is darker or more brilliant thanthe other, but we do not know clearly by how much or in what being darker ormore brilliant consists.


It may be objected that in the case of some sensible qualities, such as sounds, anordering of this kind is possible. A musician, for example, can determine that aparticular interval is an octave or a fifth. Malebranche effectively responds to thisobjection by arguing through a dilemma. Any such ordering is either bymeans ofphysical properties withwhich sounds are correlated or it is purely empirical, andhence, lacking in themathematical precision of the relation between vibrations.11

However, in neither case is there any parity with the kind of precise a prioriknowledge that is possible with regard to numbers and geometrical figures.12

11 For further discussion of Malebranche’s argument, see Schmaltz, Malebranche’s Theory ofthe Soul, p. 75.

12 Tad Schmaltz has observed (Malebranche’s Theory of the Soul, p. 75) that Malebranche hereanticipates Robert Adams who draws attention to the implausibility of supposing that there is aunique objectively valid spectrum in which all phenomenal qualia are ordered (see R.M. Adams,‘Flavors, Colors, and God’, The Virtue of Faith and Other Essays in Philosophical Theology



Malebranche’s case against the Cartesian thesis that the mind is betterknown than body is a powerful one, but it was subjected to a savage attack byArnauld. In this polemic Arnauld displayed his characteristic wit and dialect-ical skill. There is no doubt that he was an able proxy for Descartes himself, butit is fair to say that his attack left Malebranche’s thesis largely unscathed.Indeed, Arnauld never really succeeded in coming to grips with the heart ofMalebranche’s case, which is that we have no scientia with regard to the mind.

Perhaps Arnauld’s most telling point against his opponent is that in com-paring our knowledge of mind and body Malebranche tends to operate witha double standard.13 When Malebranche insists that we do not have a clearidea of the soul, he sets the epistemological bar high. The criterion he employsis that of knowledge par simple vue. In other words, to have a clear idea ofthe soul would be to have something like an intuitive knowledge of thoseproperties that derive from its essence. By contrast, when he argues that we dohave a clear idea of body, he lowers the bar considerably, so that even pre-Pythagoreans can jump over it despite their ignorance of the famous theorem.Obviously, such people do not satisfy the condition of intuitive knowledge ofthe properties that derive from the essence of geometrical figures. The point israther that in some sense they have a potential knowledge of such properties asthe one that is proved with respect to right-angled triangles in the case of thePythagorean theorem. Arnauld seems justified in claiming that Malebrancheequivocates in this way, but the equivocation is not seriously damaging toMalebranche’s case. For even if the epistemic bar is lowered in the case of theidea of the mind, it is still fair to say that we have no knowledge of the soul thatmeets this standard. That is, we have an a priori science of geometry, but wehave no a priori science of psychology. Arnauld never succeeds in graspingthis point or its importance.Arnauld is equally strident in his critique of Malebranche’s argument from

the ontological status of secondary qualities. Recall that, according to Male-branche, even the Cartesians are implicitly committed to holding that thestatus of such qualities can be determined only by appealing to the idea ofextension. Thus they are implicitly committed to holding that they do not havea clear idea of the soul. Arnauld responds by charging Malebranche with agross ignoratio elenchi here. It is silly to suppose that the Cartesians everargued in this way; indeed, no one has ever needed to appeal to the idea of

(Oxford: Oxford University Press, 1987), pp. 257–8). A relevant difference, however, is thatAdams is concerned to argue that such an ordering is in principle impossible, whereas Male-branche’s point is rather that it is contingently unavailable to us. God, by contrast, has access toan idea of the soul which presumably allows him to order these sensations in a way in which wecannot.

13 A. Arnauld, Des vraies et des fausses idées, Oeuvres de Messire Antoine Arnauld (Paris andLausanne: Sigismond D’Arnay, 1775–83; reprinted, Brussels: Culture et civilisation, 1964–67),vol. 38, ch. 23, pp. 321–2.



extension in order resolve the status of sensations of pain and colour, for noone has ever doubted that these are mind-dependent entities.14 But, in fact, forall the heat that he generates, it is Arnauld rather than Malebranche who isguilty of misrepresenting the issue. In his argument against the Cartesians,Malebranche speaks not of sensations but of sensible qualities, and he is surelyright to claim that the status of these qualities was a subject of controversybetween the Cartesians and their Scholastic opponents. The Cartesians mayhave disagreed as to whether sensible qualities are dispositional properties ofbodies or purely mind-dependent items, but they are at one in supposing thatthey are not straightforwardly categorical properties of bodies in the waycommon sense takes them to be, and that this fact about them needs to beestablished against the Scholastics by philosophical argument. Moreover, acase can be made for saying that Malebranche is accurate in his account of thestrategy of argument adopted by the Cartesians. They did appeal to the idea ofextension in order to determine that sensible qualities cannot be categoricalphysical properties.

How did Arnauld come to misread Malebranche in this way? The answermay well be that Malebranche’s list of the sensible qualities includes pain, andthat pain seems obviously and uncontroversially a mental item. In the spirit ofDescartes we might say that pain is nothing over and above a private sensa-tion. Philosophers who have absorbed Cartesian doctrine may well think inthese terms, but we should beware of supposing that this intuition is univer-sally shared. Some people seem to think of painfulness as a sensible quality inpretty much the Scholastic sense; with the rest of us they say that their armis painful when it is jabbed by a needle, but (unlike the Cartesians) they meanthat there is a straightforwardly physical property that is present in theaffected part of the body. Thus the inclusion of pain on Malebranche’s list ofsensible qualities may not be an oversight; even here there is an issue thatneeds to be resolved by philosophical argument.

Somewhat harder to assess is Arnauld’s objection to Malebranche’s claimthat our mental modifications cannot be ordered or compared. Arnauldcomplains that Malebranche is demanding the impossible here; he is unfairlyrequiring that sensations, which are essentially non-quantitative, stand inprecise quantitative relations.15 Sensations can of course differ among them-selves in terms of intensive magnitude: one shade of green is deeper or brighterthan another. However, it is merely silly (and confused) to complain that suchintensive magnitudes lack the precision of extensive magnitudes. Indeed, asRobert Adams observes, it was precisely the fact that sensations were not

14 Arnauld, Des vraies et des fausses idées, pp. 310–11.15 Arnauld, Des vraies et des fausses idées, pp. 314–15. See Schmaltz,Malebranche’s Theory of

the Soul, p. 76.



amenable to mathematical treatment that was one important motive forkicking the phenomenal qualia out of the physical world and into the mind.16

Once again Arnauld’s objection sounds initially impressive, but furtherreflection suggests some doubts about its adequacy. Indeed, it may be arguedthat this is a case where Arnauld leads with his chin. Arnauld may be implicitlyconceding that sensations are not candidates for scientia, that is, a systematicbody of knowledge. Rather, the only knowledge of which we are capable in thisarea is of the incorrigible kind, which Malebranche is prepared to concede.Perhaps it will be said that scientia is not necessarily quantitative, and thatsensations and the mind’s modifications are candidates for a scientia of thissort. However, then the onus of proof will be on Arnauld to show us what sucha kind of scientia would look like; here the presumption is very much inMalebranche’s favour that no such scientia is available.Malebranche’s critique of Descartes’ account of self-knowledge is powerful,

perhaps even unassailable. Certainly, there are good grounds for thinking thatMalebranche’s critique compares favourably with Gassendi’s otherwise similarcritique of Descartes on the score of self-knowledge. Gassendi complains thatDescartes has not succeeded in discovering the nature of the mind because hehas not revealed its internal substance or constitution. Gassendi famouslyinsists that a kind of chemical labour is needed to reveal this internal substance(Fifth Objections, AT VII 276–7; CSM II 193). However, Descartes dismissesthis criticism as misguided on the ground that it is of the essence of the mentalto have no internal constitution; there is no analogy with body in this respect.Malebranche, by contrast, is not vulnerable to this kind of response; in sayingthat we have no idea of the mind, the contrast that he invokes is not with ourability to know the internal structure of bodies but rather with our ability tohave an a priori science of geometry. Descartes could not without embarrass-ment dismiss Malebranche’s point by saying that it is of the essence of mind tobe resistant to a priori knowledge, for to concede this point would be tanta-mount to admitting the impossibility of a scientia of the mind.At the heart of the debate between Malebranche and the Cartesians is thus

the possibility of systematic a priori knowledge of the mind. This interpret-ation of the debate is seemingly challenged by Schmaltz who holds that the keycontrast is not between the a priori and the a posteriori but rather between theobjective and the subjective view.17 On this account Malebranche’s centralpoint is that whereas we have an objective view of bodies, we have only asubjective view of mental states. Now in one way the two approaches toMalebranche are on a par. Any commentator must take account of the fact

16 Adams, ‘Flavors, Colors, and God’, p. 258.17 Schmaltz, Malebranche’s Theory of the Soul, ch. 1, pp. 41–3. Perhaps Schmaltz is in danger

of conflating the thesis that mental phenomena are subjective with the very different thesis thatin the case of such subjective phenomena no objective knowledge is possible.



that, for Malebranche, there is an idea of the human mind to which God alonehas epistemic access. By virtue of this idea God has a priori knowledgeof mental states, and he also has an objective knowledge of them withoutof course experiencing them. Thus no discrimination between the two ap-proaches is possible in these terms. However, if we consider Malebranche’spolemical target, there are grounds for preferring the approach that stressesthe centrality of the issue of a priori knowledge. To insist on the subjectivity ofmental states is to insist on something that Descartes himself concedes; toinsist on our lack of a priori knowledge in this area is rather to insist onsomething that is controversial and damaging to the Cartesian project.

IV

On one set of issues Arnauld was able to throw down a pointed challenge toMalebranche. Malebranche claims to be able to demonstrate the freedom, spir-ituality, and immortality of the soul, yet it is difficult see how this is possible if wehave no clear idea of its nature. Indeed, Arnauld argues that it is in fact acontradiction to hold that we have no clear idea of the soul and that we cannonetheless demonstrate its properties. As a self-styled Cartesian philosopherMalebranche needs to tread carefully through this theological minefield. It mightseem that the safest, or at leastmost consistent coursewould be to adopt afideisticposition; he could take the line that the immortality of the soul, for instance, is atruth of faith for which no rational justification is possible. YetMalebranche doesnot avail himself of this option. In what follows we shall take up the question ofwhether Malebranche can justify his confidence in the possibility of demonstrat-ing the spirituality and immortality of the soul. Malebranche’s attempts atdemonstration might not be convincing, but at least his strategy is instructive.

The issue of strategy is obviously crucial for Malebranche, because asArnauld sharply observes, he debars himself the obvious recourse of basinga proof on the idea of the mind. Yet to say this is not to say that he has nophilosophical resources for demonstrating properties of the soul. The directroute via the idea of the mind may be blocked, but it remains open to him toappeal to inner consciousness or to the idea of extension. As we have seen,Malebranche holds that an appeal to the idea of extension is necessary todetermine the ontological status of sensible qualities.

It is to the deliverances of inner consciousness that Malebranche appeals inThe Search After Truth:

Although our knowledge of our soul is not complete, what we do know of itthrough consciousness or inner sensation is enough to demonstrate its immortality,spirituality, freedom, and several other attributes we need to know. And this seemsto be why God does not cause us to know the soul, as he causes us to know bodies,



through its idea. The knowledge that we have of our soul through consciousness isimperfect, granted; but it is not false.

(SAT 3.2.7, OCM I 453; LO 239)

Malebranche here appeals to the Cartesian principle that we have incorrigibleknowledge of ourmental states; thus if I believe that I am in pain, for example, thenit is true that I am in pain.However, it is a far cry fromasserting such incorrigibilityto demonstrating the spirituality and immortality of the mind. As we shall see,Malebranche became dissatisfied with the strategy of appealing to inner con-sciousness, and this is hardly surprising, because it raises a number of difficulties.In the first place, the difficulty of proving that the mind is a spiritual

substance on his principles is complicated by the issue of his commitment toPlatonism. For Malebranche, the spirituality that he seeks to prove with regardto the soul cannot be simply equated with the property of being immaterial.Ideas in God are immaterial—they are not at all like tables and chairs—but theyare not spiritual in the sense in which the soul is supposed to be a spiritualsubstance; that is, they are not purely thinking or conscious beings. Perhaps it ispossible to mount a defence of Malebranche’s position here which would takesomething like the following form. Anything that is immaterial is either an ideaor it is spiritual. Now when I turn my consciousness on itself, I discover notmerely that the object of such consciousness is immaterial but also that it is notan idea, for I find that it does not have the properties of infinity, necessity, andthe like which can be predicated of all ideas. Nonetheless, although it is possibleto see how Malebranche might defend his position, it is fair to say that he doesnot adequately attend to the issue of the relationship between the properties ofbeing immaterial and spiritual. In the context of the mind–body problemMalebranche tends to write like an orthodox Cartesian who recognizes onlytwo kinds of substance and ignores the complicating factors introduced by hiscommitment to a kind of Christian Platonism.The fact that Malebranche often approaches the mind–body problem in the

spirit of Cartesian orthodoxy points to a more specific difficulty with his proofthat the soul is spiritual. As Schmaltz has argued, Malebranche may haveinherited some of Descartes’ difficulties in this area.18 Having established inthe Second Meditation the certainty of his own existence, Descartes proceedsto argue that he is a thinking thing. Unfortunately, as critics since Gassendihave observed, Descartes seems guilty of a damaging slide here; he seems tomove illicitly from ‘I am only certain that I am a thinking thing’ to ‘I amcertain that I am only a thinking thing’ (that is, a thing whose whole essenceconsists in thinking) (Fifth Objections, AT VII 276; CSM II 192).19 It seems

18 See Schmaltz, Malebranche’s Theory of the Soul, ch. 4.19 The offending passage is Meditations II, AT VII 27; CSM II 18. See also Descartes’

explanation at AT IXA 215–16; CSM II 276–7.



that in some of his formulations Malebranche may have been guilty of ananalogous mistake, expressed in terms of the deliverances of consciousness orinner sensation. That is, he may have moved from the weak thesis that innerconsciousness acquaints him with the fact that he is a thinking thing to thestronger thesis that inner consciousness acquaints him with the fact that he isonly a thinking thing.

A further difficulty is suggested by Malebranche’s claim that our knowledgeof the soul is imperfect or incomplete; he invites us to think of self-knowledgein terms of a model to which he is not entitled. Consider the case of a schoolboywho knows just enough Euclidean geometry to be able to demonstrate thePythagorean theorem; however, he does not know enough to be able todemonstrate more difficult theorems. By saying that our knowledge of it isincomplete Malebranche leads us to suppose that our epistemic position withregard to our soul is rather similar to that of the schoolboy geometer. We knowjust enough of its nature through inner consciousness to demonstrate itsspirituality and the like, even though there are a priori truths about the soulthat are hidden from us. However, this overlooks the fact that the distinctionbetween knowledge by idea and knowledge by consciousness or inner sensationis officially supposed to be a difference of kind, not a difference of degree only.Our knowledge by consciousness may allow us to make incorrigible judge-ments about our occurrent mental states, but there is no reason to suppose thatthis kind of knowledge can allow us to demonstrate truths about its nature oressence. The demonstration of such truths belongs to the sphere of knowledgethrough idea, or a priori knowledge, and it is Malebranche’s official positionthat such knowledge of the soul is debarred to us.

Whether and how far Malebranche was conscious of these difficulties is notentirely clear. Schmaltz has suggested that Malebranche may have been moreimpressed by another difficulty with his appeal to consciousness or innersensation; Malebranche may have been struck by the implausibility of main-taining that inner consciousness can establish the spirituality and immortalityof the mind while denying that it can resolve the problem of the ontologicalstatus of sensible qualities. In any case, whatever his reasons for dissatisfaction,Malebranche came to abandon the strategy of appealing to inner sensation orconsciousness. In 1693 Malebranche writes to Regis that the soul

senses only that it is, and it is evident that it can sense only what it is in itself. Itsees itself and knows itself if you will, but exclusively through inner sensation, aconfused sensation that discovers to it neither what it is nor what is the nature ofany of its modalities. This sensation does not reveal to it that it is not extended,still less that colour, that the whiteness, for example, that it sees in this paper, isreally only a modification of its own substance. This substance is thus onlyshadowy (tenebres) in this regard.

(OCM XVII-1 298)



Instead Malebranche adopts the only remaining strategy available to him. Hehas recourse to the idea of extension in order to prove the spirituality andimmortality of the mind.Malebranche offers somewhat different versions of the argument in differ-

ent places, but one version takes the following form:

(1) Thoughts are not relations of distance.(2) Anything which is not a relation of distance is not a modification of

extension.(3) Therefore, thoughts are not modifications of extension. (DMR I, OCM

XII 32–3; JS 7)

This argument seems vulnerable to several objections. In a brilliant short workcalled ‘Conversation of Philarète and Ariste’, which is a continuation ofMalebranche’s Dialogues on Metaphysics, Leibniz observes that a reductivematerialist would challenge the first premise:

[Malebranche’s spokesman] holds that no thoughts are relations of distance,because we cannot measure thoughts. But a follower of Epicurus will say that thisis due to our lack of proper knowledge of them, and that if we knew the corpusclesthat form thought and the motions that are necessary for this, we would see thatthoughts are measurable and are the workings of some subtle machines.

(G VI 587; L 623)

It is only fair to observe, however, that Leibniz is using one of his speakers toplay devil’s advocate here. Leibniz may have sought to criticize the argumentfrom the standpoint of the reductive materialist but he has no intention ofdefending such a position himself.In a more Lockean spirit it is also natural to observe that, even if sound, the

argument establishes less than the Cartesians suppose. With the CartesiansMalebranche is of course committed to identifying extension with the essenceof matter; thus the conclusion of his argument is really a subconclusionfrom which it is supposed to follow straightforwardly that thought is not amodification of matter. However, it is just this last step in the argument that ischallenged by Locke and others who reject the Cartesian doctrine that theessence of matter is extension. Thus, even if thought is clearly not a way ofbeing extended, it does not follow that it is not a modification of matter. In theEssay Concerning Human Understanding Locke further breaks with the Car-tesian framework by challenging the principle that any property of a substancemust be a determinate modification of its essence. He argues that, for all weknow, thought may be a property which is superadded by God to certainmaterial substances (Essay IV.iii.6).Malebranche also appeals ultimately to the idea of extension to prove the

immortality of the soul. Employing a strategy of proof which goes back toPlato’s PhaedoMalebranche argues that ‘if the mind is not extended, it will not



be divisible, and if it is not divisible, it must be agreed that in this sense it willnot be corruptible’ (SAT 4.2.4, OCM II 24; LO 274); thus the immortality ofthe soul is supposed to follow from its spirituality. The argument is parasiticon the prior proof of the mind’s spirituality, and as we have seen, Malebranchecame to believe that such a proof is dependent on an appeal to the idea ofextension. The idea of extension plays a similarly indirect role in a secondproof, which turns on general considerations concerning the indestructibilityof substances (OCM VI 163). Lacking a clear idea of a thinking substance, wemust turn to the idea of extended substance to furnish us with a model of whatis involved in being a substance. When we consult such an idea, we aresupposed to see that it is of the very nature of substance to be indestructible.It is natural to object of course that even if extended substance is necessarilyindestructible, it does not follow that it is indestructible by virtue of being asubstance. Hence the idea of extended substance offers no basis for provingthe immortality of the soul. However, Malebranche has a response to this.Extended substance is not indestructible by virtue of being extended becausethere are extended items—particular bodies, for example—which can bedestroyed; Malebranche need not deny that the human body is corruptedand destroyed at death. It is thus supposed to follow that extended substance isindestructible precisely as substance.

Malebranche, then, has a strategy for proving the spirituality and immor-tality of the mind that provides an answer to Arnauld’s challenge. This strategyremains at least formally consistent with his thesis that we have no idea of themind. No one today is likely to find these proofs impressive, but theirweaknesses should not blind us to the real strengths of Malebranche’s anti-Cartesian position on the idea of the mind. As Malebranche sees, surelycorrectly, it is the pursuit of scientia that really animates the Cartesian projectof first philosophy. It is this project that Descartes announces on the first pageof theMeditations when he says that his aim is to establish the sciences on newand secure foundations. Descartes could not admit that no scientia of the mindis possible without thereby conceding that, with respect to the highest kind ofknowledge, it is simply false that mind is better known than body. Further, tomake such an admission would surely be an embarrassment.20

Malebranche’s critique of Descartes on the issue of self-knowledge alsosuggests a different moral. Although he may never make the point explicitly,Malebranche seems to see that Descartes’ philosophy is really driven by a newconception of matter. Matter not only offers the paradigm of the intelligible; italso gives rise to a new conception of the mental. Descartes subscribes to whatmight be called a dustbin theory of the mind. The items that Descartes throwsinto this dustbin are whatever is left over from the picture of the world once

20 For further discussion of this issue see chapter 1 in this volume.



matter is defined in purely geometrical terms. Modern philosophers whoare highly critical of Descartes’ dualism have nonetheless often inherited itsaccount of the sphere of the mental, while failing to see how this account isshaped by a new conception of the material world. Malebranche was one of thefew philosophers to recognize that any serious challenge to Descartes’ phil-osophy of mind must also understand its roots in his philosophy of matter.



6

Occasionalism and Efficacious Lawsin Malebranche

According to Malebranche’s occasionalism, God is the one true cause; asMalebranche himself says in places, perhaps overdramatically, it is God whodoes everything (SAT, Elucidation XV, OCM III 213; LO 662).1 However, thereis surprisingly little agreement over how such a claim should be interpreted. It isclear thatMalebranche is committed to ruling out any division of genuine causallabour between God and created substances; it is less clear how much causalactivity is required on the part of the deity, and what form it takes. Indeed, theproper interpretation of Malebranche’s occasionalism has been debated eversince his own time. Thus, when Leibniz charged that Malebranche’s Godintervenes in the course of nature and resorts to perpetual miracles,2 Arnaulddisagreed sharply with Leibniz’s characterization. ‘Those whomaintain that mywill is the occasional cause of the movement of my arm’, he wrote,

do not claim that God does this in time by a new act of will each time that I will toraise my arm, but by that single act of the eternal will by which he has willed to doeverything which he has foreseen it will be necessary to do, in order that theuniverse might be such as he had decided it ought to be.

(4 March 1687, G II 84)

Arnauld may have been no friend to occasionalism or to Malebranche’sphilosophy in general, but he did feel the need to defend it against what heregarded as a case of misrepresentation.

On philosophical grounds it seems clear that there are reasons for prefer-ring what we might call a ‘minimalist’ reading of occasionalism in the spirit of

1 I am grateful to David Cunning, Tad Schmaltz, Zoltan Szabo, and Andrew Youpa fordiscussion of the issues, and to Marc Hight for helpful comments on a previous draft.

2 See Leibniz to Arnauld, 14 July 1686, G II 57–8. For other characteristic statements, see NewSystem of the Nature and Communication of Substances, paras. 12–13, G IV 483–4; AG 143;Essays in Theodicy, para. 61, G VI 136; H 156–7. For a partial defence of Leibniz’s critique ofoccasionalism, see Donald Rutherford, ‘Nature, Laws, and Miracles: The Roots of Leibniz’sCritique of Occasionalism’; S. Nadler (ed.), Causation in Early Modern Philosophy (UniversityPark: Pennsylvania State University Press, 1993), pp. 135–58; see also chapter 9 in this volume.


Arnauld; that is, if we abstract from the Christian miracles, God’s role islimited to willing the initial conditions of the universe and the laws of nature.On this interpretation, occasionalism is a simple and elegant philosophicaltheory that is far removed from the doctrine, attributed by Leibniz to Male-branche, according to which the occasionalist God is a busybody God. In thefirst part of this essay, I argue that the minimalist interpretation is not onlyphilosophically superior to its rivals; it is also better supported by the textualevidence, since it is required by Malebranche’s claim that laws are efficacious.In the second part of the essay, I address the problem of reconciling Male-branche’s doctrine of efficacious laws with his occasionalist thesis that nothingcreated is causally active. I argue that, despite appearances to the contrary, thedoctrine of efficacious laws is consistent with the thesis that laws are divinevolitions, and are thus not ontologically distinct from God himself.

I

The central problem in interpreting Malebranche’s account of divine causalityarises from his repeated claim that God acts by general volitions. Malebrancheexplains to Arnauld that, for him, to act by general volitions is the same thingas acting according to general laws (Réponse aux Réflexions, OCM VIII 651),but this explanation is perhaps not very enlightening. Steven Nadler hasargued that to say that God acts by general volitions or according to generallaws is simply to say that God’s ways are not chaotic and ad hoc, but regularand orderly.3 As Nadler points out, such a claim plays a central role inMalebranche’s whole project of theodicy, that is, the project of reconcilingthe justice of God with the various kinds of evil in the world.4 Absolutelyspeaking, God could intervene to prevent an evil such as a tile’s falling on aperson’s head, but such an intervention would be inconsistent with the laws ofphysics that God has established, and God’s preference for a world governedby simple, fertile laws is required in order for his work to honour him. But,according to Nadler, the claim that God acts by general volitions or accordingto general laws is not intended to offer a complete account of divine causality.On this view, Malebranche’s occasionalism still requires that God implementor execute the laws for the universe that he has established through his generalvolitions; that is, he must ensure, through an infinite series of individual

3 S. Nadler, ‘Occasionalism and General Will in Malebranche’, Journal of the History ofPhilosophy 31 (1993), 31–47, esp. 42. For some criticism of Nadler’s thesis see D. Clarke,‘Malebranche and Occasionalism: A Reply to Steven Nadler’, Journal of the History of Philosophy33 (1995), 499–504.

4 Nadler, ‘Occasionalism and General Will in Malebranche’, pp. 35–7.


Occasionalism and Efficacious Laws in Malebranche 93

volitions, that bodies and created minds behave in conformity to those laws.Thus, on this view, the laws of nature that he has established become no morethan a series of notes to himself, or aides-mémoire, on how he will act. Accordingto Nadler, then, God is doubly involved in the management of the universe: notmerely must he will the laws but he must implement or execute the laws that hehas established through his will. In the words of Nadler, God’s activity is‘constant and ubiquitous’; Malebranche’s God is ‘personally, directly, and imme-diately responsible for bringing about effects and causal changes in nature’.5

This reading seems open to a straightforward refutation; it is in conflict withMalebranche’s repeated claim that the laws of nature are efficacious. Such aview is expressed most prominently perhaps in The Search After Truth:

All natural forces are therefore nothing but the will of God which is alwaysefficacious. God created the world because He willed it: ‘Dixit, & facta sunt’ [Ps.32:9]; and He moves all things, and thus produces all the effects that we seehappening, because He also willed certain laws according to which motion iscommunicated upon the collision of bodies; and because these laws are effica-cious, they act, whereas bodies cannot act.

(SAT 6.2.3, OCM II 314; LO 449)

The view is further expressed even in texts that Nadler cites in support of hismore Leibnizian reading:

A body in motion is not at all a true cause [of the motion which it communicates].It is not a natural cause in the sense of the philosophy of the pagans; it isabsolutely only an occasional cause which determines by the collision (choc)the efficacy of the general law according to which a general cause must act . . .

(Méditations chrétiennes, OCM X 54)

And again, in the First Elucidation of the Treatise of Nature and Grace,Malebranche speaks of the general and efficacious laws of the union of souland body and of the communication of motions (OCM V 147). Now as thepassage from The Search indicates, to say that the laws of nature are efficaciousis to say that they (in conjunction with the initial conditions) are sufficient tobring about particular events in the world. In that case, there is no need foranother series of individual volitions by means of which God ensures conform-ity to the laws he has established. And if there is no need for such a series, Godwill not engage in such pointless volitional activity, for as Malebranche says inElucidation XV to The Search After Truth, ‘God does not multiply his volitionswithout reason: He always acts in the simplest ways’ (OCM III 215; LO 663).6

The evidence of the doctrine of efficacious laws is, in my view, decisive. Butit is only fair to examine the considerations that Nadler advances in favour of

5 Nadler, ‘Occasionalism and General Will in Malebranche’, pp. 31, 32.6 For a similar line of criticism, see A. Black, ‘Malebranche’s Theodicy’, Journal of the History

of Philosophy 35 (1997), 40.



his thesis. One source of evidence on which Nadler draws is the lengthyexchange between Malebranche and Arnauld. This exchange is indeed im-portant for our purposes, for as has already been suggested, Arnauld inter-preted Malebranche in precisely the way I believe to be correct; that is,in Arnauld’s view, Malebranche holds that general volitions are efficacious,and that there is thus no need for further acts of individual volition. To thisdoctrine Arnauld had objected on the ground that it undermines God’spaternal care for his creatures.7 Now, if Malebranche indeed believed thatindividual acts of volition were needed to execute the laws, it is here, in hisreply to Arnauld, that we should expect him to say so; Arnauld’s polemicsurely offered the ideal opportunity for correcting misapprehension about histrue position. In response to Arnauld, Malebranche does indeed speak of Godas having further volitions over and above his general ones; he is evenprepared to speak of these volitions as particular.8 But what is striking isthat these further volitions are not the individual volitions envisaged byNadler; they have nothing to do with the execution of the laws of nature:

When a thorn pricks me, God makes me feel pain as a consequence of the generallaws of the union of soul and body, according to which he acts in us incessantly. Itis not at all that God acts inme by a particular volition. I mean that if the thorn hadnot pricked me, God would not have made me feel the pain of the prick. I do notclaim that God has no particular volitions at all with regard to this pain whichI suffer; but [claim] only that it is not at all the effect of a particular volition in this.To have particular volitions is not in God the same thing as acting by particularvolitions, or having effective (pratiques) particular volitions. God wills in particu-lar that I perform a certain act of charity. But he does not will to act in me to makeme do it. God wills in particular everything which is in conformity with Order,everything which perfects his work. But God does not always do it, because thesame Order requires that he follows the general laws which he has prescribed tohimself so that his conduct may bear the mark of his attributes.

(OCM VIII 651)

In this remarkable passage Malebranche is expounding one of the familiarthemes of his theodicy. As a result of the general laws of soul–body union, itmay happen that on a particular occasion I fail to perform an act of charitythat God wishes me to perform; the laws of soul–body union have conse-quences that are in a sense in conflict with God’s particular volitions. But nocontradiction is involved, for according to Malebranche’s theodicy, generallaws take priority over particular volitions; God wills me to perform acts of

7 Arnauld, Réflexions philosophiques et théologiques sur le nouveau système de la nature et dela grace, Oeuvres de Messire Arnauld (Paris and Lausanne: Sigismond D’Arnay, 1775–83; repr.Brussels: Culture et civilisation, 1964–67), vol. 39, pp. 174–5.

8 It should be noted that Malebranche’s most characteristic definition of a miracle is that it isan event brought about by one of God’s particular volitions; see Réponse au livre des Réflexions, I,OCM VIII 696.



charity provided such acts are consistent with the laws he has established.Thus, strangely perhaps, there are occasions when God’s particular volitionsremain without effect. Whatever we may think of the theological adequacy ofsuch a doctrine, one thing is clear: Malebranche is not expounding the thesisthat of course general laws need to be executed by particular acts of volition.

The exchange with Arnauld thus fails to supply evidence of Malebranche’sexplicit commitment to a doctrine of the need for individual volitions toexecute the general laws. Nadler seems to hold, however, that Malebrancheis at least implicitly committed to recognizing the need for such further acts ofindividual volition; in particular, he is impressed by those passages whereMalebranche speaks of God as acting as a consequence of the laws that he hasestablished. According to Nadler, certain passages, such as the following,supply at least indirect evidence of Malebranche’s commitment to the needfor individual acts of volition over and above the general laws:

Now it is clear that God does not at all act by particular volitions in the sense thatI have often explained where he acts by general laws. When a thorn pricks me,God makes me feel pain as a consequence of the general laws of the union of mindand body according to which he ceaselessly acts in us.

(OCM VIII 651)

The same expressions are used in the First Elucidation of the Treatise ofNature and Grace:

I say that God acts by general volitions when He acts as a consequence of thegeneral laws that He has established. For example, I say that God acts in me bygeneral volitions when He makes me feel pain at the time that one pricks me;because as a consequence (en consequence de) of the general and efficacious lawsof the union of mind and body which He has established, he makes me suffer painwhen my body is ill disposed.

(OCM V 147)9

Nadler takes Malebranche to be saying that when God makes me feel pain, he issimply acting in accordance with the laws of soul–body union: God looks to thelaws he has established as a guide or manual, and then gives me the appropriatesensations by a particular volition. But Malebranche’s meaning, I submit, isquite different. To say that God acts as a consequence of general laws is not tosay that God looks to these laws as a guide; it is rather to say that God acts byvirtue of the laws he has established. What Malebranche is doing is to clarify thenature of divine causality; it is precisely by willing the laws of nature, plus theinitial conditions, that God brings about events in the world. The consequence

9 Significantly, Nadler mistranslates the phrase ‘en consequence des loix generales et efficaces’as ‘in accordance with the general and efficacious laws’, Nadler, ‘Occasionalism and General Willin Malebranche’, p. 43; cf. D. Cunning, ‘Systematic Divergences in Malebranche and Cudworth’,Journal of the History of Philosophy 41 (2003), 343–63.



in question is logical rather than the quasi-causal one that Nadler finds in thetext; that is, from a statement of the initial conditions, plus the laws of soul–bodyunion, it follows logically that I shall have a sensation of pain on a particularoccasion when my flesh is pricked by a thorn. Now in the case of human agencyone might be inclined to doubt whether the agent is really committed to willingsuch a particular act; because of imperfect knowledge the agent might besurprised by the consequences of the general rule and the antecedent conditions.But in the case of God, who is omniscient, such a scruple is removed: God reallywills all the particular consequences of his general volitions.One objection that Nadler raises against the present ‘minimalist’ interpret-

ation is likely to occur to many readers; it concerns Malebranche’s subscrip-tion to the doctrine that God conserves the world by continuously creating it.This is not just a doctrine to which Malebranche subscribes as a good Carte-sian; it forms the basis for one of his chief and most interesting arguments foroccasionalism. According to Nadler, the doctrine makes the need for discretevolitional acts on the part of God ‘especially clear’:10

At every moment, God must re-create the universe in order to maintain it inexistence. Now this continuous creation of the universe involves a continuous re-creation of every object therein. Hence, God must constantly will that our billiardball exist; otherwise it would cease to exist.11

Perhaps the first thing to be said is that the issue of time is in many ways a redherring in this debate. According to Nadler, at every moment Malebranche’sGod constantly re-creates the universe, and though Malebranche may occa-sionally write in these terms, it is common ground that this is a loose way ofspeaking; as Nadler himself concedes, Malebranche’s God is outside timealtogether.12 God indeed may eternally will in respect of events in time; hemay have temporally indexed volitions to the effect that a body b be in place pat time t. But to say this is not of course to say that his volitions, whethergeneral or particular, are events that take place in time. Thus any discussion ofthe continuous creation doctrine and its implications for occasionalism mustrecognize the strict atemporality of the divine volitions. The real issue, then, isnot whether God wills in time, but whether the doctrine of continuouscreation implies that, to sustain the universe, God must eternally have a seriesof discrete, individual, and temporally indexed volitions.One way of responding to this objection would be to question Male-

branche’s commitment to the doctrine of continuous creation. As we haveseen, the chief role played by the doctrine in Malebranche’s thought is as a keypremise in the argument for occasionalism. According to Malebranche, when

10 Nadler, ‘Occasionalism and General Will in Malebranche’, p. 42.11 Nadler, ‘Occasionalism and General Will in Malebranche’, p. 42.12 Nadler, ‘Occasionalism and General Will in Malebranche’, p. 44.



the doctrine is properly interpreted, it will be seen that it leaves no room for arealm of secondary causes.13 For in conserving or re-creating bodies, forexample, God does not simply will that they be in some place or other andthen leave it up to bodies themselves to determine their specific states inaccordance with the laws of physics; rather, God’s volitions are fully specificwith regard to such things as the location and velocity of bodies. Thus thedoctrine of continuous creation enables Malebranche to argue that evenorthodox Cartesians, who of course accept this doctrine, are implicitly com-mitted to occasionalism. It might be wondered, then, whether the doctrine ofcontinuous creation forms the basis for an argument against the Cartesiansthat is merely ad hominem; on this view, even if the doctrine of continuouscreation does imply a commitment to discrete acts of divine volition, we couldnot thence infer that Malebranche was committed to recognizing such voli-tions. The suggestion is intriguing, but there is no direct evidence that theargument is intended to be merely ad hominem.Fortunately, amore promising strategy is available; it consists in showing that

the doctrine of continuous creation can be reductively analysed in terms ofGod’s efficacious general volitions. Such a strategy gains plausibility when weconsider the point of the doctrine of continuous creation; as Malebranche’sspokesman emphasizes, the doctrine does justice to the essential dependence ofcreatures in God in all their states (DMR VII.8, OCM XII 157; JS 113). Nowother philosophers had emphasized that the doctrine of continuous creationimplies that creatures depend on God as a causally necessary condition of theirstates; in other words, they had conceived ofGod’s continuous creation as a kindof background condition, like the presence of oxygen in the air.Malebranche, bycontrast, goes further: creatures depend on God as a causally sufficient condi-tion of all their states. Aswe have seen,God does not simplywill that a particularbilliard ball continue to exist in some way or other; he is causally responsible forall its determinate properties, such as its particular location and velocity. It iseasy to see how a reductive analysis can accommodate such a claim. To say thatall of the billiard ball’s states depend on God as a causally sufficient condition isto say they can all be genuinely explained in terms ofGod’s general volitions (thelaws of physics) and the initial conditions which he wills.14 The doctrine ofcontinuous creation is thus very far from requiring discrete particular volitionscorresponding to each state of a creature.15

13 Malebranche’s fullest statement of the argument for occasionalism from the continuouscreation doctrine is found in Dialogues on Metaphysics and Religion VII.

14 In the Dialogues on Metaphysics (VII.10) Malebranche even says that the conservation ofcreatures is ‘simply a continuous creation, a single volition subsisting and operating continu-ously’ (OCM XII 160; JS 115).

15 It might be thought that Nadler’s interpretation is required if Malebranche is to be able todo justice to the theologically orthodox doctrine that God has a providential care for hiscreatures. However, Andrew Black has shown how this doctrine can be accommodated by an



II

Malebranche’s doctrine of efficacious laws thus seems to be decisive evidenceagainst the thesis that God needs to execute the laws by discrete individual actsof volition. But the doctrine of efficacious laws raises its own problems ofinterpretation, for it may seem to be inconsistent with the central tenet ofoccasionalism, namely, that God is the one true cause. Recall that, according toMalebranche, ‘God . . .willed certain laws according to which motion is com-municated upon the collision of bodies; and because these laws are efficacious,they act whereas bodies cannot act’ (SAT 6.2.3, OCM II 314; LO 449). On theface of it, by claiming that laws, not bodies, are efficacious, Malebranche mayseem to be simply reintroducing genuine secondary causes into the world bythe back door. That is, instead of attributing causality to particular events orbodies, he is attributing it rather to the laws where these are understood to begeneral nomological facts. Causality, then, has been clandestinely shifted fromparticular bodies or events to structural features of the created world.16 But ifthis is so, then causal efficacy would still belong to creatures, and this claimwould be inconsistent with the fundamental occasionalist tenet that God is thesole true cause.At first sight there is a straightforward way of reconciling occasionalism

with the doctrine of efficacious laws. The key to solving the problem ofconsistency seems to be furnished by Malebranche’s insistence that efficaciouslaws are divine volitions. In Dialogues on Metaphysics XII.1 Malebranche’sspokesman claims that the laws of soul–body union are ‘but the constant andinvariably efficacious volitions of the Creator’ (OCM XII 279; JS 218). But ifefficacious laws are simply divine volitions, then they are not ontologically

interpretation of occasionalism that holds that within the order of nature God’s role is limited towilling the efficacious laws and the initial conditions of the universe. See A. Black, ‘Male-branche’s Theodicy’, Journal of the History of Philosophy 35 (1997), 40–4.

16 Some such criticism of occasionalism was made by Ralph Cudworth in his True IntellectualSystem of the Universe (1678), Book I, ch. 3, section 36. Cudworth criticizes ‘Mechanick Theists’who ‘would have God to contribute nothing more to the Mundane System and Oeconomy, thanonly the First impressing of a certain Quantity of Motion, upon the Matter, and the After-conserving of it, according to some General Laws’. Cudworth argues that these philosophers are,in spite of themselves, committed to his own theory of plastic natures:

Forasmuch as they must of necessity, either suppose these their Laws of Motion to executethemselves, or else be forced perpetually to concern the Deity in the Immediate Motion ofevery Atom of Matter throughout the Universe, in order to the Execution and Observationof them. The former of which being a Thing plainly Absurd and Ridiculous, and the Latterthat, which these Philosophers themselves are extremely abhorrent from, we cannot makeany other Conclusion than this, That they do but unskillfully and unawares establish thatvery Thing which in words they oppose; and that their Laws of Nature concerning Motion,are Really nothing else, but a Plastick Nature.

See C.A. Patrides (ed.), The Cambridge Platonists (Cambridge: Cambridge University Press,1980), p. 294. I am grateful to David Cunning for drawing my attention to this passage.



distinct from God himself. Thus there is no danger that the doctrine ofefficacious laws will reintroduce genuine causality into the world by the backdoor. On the contrary, it simply clarifies the nature of God’s unique causalactivity in the world.

This is a promising suggestion, but unfortunately the issue is not asstraightforward as this; it is complicated by the fact that, where divine volitionis concerned, certain distinctions need to be drawn. In the first place there isno doubt that, quite generally, Malebranche wishes to distinguish betweenvolitions and their upshots. Consider the case of a human being who raises hisor her arm, for example; here Malebranche will say that there is a volition thatis the occasional cause of its effect or upshot, namely, the movement of thearm (SAT 6.2.3, OCM II 315; LO 449). Moreover, prima facie we need todistinguish between the act of divine volition and its propositional content: avolition is a mental act whereby one wills that something or other be the case.Strictly speaking, then, when I will to raise my arm, I will that my arm go up. Ifefficacious laws are divine volitions, it seems that they must be identified withthe propositional contents of these volitions, and not with the acts themselves.As we shall see, each of these distinctions generates problems of interpretationfor the doctrine of efficacious laws.

I I I

According to Malebranche’s version of occasionalism, it is efficacious laws thatbring about particular events in the world. It is clear, then, that efficacious lawsbelong on the volition side of the divide between divine volitions and theirupshots; particular events, on the other hand, are the upshots of these voli-tions.17 In this way Malebranche can legitimately claim that laws are not partof the created furniture of the world. But if laws are volitions, and not theirupshots, then Malebranche has some explaining to do. For though Male-branche prefers to understand agency in terms of the volition/upshot model,he is clear that volitions and upshots may be related in quite distinct ways. Inthe case of human beings, the volition that one’s arm go up is, as we have seen,only the occasional cause of the movement of the arm. In the case of God, bycontrast, volitions are genuine causes of their upshots or effects by virtue of thefact that there is a necessary connection between the two. As Malebranche saysin The Search After Truth, ‘the mind perceives a necessary connection onlybetween the will of an infinitely perfect being and its effects’ (SAT 6.2.3, OCM

17 The point that for occasionalists laws of nature are identical with God’s volitions ratherthan the effects of them is emphasized by C.J. McCracken, Malebranche and British Philosophy(Oxford: Clarendon Press, 1983), p. 91.



II 316; LO 450). Malebranche is famously committed to what we may call the‘necessary connection’ principle concerning divine causality. Thus if Male-branche claims that efficacious laws bring about particular events in the world,he is committed to holding that there is a necessary connection between theselaws and the events that they produce. And it is not clear that Malebranche cansatisfy the demands of the ‘necessary connection’ principle.To appreciate the force of the problem, let us consider an alternative way of

applying the volition/upshot model to the case of divine agency. Suppose thatlaws of nature were to be regarded, not as divine volitions, but rather as theupshot of divine volitions. In this case there would be a straightforward andelegant way of satisfying the demands of the ‘necessary connection’ principle.To say that there is a necessary connection between God’s volitions and theirupshots would be to say that it is a necessary truth that if God wills the law ofinertia, for example, then the law of inertia obtains in the world. Of course thismodel is unsatisfactory on other grounds. If laws of nature are the upshots ofdivine volitions, then their home, as it were, is in the world; on this model theyare to be identified with those general structural features of the world that arethe truth-makers for nomological propositions. But in that case, laws of naturebecome creatures of a special sort, and thus, according to the fundamentaltenet of occasionalism, incapable of genuine causal efficacy. But flawed as it is,this model does have the merit of accommodating the ‘necessary connection’principle.Although there are compelling reasons for regarding the laws of nature as

volitions, not upshots, this approach cannot so easily accommodate the‘necessary connection’ principle. Recall that this principle states that there isa necessary connection only between the will of an infinitely perfect being andits effects. But it is natural to object that there is no necessary connectionbetween the laws of nature, taken by themselves, and particular events in theworld; that is, descriptions of such events do not follow from the laws of naturealone. As Jonathan Bennett remarks in another context, ‘if a particular clap ofthunder were necessitated by the laws of physics, there would be thundereverywhere and always’.18

The proper response to this objection is that our account of divine volitionsis incomplete as it stands. According to Malebranche, laws of nature are God’sgeneral volitions, and it is true that no such purely general volitions necessitateparticular events in the world, such as claps of thunder. But, as we have seen,God does not merely will the laws of nature; he also wills the initial conditions.Thus the divine volition that is necessarily connected with its effect is notsimple but compound; it is constituted by a general volition regarding the lawsof nature and a particular volition regarding the initial conditions of the

18 J. Bennett, A Study of Spinoza’s Ethics (Cambridge: Cambridge University Press, 1984),p. 113.



universe.19 On the assumption that the laws of nature are not merely probabil-istic, all particular events in the universe are indeed logically fixed by thiscompound divine volition.

Malebranche, then, is not merely committed to a volition/upshot model ofdivine agency; he is also committed to holding that the laws of nature belongon the volition side of the divide. But if this is the case, the doctrine ofefficacious laws is confronted by a new difficulty. Divine volitions are actsthat have propositional content, and it is with these propositional contentsthat laws of nature are to be identified; more strictly, laws of nature are thepropositional contents of divine general volitions. But understood in theseterms, laws of nature seem to be of the wrong ontological type to be capable ofcausal efficacy. Thus the doctrine of efficacious laws may seem to rest onsomething like a category mistake. It may, then, be doubted whether Male-branche subscribes to the doctrine in this form.

One way of responding to the objection is to draw on an analogy withMalebranche’s theory of ideas. Throughout his careerMalebranche is famouslycommitted to the thesis that all ideas are in God; by virtue of the fact that theypossess such properties as infinity, eternity, and necessity, God is the onlypossible locus for ideas. At least in his later philosophy Malebranche comes toadd a new property to the list: ideas in God are said to be efficacious; that is,they have the power to cause perceptions in finite minds.20 Scholars who havenoted this development inMalebranche’s teachings have wondered why he wasled to the theory of efficacious ideas. At least part of the answer seems to be thatMalebranche felt the need to respond to a challenge thrown down by Regis (seeOCM XVII-1 293–4). Malebranche is committed to the thesis that, in perceiv-ing ideas, the mind is united to God, and he had been pressed by Regis toexplain the nature of this union. Malebranche seems to have come to theconclusion that the only way of explaining the union was in causal terms.A further motive for the doctrine of efficacious ideas may have been moretheological. Malebranche seems to have felt the need to offer a stricter inter-pretation of the patristic thesis that the mind is an illuminated light (lumenilluminatum), not an illuminating light (lumen illuminans). To this end he

19 As Donald Rutherford emphasizes, creation itself must be regarded as the product of a‘particular volition’ that establishes the initial conditions of the world; see his ‘Malebranche’sTheodicy’ in S. Nadler (ed.), The Cambridge Companion to Malebranche, p. 171. It is not entirelyclear how many volitions (miracles aside) Malebranche wishes to ascribe to God: if, as Male-branche says at DMR VII.10 (OCM XII 160; JS 115), the conservation of creatures is a ‘singlevolition subsisting and operating continuously’, it is possible to see the natural order as fixed by asingle compound volition. In the Treatise of Nature and Grace (I.17, OCM V 31), however,Malebranche says that God is able to ‘produce an infinity of marvels with a very small number ofvolitions’. In any case it is clear that Malebranche wishes to keep the number of divine volitionsas low as possible.

20 See A. Robinet, Système et existence dans l’oeuvre de Malebranche (Paris: Vrin, 1965),p. 259.



comes to deny that the human mind possesses an inborn Cartesian faculty ofpure intellect whereby it apprehends ideas in God; the mind finds in itself onlymodalities full of darkness. But having deprived it of a faculty of pure intellectMalebranche needed to offer some account of how a purely passivemindwas intouch with the divine ideas: the theory of efficacious ideas fills the lacuna in histhought left by the disappearance of the faculty of pure intellect.21

The relevance of the doctrine of efficacious ideas for interpreting thedoctrine of efficacious laws should now be clear. It is widely agreed thatideas, for Malebranche, are not psychological items as they are for Descartes;by virtue of the fact that their locus is God who is outside space and time, theyare more like Platonic forms than Cartesian thoughts (cogitationes). Thus, inhis later philosophy, Malebranche is not reluctant to ascribe genuine causalproperties to abstract entities whose locus is God. Malebranche’s argument forthe attribution of causal properties to ideas is straightforward: ideas are inGod, and whatever is in God is efficacious; hence, ideas are efficacious (to deMairan, 12 June 1714, OCM XIX 884). Whatever we think of the merits of thisargument, it is nonetheless instructive for our present purposes, for it serves toshow that a similar argument can be constructed for the strict efficacy of laws:

1. Laws are propositional contents of divine general volitions.2. Propositional contents of divine general volitions are in God.3. Therefore, laws are in God.4. Whatever is in God is efficacious.5. Therefore, laws are efficacious.

Like the argument for the efficacy of ideas, this one is vulnerable to philo-sophical criticism. For instance, we might wish to dispute the premise thatwhatever is in God is efficacious; indeed, it seems to run together differentaspects of the divine nature that Malebranche had earlier insisted on distin-guishing. Nonetheless, it is clearly an argumentative strategy to which Male-branche might have appealed to defend his doctrine of efficacious laws againstthe charge that it is guilty of a category mistake.Impressed by the strangeness of ascribing causal properties to abstract

entities, some scholars have been inclined to doubt whether the theory ofefficacious ideas should be taken at face value. Alquié notes that Malebranchesometimes says, not so much that it is ideas that are efficacious, but rather thatit is God who acts in us by means of his efficacious ideas;22 in the Dialogues onDeath, for instance, Malebranche writes that ‘God alone . . . acts on our soulsby the idea of extension which he contains’ (OCM XII 409). According toAlquié, in such passages Malebranche is expressing himself more carefully; heis correctly attributing efficacy to the divine will rather than the divine ideas.

21 For further discussion of this issue see chapter 3 in this volume.22 F. Alquié, Le Cartésianisme de Malebranche (Paris: Vrin, 1974), pp. 210–11.



Some readers may wonder whether in a structurally similar way it is lawsthemselves that are efficacious. It may be said that talk of efficacious laws ismerely a façon de parler, and that efficacy strictly belongs not to the lawsthemselves but to the act of God’s volition in willing them.

Alquié’s scruples are understandable, but there are powerful considerationson the other side. For one thing, it is not clear that passages like the one fromthe Dialogues on Death really do offer a more careful alternative to the theoryof efficacious ideas. To say that God acts on our minds by means of his ideasmay mean simply that God acts on our minds precisely qua locus of effica-cious ideas. Moreover, not merely does Malebranche state the thesis of effica-cious ideas in uncompromising terms, as when he says that ideas are only theefficacious substance of the divinity (Conversations chrétiennes OCM IV 79);he also offers a direct argument for the thesis that suggests that he is un-troubled by the objection that abstract entities cannot have causal properties.As we have seen, Malebranche has the resources to offer a parallel argumentfor the efficacy of laws themselves. But even if, in the spirit of Alquié, we decideto say that talk of efficacious ideas is a façon de parler, one thing is clear: such aconcession has no tendency to give aid and comfort to the proponents of theNadler thesis. For what is at issue is whether it is laws themselves or God’saction in willing the laws to which efficacy properly belongs. Neither thesis hasany tendency to imply that in order to bring about particular events in theworld God has to do more than will the laws and the initial conditions.

A striking feature of Malebranche’s discussions of causality is that they tendto run the claim that laws are efficacious in tandem with the thesis that Godacts by or in consequence of his laws. This, I believe, is just what we shouldexpect, for Malebranche may well be seeking to assuage the worry that to talkof efficacious ideas is to reintroduce secondary causality into the world by theback door. Malebranche seems to be responding to this objection by empha-sizing that it is precisely by means of efficacious laws that God, the uniquecausal agent, acts in the world; the doctrine of efficacious laws is thus in noway inconsistent with the central tenet of occasionalism. But whatever hisreasons for running the two doctrines in tandem, it is fortunate for ourpurposes that he does so; for he thereby makes it clear that God does notneed to implement the laws that he has willed through a series of discreteindividual volitions.



7

Leibniz and Malebranche on Innate Ideas

Everyone knows that Locke attacked, and Leibniz defended, the doctrine ofinnate ideas. But it is much less well known that innate ideas were attacked byone seventeenth-century philosopher who is conventionally classified as a ration-alist: in The Search After TruthMalebranche explicitly rejects the doctrine whichhis predecessor, Descartes, had revived (SAT 3.2.4, OCM I 429–32; LO 226–7). Inview of his philosophical allegiancesMalebranche’s stand is somewhat surprising.As a philosopher in the Platonic and Cartesian traditions Malebranche might beexpected to be found among the partisans rather than the enemies of innate ideas.But thoughMalebranche’s oppositionmay surprise us, wemaywonder how deepit goes. It is notoriously difficult to see what is at issue in seventeenth-centurycontroversies over innate ideas; parties to the debate tend to resort to picturesquebut unhelpful metaphors. Some philosophers may be inclined to suppose thatMalebranche’s opposition to the doctrine can be little more than verbal. Suchscepticism, however, would be amistake. Malebranche’s case against innate ideasis in some ways more radical and important than Locke’s, and there is reason tobelieve that Leibniz would have shared this estimate.When Leibniz champions the doctrine of innate ideas, he is in effect fighting

a war on two fronts. On the one hand of course (at least in his later writings),he is attacking Locke’s view that the mind at birth is a tabula rasa; on the otherhand, he is combatting the theory of ideas espoused by Malebranche. The factthat Malebranche is a target can, I believe, throw new light on Leibniz’ssometimes obscure defence of innate ideas; for many features of Leibniz’scase fall into place once they are seen as a part of a coherent strategy foranswering Malebranche’s objections. An analysis of Leibniz’s strategy can alsohelp to illuminate some of the deepest themes and tensions in his philosophy.We shall see, for example, that in order to defend the ‘Platonic’ doctrine ofinnate ideas, Leibniz is forced to draw heavily on nominalist and reductioniststrategies. My aim in this essay is not primarily to establish that Leibniz alwayshad Malebranche in mind when defending innate ideas; it is rather to showthat an important debate on this issue can be derived from the writings of thetwo philosophers. But it will be helpful to begin by providing a brief sketch ofLeibniz’s dealings with Malebranche.


Leibniz maintained an active interest in Malebranche’s philosophy forabout forty years. The two men had become acquainted in 1675, the penulti-mate year of Leibniz’s stay in Paris, and they corresponded thereafter on anirregular basis until Malebranche’s death in 1715. Much of this correspond-ence turned on issues in physics; Leibniz was particularly anxious to persuadeMalebranche that the Cartesian laws of motion were fundamentally flawed(Leibniz to Malebranche, undated, G I 349 ff.). In his private papers and someof his published works, however, Leibniz leaves us a substantial record of hisreactions to Malebranche’s purely philosophical doctrines. Malebranche’stheory of ideas was the immediate stimulus for Leibniz’s first major ventureinto epistemology; the well-known Meditations on Knowledge, Truth, andIdeas (1684) opens with an allusion to the controversy between Malebrancheand Arnauld on the nature of ideas.1 Two years later, in the Discourse onMetaphysics (1686), Leibniz criticizes Malebranche’s doctrine of vision in God,and sketches his own theory of innate ideas as an alternative thesis (DM 26–29, G IV 451–4; L 320–1). Thus, four years before the publication of Locke’sEssay and nearly twenty years before he wrote the New Essays, Leibniz waschampioning innate ideas against a philosopher who dismissed them. When,in the New Essays, Leibniz came to mount a full-scale defence of innate ideas,he repeated and developed many of the points he had earlier made in responseto Malebranche. And in the last years of his life Malebranche’s philosophyprovided the stimulus for one of Leibniz’s most brilliant short works; theConversation of Philarète and Ariste was written as a continuation of Male-branche’s own Dialogues on Metaphysics (G VI 579–94; L 618–28). Thusalthough Leibniz never devoted a full-scale commentary to Malebranche’sphilosophy, he found a number of opportunities to take issue with it; oftenMalebranche is the unnamed and indirect target of attack. In many waysLeibniz was drawn to the Platonic and Augustinian tendencies of Male-branche’s philosophy, but as we shall see, he could not accept his doctrine ofideas and its commitment to abstract entities.

I

Although Malebranche has an effective case against innate ideas, it is not wellpresented in his most famous work, The Search After Truth. Arnauld com-plained with some justice that in the central epistemological section of thiswork Malebranche seems to run together two questions; he does not clearlydistinguish between the question of the nature of ideas and the question of

1 ‘Distinguished men are today engaged in controversies about true and false ideas’ (G IV 422;L 291).



their origin.2 Malebranche confuses the reader by tackling the latter issue as ifhe shared basic Cartesian assumptions about the nature of ideas; the famousdoctrine of vision in God is introduced as if it offered a superior account ofidea-acquisition from within the Cartesian framework. In fact Malebranche’sepistemology is such that the whole issue of the origin of ideas turns out to bemisconceived. Relatedly, the objections to innate ideas which Malebranchedoes parade in this section are by no means his most powerful; they are almostin the nature of afterthoughts to his real case. Despite these failures ofpresentation, a major case against innate ideas can be derived from Male-branche’s writings as a whole.(i) Malebranche’s most basic argument against innateness flows directly

from his doctrine of the nature of ideas. Reduced to its essentials, the argumentis remarkably simple. Ideas, according to Malebranche, are not in the mind atall; indeed, they are not the sort of entities which could be in a mind. So if thereare, and could be, no ideas in a mind at any time, a fortiori there are no innateideas.To understand this argument we need to realize that the most basic theme

of Malebranche’s doctrine of ideas is its resolute anti-psychologism. Far morethan any other seventeenth-century philosopher in the Cartesian tradition,Malebranche insists that logic and psychology must not be conflated. Inparticular, we need to distinguish carefully between the thought (that is,thinking) of x and the concept or idea of x.3 The former is a particular mentalevent which exists at a particular time; in Malebranche’s terms, it is a modifi-cation or modality of the human mind. The latter, by contrast, is an abstractentity which exists over and above these modifications. It is true that Male-branche locates ideas, the abstract items, in God, and this may seem to qualifyhis anti-psychologism. But Malebranche resists any attempt to reduce ideas orconcepts to divine occurrent thoughts. Although it is obscure just how ideasare supposed to be in God, it is clear that they are not events in his mind;indeed they do not seem to be mental contents at all.4

Malebranche’s theory of ideas naturally invites comparison with Descartes’.We can make the comparison by considering how the two philosophers wouldanalyse the case of someone thinking of a triangle in general. Descartes will say

2 A. Arnauld, Des Vraies et des Fausses Idées, Oeuvres De Messire Antoine Arnauld (Paris andLausanne: Sigismond D’Arnay, 1775–83: reprinted Brussels: Culture et civilisation, 1964–67),vol. 38, p. 340.

3 For helpful comments on the apparent conflation of logic and psychology in Locke andLeibniz, cf. the Introduction to the abridged edition of the Remnant and Bennett translation ofthe New Essays (Cambridge: Cambridge University Press), p. xxii. I am also indebted toJ. Bennett, ‘Locke, Leibniz, and the Third Realm’, unpublished paper read to a conference onLocke and Leibniz at Rice University, November 1982.

4 Malebranche insists that ideas are not created; they are the essence of God himself in so faras he is participated in by creatures. OCM VI 118, 125. Cf. DMR II, OCM XII 51; JS 21.


Leibniz and Malebranche on Innate Ideas 107

that there is one item here, an idea, which has two irreducible aspects. On theone hand, there is its aspect as a particular thought or modification of themind; translating Descartes’ terminology into modern English, we can say thatthis is its intrinsic reality. On the other hand, there is the object or content ofthe idea, namely, the triangle in general; again translating Descartes’ termin-ology, we can say that this is its representative reality (Meditations III, AT VII40–1; CSM II 27–8). Malebranche, by contrast, will claim that there is not oneitem here but two which need to be carefully distinguished: there is boththought or perception (the modification of the mind), and the idea (theabstract entity). For Malebranche, when two people think of a triangle ingeneral, they may be said to be thinking of the very idea, although theiroccurrent thoughts are numerically distinct and peculiar to their minds.

For strategic reasons Malebranche sometimes conveys the impression thathe is merely clarifying Descartes’ own theory of ideas. But at other times headmits that he is making a major revision in the theory. Descartes, he claims,did not get to the bottom of the nature of ideas (OCM VI 214). Malebranchebrings out his difference from his predecessor by using the terminology thatDescartes himself employed:

Mr. Descartes says that ideas are modalities of minds. That’s true [that is, thatDescartes says this]: but it’s because, unlike me, he does not take the word ‘idea’ tosignify exclusively the ‘representative reality’, but for those sorts of thoughts bywhich one perceives a man, an angel etc.

(OCM VI 217)

It would seem that, for Malebranche, Descartes’ pronouncements on ideas areopen to two major objections. First, for Descartes, ideas are sometimescontents and sometimes mental events which have contents.5 Thus, in Des-cartes’ writings, questions of the form: ‘How many ideas have I had during thelast five minutes?’ tend to be systematically ambiguous. Secondly, Male-branche would argue that, even if this muddle is straightened out, Descartes’theory does not explain adequately how two people can be said to have thevery same idea: for Descartes, this would seem to be a mere façon de parler.Nor can Descartes explain how ideas can pre-exist and post-exist particularacts of thinking. For the idea of a triangle did not come into existence whensomeone first thought of a triangle, and it will not cease to exist when the lasttriangle-thinker has expired.

It should be clear, then, how Malebranche will address the issue of innateideas. According to Malebranche, once we resist the temptation to conflate

5 Cf. Malebranche’s judgement on Locke: ‘At a time when the errors of English authors,Hobbes, Locke and some others are propagated everywhere and do too much damage to remainsecret, one must not make fun of this principle, That ideas are different from the perceptions wehave of them; that they are eternal and immutable, and our perceptions transitory’ (OCMXV 51–2).



ideas and thoughts or perceptions, we must realize that the question ofwhether there are any innate ideas makes no sense. Indeed, the whole doctrineof innate ideas turns out to be based on a conflation of logic and psychology. Ifa person speaks of items as being in the mind—for example, saying that theyare there from birth—then he must be talking about modifications of themind. But ideas are not modifications of the mind. Thus there are, and can be,no innate ideas.As an initial response to this line of argument one might grant the distinc-

tion between ideas and thoughts, and then insist that what is at issue iswhether there are any innate thoughts. Now Malebranche sometimes seemsto play down the need for thoughts or perceptions corresponding to ourapprehension of ideas. But his considered view, I take it, is that when I thinkof a triangle, my mind is modified in a certain way, and this modification iswhat he calls a ‘pure perception’ (Christian Conversations, OCM IV 75–6).6

Malebranche can reply to his opponent that he cannot be satisfied with innateperceptions. For it is surely an essential part of the doctrine of innate ideas thatthey persist through time; to have an innate idea is to be in a persistent mentalstate. Indeed, the defender of the doctrine will no doubt claim that the mind isin this state from birth and remains in it throughout its history. But percep-tions are essentially transitory; in a favourite phrase of Malebranche’s, they are‘passagères’. Thus the champion of innate ideas cannot rescue his thesis bysimply replacing ‘ideas’ with ‘perceptions’. Malebranche can in fact confronthis opponent with a dilemma. The items that are supposed to be innate areeither ideas or perceptions. If they are ideas, then the whole issue is miscon-ceived; if they are perceptions, they cannot have the degree of permanencewhich they are required to have. Malebranche might perhaps reinforce thesecond horn of the dilemma in a Lockean way: he might argue that it isempirically false that there are innate perceptions of ideas such as triangles.(ii) Simply substituting talk of perceptions for talk of ideas is thus a mere

provisional move which Malebranche can easily counter. But readers who arefamiliar with the wider history of the controversy will know that the defenderof innate ideas is likely to opt for a different strategy: he will reformulate hisclaim in a more basic way. Descartes, for example, might grant everything thatMalebranche says so far, but he will insist that the mind has innate ideas in thesense that it has a faculty or disposition to form certain thoughts. Descartes’most famous expression of this line of defence occurs in the Comments on aCertain Broadsheet:

6 See D. Radner, Malebranche (Assen: Van Gorcum, 1978), p. 86. Malebranche usuallydiscusses the mind’s modifications in the context of talk about what he calls ‘sentiments’—thatis, secondary qualities and pain sensations, etc. According to Malebranche, ‘sentiments’ lack anycorresponding idea.



I have never written or taken the view that the mind requires innate ideas whichare something distinct from its own faculty of thinking. I did, however, observethat there were certain thoughts within me which neither came to me fromexternal objects nor were determined by my will, but which came solely fromthe power of thinking within me; so I applied the term ‘innate’ to the ideas ornotions which are the forms of these thoughts in order to distinguish them fromothers, which I called ‘adventitious’ or ‘made up’. This is the same sense as that inwhich we say that generosity is ‘innate’ in certain families, or that certain diseasessuch as gout or stones are innate in others; it is not so much that the babies ofsuch families suffer from these diseases in their mother’s womb, but simply thatthey are born with a certain ‘faculty’ or tendency to contract them.

(AT VIIIB 357–8; CSM I 303–4)

In this way Descartes can meet the objections which Malebranche has pressedso far. This version of the doctrine at least avoids the charge of crudepsychologism, for it is clear that despite his terminology, Descartes is talkingabout a disposition to have certain mental events under certain conditions.And it also does justice to the claim that innate ideas persist through time; forwhat persists is not particular thoughts or perceptions, but the disposition tohave those thoughts. The appeal to talk of faculties or dispositions also enablesDescartes to meet the empirical worry that infants do not seem to engage inabstract thought of a metaphysical or mathematical variety.

The champion of innate ideas is almost forced to fall back on a second lineof defence, but Malebranche is waiting for him. We now come to Male-branche’s second major criticism of Descartes. In Elucidation X of The SearchAfter Truth Malebranche complains that there is a serious inconsistency inDescartes’ meta-explanatory principles. In his physics Descartes of courseinsists that all appeal to faculties, natures, or occult qualities must be banished;in their place will be explanations which appeal solely to the actual quantifiableproperties of bodies. Yet when it comes to the mind, Descartes gets cold feet;he is indulgent towards the pseudo-explanatory talk of faculties which he hadrightly dismissed in the case of physical phenomena:

I am amazed that the Cartesian gentlemen who so rightly reject the general termsnature and faculty should so willingly employ them on this occasion. Theycriticize those who say that fire burns by its nature or that it changes certainbodies into glass by a natural faculty, and yet some of them do not hesitate to saythat the human mind produces in itself the ideas of all things by its nature,because it has the faculty of thinking. But with all due respect, these terms are nomore meaningful in their mouth than in the mouth of the Peripatetics.

(OCM III 144; LO 622)

Malebranche’s attack is perhaps too sweeping, but we can restate and develophis objection in the following way. The theory of innate ideas, if it is anythingat all, is put forward as an explanatory hypothesis about idea-acquisition.



Purged of objectionable psychologism, this means that it is an explanatoryhypothesis about the occurrence of certain thoughts in human minds: forexample, John’s thought of a triangle at t. Malebranche may concede to hisopponents that innate ideas are not intended to tell the whole causal story:some external stimulus will be additionally required. But he will still insist thatthe innatist hypothesis is intended to state at least a causally necessary condi-tion for the existence of certain thoughts, and thus must be contentful. Butwhen the defender of innate ideas resorts to talk of faculties, his claim must beempty unless such faculties can be grounded in non-dispositional properties ofthe mind. In the case of physical objects it is possible to see how such agrounding requirement can be satisfied; the non-dispositional properties willtypically be persistent structural modifications of the kind discovered byscience. But no such solution seems readily available to the defender of innateideas, for it is not clear how one can speak of persistent structural modifica-tions in the case of immaterial minds. Thus the hypothesis of innate ideas is indanger of being explanatorily empty.Malebranche’s anti-psychologism and his attack on faculty explanations are

the core of his case against innate ideas; taken together, they form a powerfultwo-stage argument against the doctrine. However, in the section of TheSearch After Truth explicitly devoted to innate ideas, Malebranche argues ina more popular and superficial manner. He does not choose to submit thepresuppositions of the doctrine to any searching scrutiny; indeed, given hisstrategy of presentation, he is not really in a good position to do so, for he hasnot yet fully explained his anti-Cartesian theory of ideas. Instead, he argueslargely on his opponents’ own ground; he seems to accept that one cancoherently conceive of a stock (magasin) of innate ideas. Malebranche infact advances two arguments which he admits are less than conclusive. Sincethey are not central to his case, we can afford to deal with them quite briefly. Itshould be noted, however, that each is fully countered by Leibniz, and this isperhaps their chief claim to importance.(iii) According to Malebranche, the doctrine of innate ideas is a clumsy

hypothesis which is inconsistent with the simplicity of the divine ways.Malebranche invites us to consider the implications of the claim that allideas are innate:

[The mind], then, has an infinite number of ideas—what am I saying?—it hasas many infinite numbers of ideas as there are different figures; consequently,since there is an infinite number of different figures, the mind must have aninfinity of infinite numbers of ideas just to know the figures.

(SAT 3.2.4, OCM I 430; LO 227)

Malebranche’s opponent is thus forced to postulate that the mind is createdwith an infinitely large stock (magasin) of innate ideas. But since God alwaysacts in the simplest ways, it is probable at least that he chose some other way ofstocking the mind with its contents.



(iv) Even if such a store is granted, Malebranche argues, his opponentcannot explain how the mind can select among its ideas. Suppose a personis perceiving the sun; a sensory idea, then, must be drawn out of the store-house. If this selection is not to be arbitrary, the mind must follow a rule. WhatMalebranche seems to envisage is that the rule would specify the selection ofthe idea which maximally resembles some given pattern; consider, analo-gously, the role of samples in choosing a colour. But, according to Male-branche, it is difficult to see what such a pattern could be. It cannot be theretinal image, for there is no resemblance between retinal images and ideas,and in any case, the mind does not perceive such images (SAT 3.2.4, OCMI 430; LO 227). Nor will it help to suggest that the pattern in question could bean idea. For if all ideas have to be selected, and only ideas can guide theselection, then we are involved in an infinite regress.7

A difficulty with these arguments is to decide exactly what version of thedoctrine of innate ideas is their target. Superficially, this should not be aproblem. Malebranche is explicit that he is attacking a strong version of thedoctrine which holds that ‘all ideas are innate or created with us’ (SAT 3.2.4,OCM I 429; LO 226). The second argument, in particular, seems to be directedagainst an opponent who holds that all our sensory ideas—that is, sense-perceptions—are innate. Such a thesis may be espoused by a philosopher who,with Malebranche, denies that there is any causal interaction between mindand body. Descartes himself seems to flirt with such a thesis on occasion, andit is confidently embraced by Leibniz in his deep metaphysics (in contrast tomore popular works such as the New Essays).

But it is not entirely clear that this is the right identification of Male-branche’s target, and the problem of interpretation stems from his refusal, atthis stage, to specify how far he is accommodating himself to the Cartesiantheory of innate ideas. Recall that when Descartes seems to advance a strongversion of innatism, he leaves no doubt about what is involved; he is explicitthat colour perceptions and pain sensations are included:

[T]he very ideas of the motions themselves and of the figures are innate in us. Theideas of pain, colours, sounds and the like must be all the more innate if, on theoccasion of certain corporeal motions, our mind is to be capable of representingthem to itself, for there is no similarity between these ideas and the corporealmotions.

(AT VIIIB 359; CSM I 304)

For Malebranche, however, there are in strictness no ideas of pain and colour,but only sensations (sentiments) of them. For it is of the nature of ideas torepresent truly the properties of objects, and Malebranche holds a strong

7 Cf. W. Doney, ‘Malebranche’, in Paul Edwards (ed.) Encyclopedia of Philosophy (New York:Macmillan, 1967), vol. 5, p. 142.



version of the seventeenth-century doctrine that physical objects have onlyprimary qualities. We are now concerned with a different contrast betweenDescartes and Malebranche from the one we discussed earlier. The point hereis not that, for Malebranche, ideas are abstract entities; it is that, beingrepresentative by their nature, they must correspond to genuine propertiesof the world.There is no doubt, then, that Malebranche is attacking a strong version of

the innatist hypothesis. But unless he is adapting totally to the Cartesianterminology at this stage, it is not clear that the thesis he opposes allowsroom for innate ideas of pain and colour. To this extent the thesis inquestion is not as strong as that which Descartes sometimes entertains,and to which Leibniz is committed in his deep metaphysics. But it is clearthat Malebranche is attacking a thesis which maintains that sense-percep-tions of primary qualities are innate; for these figure explicitly in thediscussion (SAT 3.2.4, OCM I 431; LO 227). Thus Malebranche’s target isimportantly similar to Cartesian and Leibnizian versions of the thesis that allideas are innate.

II

Perhaps the most obvious characteristic of Leibniz’s reaction to Malebranche’sphilosophy in general is his desire to find common ground. Commenting onMalebranche’s doctrine of vision in God, Leibniz habitually remarks that itcontains at least a kernel of truth: Malebranche is right that God is the onlyimmediate external object of our minds.8 What Leibniz means by this is thatGod is the only substance that can act causally on our minds; in other words,Malebranche is right to deny interaction between finite substances. And indefending innate ideas against Malebranche Leibniz frequently adopts a con-ciliatory tone; he seems to regard him as a worthier opponent than Locke.9

Yet more important philosophically is the strongly reductionist character of

8 For statements of this view see Leibniz to Foucher, September 1696, G I 423; Leibniz toCoste, 16 June 1707, G III 392; Leibniz to Remond, 4 November 1715, G III 659–60.

9 Indeed, Leibniz explicitly compares Malebranche favourably with Locke:

Although Locke’s book on the human understanding contains much that is of great value,I found it fundamentally unsatisfactory. He did not adequately appreciate the dignity of ourmind, nor did he adequately understand that the principles of necessary truths are latent init, nor did he adequately distinguish these from others; and on the whole he tends rather toconfirm common opinions than to establish sound judgements. Plato, Aristotle, Descartes,Hobbes in places and Malebranche wrote with much more depth.

Leibniz to Bierling, Leibniz Briefwechsel 67, 51v, Niedersächsische Landesbibliothek, Hanover.This is the first draft of a letter to Bierling dated 24 October 1709 (G VII 485).



Leibniz’s defence strategy; indeed, we shall see that Leibniz’s reductionismcomes in two stages and works in two distinct ways. Sometimes it is deployedas a means of accommodating Malebranche’s insights; at other times it isdeployed as a means of deflating his objections to the doctrine of innate ideas.In both cases it serves to meet the requirements of a nominalistic metaphysicswhich countenances only individual substances and their states.

Let us now see how Leibniz responds to each of Malebranche’s objectionsin turn.

(i) In some early notes on Foucher’s critique of the Search, Leibniz shows thathe has a firm grasp of Malebranche’s ‘Platonic’ theory of ideas. Leibniz alsoinsists on the dangers of equivocation: a clear distinction must be made betweenideas as objects or contents of thought and ideas as particular mental events:

‘Ideas’ can be taken in two senses: namely, for the quality or form of thought, asvelocity and direction are the quality and form of movement: or for the immedi-ate or nearest object of perception. Thus the idea would not be a mode of being ofour soul. This seems to be the opinion of Plato and the author of the Recherche.For when the soul thinks of being, identity, thought, or duration, it has a certainimmediate object or nearest cause of its perception. In this sense it is possible thatwe see all things in God and that the ideas or immediate objects are the attributesof God himself. These formulas or modes of speaking contain some truth, but tospeak correctly it is necessary to give constant meanings to terms.

(MLR 73; L 155; cf. DM 26, G IV 451; L 320)

In the New Essays Leibniz clearly indicates his own preference for interpretingideas as objects to which the mind is related in thinking:

If the idea were the form of the thought, it would come into and go out ofexistence with the actual thoughts which correspond to it, but since it is the objectof thought it can exist before and after the thoughts.

(NE II.1, A.VI.vi; RB 109)

These texts reveal an important measure of agreement between the two phil-osophers. For Leibniz, as for Malebranche, there can be no straightforwardidentification of ideas with particular thoughts, for thoughts have propertieswhich are not possessed by ideas.We can say of thoughts that they are transitoryand that they occur at particular times, but we cannot say this of ideas.

It might seem, then, that Leibniz and Malebranche are in complete agree-ment on the nature of ideas. Certainly there are occasions when Leibnizsounds very much like Malebranche; following Malebranche’s own mentor,Augustine, Leibniz speaks of God as the ‘region of ideas’ (G VII 305; L 488).We might suppose that Leibniz can have no objection to regarding ideas asirreducibly abstract entities. But this would be a mistake. As Mates observes,for all his fondness for talk of ideas, essences, and possible worlds, Leibniz is infact a nominalist who cannot countenance abstract entities as basic items of



ontology.10 In other words, Leibniz holds that there are no entities named byabstract nouns such as ‘heat’ and ‘justice’. Thus, statements which appear to beabout such entities can be rephrased as statements in which the abstract termsare replaced by concrete nouns and adjectives. In a passage in which Leibnizexplains his views, he is prepared to describe himself, at least tentatively, as anominalist:

Up to now I see no other way of avoiding these difficulties than by consideringabstracta not as real things (res) but as abbreviated ways of talking (compendialoquendi)—so that when I use the name heat it is not required that I should bemaking mention of some vague subject but rather that I should be sayingthat something is hot—and to that extent I am a nominalist, at least provisionally.

(Gr II 547)11

Leibnizmay allow us to talk of ideas, essences, and possible worlds, but he holdsthat when we do so, we are using expressions which are mere compendialoquendi; they are convenient, abbreviated ways of speaking which do notaccurately describe reality. In metaphysical rigour there are no abstract entities;there are only individual substances (including God) and their affections.Leibniz’s agreement with Malebranche is thus much less thorough-going

than it sounds. Ideas, for Leibniz, are not some ‘third realm’ existing over andabove particular acts of thinking. Although he resists any straightforwardidentification of ideas with thoughts, Leibniz does believe that talk aboutideas can be reduced to talk about the mental. Leibniz brings off the reductionby explaining that ideas are dispositions to think in certain ways. In the earlypaper, What is an Idea?, Leibniz states this view with admirable clarity:

There are many things in our mind, however, which we know are not ideas,though they could not occur without ideas—for example, thoughts, perceptions,and affections. In my opinion, namely, an idea consists not in some act, but in thefaculty of thinking, and we are said to have an idea of a thing even if we do notthink of it, if only, on a given occasion, we can think of it.

(G VII 263; L 207)12

It is clear from this passage that there is no inconsistency between Leibniz’snominalist intolerance of abstract entities and his agreement with Male-branche that ideas are not particular thoughts. Leibniz adopted this solutionto the problem early, and he seems never to have abandoned it.

10 B. Mates, The Philosophy of Leibniz (New York and Oxford: Oxford University Press,1986), esp. p. 246. I am much indebted to Mates’ persuasive discussion of the nominalistictendencies of Leibniz’s philosophy.

11 Quoted and discussed in Mates, The Philosophy of Leibniz, p. 171.12 This paper may have been prompted by Leibniz’s reading of both Malebranche and

Spinoza. On Leibniz’s theory of ideas as faculties, see R. McRae, ‘ “Idea” as a PhilosophicalTerm in the Seventeenth Century’, Journal of the History of Ideas 26 (1965), 175–90.



We can now see how Leibniz would counter Malebranche’s first argumentagainst innate ideas. Malebranche argues that ideas are not in the mind becausethey are abstract objects. Leibniz can reply that Malebranche is setting up a falsedichotomy betweenmental items (thoughts) and non-mental ones (ideas). Ideasare mental because they are dispositions to form certain thoughts under certainconditions, and these dispositions are predicated of individual minds. The veryfirst point that Leibniz makes in the paper, What is an Idea?, is that an idea is‘something which is in themind’, and he never retreats from this position (GVII263; L 207).13 Thus, by reducing ideas to dispositions, Leibniz has counteredMalebranche’s argument to the effect that the whole issue of innate ideas ismisconceived. For Leibniz, there is no philosophical impropriety in treatingideas as mental items. Innate ideas are thus at least a conceptual possibility.

(ii) If ideas are dispositions to think in certain ways, then innate ideas areinnate dispositions to think in certain ways; in other words, they are dispos-itions which we have had at least since birth. This of course is precisely thedoctrine that Leibniz defends against Locke in the New Essays: ‘This is howideas and truths are innate in us—as inclinations, dispositions, tendencies ornatural virtualities, and not as actions’ (NE, Preface, A VI.vi; RB 52). But nowLeibniz must cope with Malebranche’s second wave of attack, for as we haveseen, Malebranche insists that talk of mental faculties or dispositions is essen-tially vacuous.14

Once again, Leibniz’s reply would be initially conciliatory in tone. Leibniz, asa mechanistic physicist, joins Malebranche in condemning the circular facultyexplanations of the Scholastics; in the New Essays he ridicules those who saythat clocks tell the time by virtue of a horological faculty (NE, Preface, A VI.vi;RB 68). Indeed, as is well known, Leibniz is so much a child of his time that heworries about Newton in this respect; he accuses him of reintroducing occultqualities, and of thereby abandoning the foundations on which the new physicshad been established.15 And in the New Essays Leibniz seems no more indul-gent to talk of faculties when it comes to the mind. Ironically, Leibniz accusesthe empiricist Locke of being committed to ‘bare faculties’with his tabula rasa:

It may be said that this ‘blank page’ of the philosophers means that all the soulpossesses, naturally and inherently, are bare faculties. But inactive faculties arealso mere fictions, unknown to nature and obtainable only by abstraction. For

13 Cf. DM 26: ‘I believe that this quality of our soul, insofar as it expresses some nature, form,or essence, is properly the idea of the thing which is in us and is always in us whether we think ofit or not’ (G IV 451; L 320). Occasionally (G III 659; cf. G IV 426; L 294), Leibniz even says thatideas are modifications of our soul, but this seems to be going beyond his official position.

14 Cf. T.M. Lennon: ‘Malebranche no more than Locke is content to view the mind aspossessed of dispositional qualities’ (Philosophical Commentary, LO 784).

15 On this issue see N. Jolley, Leibniz and Locke: A Study of the New Essays on HumanUnderstanding (Oxford: Clarendon Press, 1984), ch. 4.



where will one ever find in the world a faculty consisting in sheer power withoutperforming any act?

(NE II.1, A VI.vi; RB 110)16

For Leibniz, then, it is precisely the denial of innate ideas which involves anobjectionable commitment to faculty talk.At first sight it may seem that Leibniz is caught in an inconsistency. It may

seem as if he simultaneously accepts and rejects faculties with regard to themind. But in fact there is no such incoherence in Leibniz’s position. UnlikeMalebranche, Leibniz makes a distinction between ‘bare faculties’ on the onehand and dispositions on the other. As Leibniz tells Burnett, ‘there is not onlyin our mind a faculty but a disposition to knowledge’ (3 December 1703, G III291). Leibniz’s terminology is thus not quite consistent; for what he terms‘faculty’ [facultas] in the paper,What is an Idea?, presumably corresponds to adisposition in the New Essays. ‘Bare faculties’ are indeed an unfortunate legacyof Scholasticism; they are fictions, and can be eliminated. But dispositions areon a different footing; for they can be grounded in the categorical properties ofindividual substances.Leibniz’s defence of innate ideas as innate dispositions would take some

form like the following. For Leibniz, as for most of us, when we ascribe adispositional property to an object, there must be some categorical property invirtue of which it is ascribed; this categorical property will typically be apersistent structural modification. Thus, in what Mates calls the paradigmaticexample, the sugar is soluble in virtue of its crystalline structure; the structuraldescription of the sugar, together with an appropriate law of nature, jointlyentail that the sugar is soluble in certain conditions.17 In Leibniz’s view, justthe same basic principles apply when we ascribe a dispositional property to themind; for example, when we say that an infant’s mind has an innate idea of atriangle. There is the same basic need for a persistent structural modification,but in this case it must be a purely mental one. Now, as Broad says, and as wehave already seen, it is not entirely clear what is involved in ascribing apersistent structural modification to an immaterial mind; it cannot be thoughtof as a modification in spatial arrangement or motion of particles.18 Broad’ssolution to the problem seems just right:

It seems to me that the view which Leibniz took was that the modification simplyis a persistent but unconscious experience. E.g. during intervals when I shouldordinarily be said not to be thinking of the fact that 2 + 2 = 4 and not to beremembering the late Master of Trinity, I am really continuously thinking of theformer and remembering the latter in a perfectly literal non-dispositional sense.

16 For Leibniz’s critique of the doctrine of the tabula rasa, see Jolley, Leibniz and Locke, ch. 9.17 Mates, The Philosophy of Leibniz, p. 246.18 C.D. Broad, Leibniz: An Introduction (Cambridge: Cambridge University Press, 1975),

p. 134.



But at such times these experiences are unconscious. At times when it wouldordinarily be said that the mere cognitive disposition gives rise to an actualexperience what really happens is that the cognitive process which has beengoing on all the time becomes conscious. Thus for Leibniz any evidence forcognitive dispositions would ipso facto be evidence for unconscious cognitiveexperiences.19

Thus, for Leibniz, a child’s mind possesses an innate disposition to think of atriangle by virtue of a mental modification, and this mental modification is apersistent unconscious perception with triangle content.

We can now see that Leibniz’s defence strategy involves a two-fold reduc-tion. Innate ideas are first reduced to innate dispositions to think in certainways. Innate dispositions to think in certain ways are then in turn reduced tounconscious experiences or petites perceptions. In other words, Leibniz holdsthat from a description of a mind’s unconscious experiences, together with thelaws of psychology, we could infer that it would have the conscious thought ofa triangle under certain specifiable conditions. In this way Leibniz can recon-cile his commitment to innate ideas with his nominalistic conviction that thereare only individual substances and their states.

(iii) We have seen that in The Search After Truth Malebranche argues thatthe doctrine of innate ideas is contrary to the simplicity of the divine ways.Here, too, Leibniz must concede that if the objection could be made to stick, itwould be grounds for rejecting the doctrine; for according to Leibniz’s principleof the best, God shows a preference for the simplest laws consonant with themaximum variety of the phenomena (DM 6, G IV 431; L 306). Thus Leibnizmust show that the doctrine of innate ideas is in fact the simplest explanationof the phenomena; it is not the clumsy hypothesis that Malebranche takes itto be.

Leibniz can offer a double-barrelled reply to Malebranche’s objection. Hecan meet the challenge by distinguishing between two levels of analysis. On theone hand, he can answer the objection at the level of ideas; on the other hand,he can answer it at the level of thoughts or, in his scheme, perceptions.

When Malebranche’s objection is interpreted in the former way, Leibnizcan turn his opponent’s weapons against him. In controversy with Arnauld,Malebranche observes that ideas are not discrete items, but are logicallyinterrelated. For example, the idea of extension, or what Malebranche callsintelligible extension, potentially contains all possible geometrical figureswithin it. What Malebranche seems to mean by this is that the properties ofall possible geometrical figures can be derived from basic geometrical axioms

19 Broad, Leibniz: An Introduction, pp. 134–5. Cf. NE Preface, A VI.vi; RB 52: ‘thesevirtualities (virtualitez) are always accompanied by certain actions, often insensible ones,which correspond to them’.



and definitions. Malebranche makes use of an image that Leibniz was to makefamous in the New Essays:

As in a block of marble all possible figures are potentially in it, and can be drawnout of it by the movement or the action of the chisel, so in the same way allintelligible figures are potentially in intelligible extension and are discovered in itaccording to the different ways in which this extension is represented to the mind,as a consequence of the general laws which God has established and according towhich he continuously acts in us.

(OCM VI 208–9)

Adapting Malebranche’s own example, Leibniz could say that God does nothave to stock the mind with a series of discrete items; on the contrary, inendowing a mind with an innate idea of extension, he ipso facto endows it withinnate ideas of all possible geometrical figures. Thus there is no threat to thesimplicity of the divine ways. It may be objected that Leibniz is the victim ofhis reductionism here. From the fact that the idea of x entails the idea of y, itdoes not follow that John’s having the idea of x entails that he has the idea of y;consider the case where y is a very unobvious consequence of x. The objectionmay be sound, and it may be fatal to attempts to reduce logic to psychology.But it seems that it would leave Leibniz unimpressed, for in the New Essays hedoes appear to hold that a person has at least implicit or potential knowledgeof all the logical consequences of his ideas (NE, I.1, A.VI.vi; RB 77). Indeed,Leibniz surely must say this, given his commitment to analysing talk aboutideas in terms of talk about people’s psychological dispositions.

When Malebranche’s objection is construed in terms of perceptions, how-ever, such a line of defence is no longer available. Although Leibniz reduces logicto psychology, he still allows us to say that ideas are linked by relations of logicalentailment. But thoughts and perceptions are clearly not in this category; theyare discrete psychological items which occur at particular times. At this level ofanalysis,Malebranche’s objection seems to have some bite to it. For the purposesof arguing against Locke, Leibniz may write as if only some perceptions areinnate, but when he is doing deep metaphysics he advances a much strongerthesis; he holds that in a sense all perceptions are innate. According to Leibniz, itis of the very nature of an individual substance that at everymoment it perceivesthe whole universe according to its point of view; it follows from this that ateverymoment in its history themind is in an infinitely complex perceptual state.What generates this complexity is of course the doctrine of unconscious per-ceptions. Thus Leibniz has metaphysical reasons of his own for holding that amind has an infinitely large stock of innate perceptions.Leibniz answers Malebranche here on the principle that attack is the best

means of defence. According to Leibniz, it is Malebranche’s occasionalismwhich violates the simplicity of the divine ways. However unfairly, Leibnizfrequently objects that occasionalism involves a perpetual miracle; it invokes



God as a deus ex machina who intervenes constantly to suspend the laws ofnature (G IV 476; L 457). By contrast, the doctrine of pre-established harmonyfares much better; it is an elegant hypothesis which is worthy of the divinewisdom. In creating minds, God endows them with their own laws or pro-grams, and it is by virtue of the programs alone that their subsequent statesevolve in harmony with those of other substances (G IV 476; L 457). Thus Godhas no need to interfere with the laws of nature. The doctrine of pre-estab-lished harmony is indeed the simplest of intelligible hypotheses concerningthe union of mind and body.

(iv) The doctrine of pre-established harmony also provides the answer toMalebranche’s final objection. Malebranche had objected that it is impossibleto understand how the mind could make the right selections from its stock ofinnate ideas. It would seem that it must be a cosmic accident if I regularlyperceive the sun as a small round disc when my body is affected in theappropriate way. Leibniz meets this objection by denying that the mindneeds to choose among its innate ideas. At the time of his second reading ofThe Search After Truth Leibniz had observed that the production of our ideasdoes not always depend on our will (MLR 185). In other words, to say that weare the source of our perceptual states does not imply that they depend on ourconscious will. The theory of unconscious perceptions explains how this can beso: we have a tendency or ‘appetition’ to new perceptual states, even though weare not aware of it. Thus, according to the doctrine of pre-established harmonythe mind is so initially programmed that its perceptions evolve in harmonywith those of other substances.

The controversy we have examined in this essay is confessedly a reconstruc-tion; it has been assembled from many places in the writings of both philoso-phers. There is nowork such as theNewEssayswhich serves as the forum for theLeibniz–Malebranche debate over innate ideas. But in some ways the recon-structed controversy is more illuminating than the famous debate betweenLeibniz and Locke; for Malebranche’s objections raise fundamental questionsabout the relationship between logic and psychology, concepts and thoughts.And by reconstructing his replies we can see how Leibniz seeks to avoid crudepsychologism while denying the existence of abstract entities. From the NewEssays alone it is easy to come away with the impression that Leibniz is preparedto accept ideas and dispositions in an unreduced form. But we have seen thatthis impression is incorrect. On the contrary, Leibniz adopts a strategy fordefending innate ideas which is doubly reductionist: ideas are reduced todispositions, and dispositions in turn are reduced to unconscious perceptions.It takes the Platonist Malebranche to track Leibniz to his nominalist lair.20

20 I am grateful to Henry Allison and Jonathan Bennett for their helpful comments on earlierdrafts of this essay.



8

Leibniz and the Excellence of Minds

It is now generally agreed that Leibniz’s Discourse on Metaphysics is in largemeasure a response to Malebranche.1 In the Discourse Leibniz indicates hisdisagreement with Malebranche early on in a section entitled: ‘Against thosewho think God could have done things better’ (G II 12; WF 55); Leibnizresponds to Malebranche’s thesis that God could have created a better worldby teaching that the actual world is the best of all possible worlds. But in thiswork Leibniz does not merely target the main themes of Malebranche’s the-odicy; he also criticizes the famous doctrines of occasionalism and vision inGod.Indeed, it is in the course of criticizing these doctrines that Leibniz expoundssome of the positive theories for which theDiscourse is celebrated. In oppositionto Malebranche’s occasionalism Leibniz advances what later came to be knownas the system of pre-established harmony; in opposition to Malebranche’sdoctrine of vision in God Leibniz advances his theory of innate ideas.Leibniz’s critique of the doctrines of occasionalism and vision in God in the

Discourse can hardly be missed by any reader familiar with his philosophy.Nonetheless, it is tempting to suppose that Leibniz’s critique of these meta-physical and epistemological theories is largely unrelated to his quarrel withMalebranche’s theodicy that is announced early on in the work. In this essayI argue that this view of the work is mistaken; Leibniz’s opposition to Male-branche in the work is systematic. His chief aim in the work is to establishan anti-Malebranchian thesis in theodicy; this is the thesis that the worldwhich God creates is the one in which the happiness of minds is maximal. To

1 ‘Leibniz admired much in Malebranche’s style of philosophical writing and the Discourseis influenced by the form, style, and content of Malebranche’s Treatise of Nature and Grace’, inR.N.D. Martin and S. Brown (eds. and trans.), G.W. Leibniz: Discourse on Metaphysics andRelated Writings (Manchester: Manchester University Press, 1988), p. 1; ‘Malebranche’s Traité[de la nature et de la grace] seems to be the main target of the essay.’ AG 36, n. 70; ‘The essay wascomposed at a time when Leibniz had been following with interest, and real or pretendeddisapproval, the extended quarrel between Arnauld and Malebranche, and he may have thoughtof himself as able to effect a compromise. In any case, in writing it he drew on his knowledge ofMalebranche’s Recherche de la verité (1674) and of his Traité de la nature et de la grace (1680)’,Catherine Wilson, Leibniz’s Metaphysics: A Historical and Comparative Study (Manchester:Manchester University Press, 1989), p. 81.


establish this thesis Leibniz seeks to show that minds are indeed worthy ofbeing the chief object of God’s concern; they are excellent in the sense thatthey are endowed with perfections that are denied to other created beings. Theproof of this thesis involves Leibniz in a critique of Malebranche’s metaphysicsand epistemology, for the doctrines of occasionalism and vision in God aretotally opposed to the Leibnizian conception of the excellence of minds; if thedoctrines of occasionalism and vision in God were true, minds could not beexcellent in Leibniz’s sense.

To view the Discourse on Metaphysics as a systematic refutation of Male-branche is to adopt a perspective on the workwhich is wholly different from thatwhich dominated Leibniz studies for much of the last century. Traditionally, theDiscourse on Metaphysics has been seen as one of the canonical expressions ofLeibniz’s attempt to derive his metaphysics from his logic; in the course of a fewparagraphs Leibniz is supposed to deduce his principal claims about substancesfrom his concept-containment theory of truth. It is no part of the aim of thisessay to attack this ‘logicist’ interpretation directly; indeed, there is much in thisinterpretation which is at least formally compatible with the present approach.Nonetheless, as a reading of theDiscourse the ‘logicist’ approach suffers from theclear weakness that it is forced to treat much of the work as irrelevant, or at leastperipheral, to the central argument; indeed, on this approach it is impossible tounderstand why the work takes the form that it does. In the present essay I seekto show that the Discourse on Metaphysics is in fact a highly organized andunified work which is dominated by a coherent strategy of argument.

I

Although the Discourse on Metaphysics is a critique of Malebranche’s philoso-phy, there is no doubt that Leibniz found much to admire in the work of hiscontemporary. As Donald Rutherford says, ‘Leibniz clearly drew considerableinspiration from his reading of the Treatise of Nature and Grace.’2 In the areaof theodicy, Leibniz and Malebranche are to some extent kindred spirits: bothphilosophers mount highly ambitious attempts to defend God’s characterbefore the bar of reason against the charge of injustice. Their theodicies aresimilar not just in their themes but in some of the apparatus which theyemploy: Malebranche, no less than Leibniz, for instance, appeals to the idea ofpossible worlds to explain God’s creation. Indeed, from a certain perspective,the differences between the two theodicies can seem relatively inconsequential.Malebranche’s God chooses the world which is most perfect, not absolutely,

2 D. Rutherford, ‘Malebranche’s Theodicy’, in S. Nadler (ed.), The Cambridge Companion toMalebranche, p. 185n.



but relative to the non-negotiable side-constraint that his ways must honour him;this condition is to be understood in terms of the fecundity and simplicity of thelaws which he chooses. Leibniz, by contrast, proposes that these values beincorporated into the criteria of perfection for possible worlds. By means ofthis amendment Leibniz is able to rescue the thesis that God creates the best of allpossible worlds absolutely or without qualification. At least in certain accommo-dationist moods, Leibniz himself encourages the idea that he is simply proposinga modest revision to Malebranche’s theodicy. In the Theodicy, for instance,Leibniz stresses the similarity between his position and that of Malebranche:

The ways of God are those most simple and uniform: for he chooses rules thatleast restrict one another. They are also the most productive in proportion to thesimplicity of ways and means . . .One may indeed reduce these two conditions ofsimplicity and productivity to a single advantage, which is to produce as muchperfection as is possible: thus Father Malebranche’s system in this point amountsto the same as mine.

(II 208, G VI 241; H 257)

From a passage like this it is easy to come away with the impression thatLeibniz’s theodicy is a minor variation on a theme by Malebranche.Arguably, however, the differences between the two theodicies are more

radical than this, and for the purposes of understanding the Discourse onMetaphysics it is the differences which are important. One of the central themesof Malebranche’s theodicy is that, since God acts solely for the sake of his ownglory, his actions must bear the mark of his attributes; in particular, they mustexpress his attribute of wisdom. In an addition to the Treatise of Nature andGraceMalebranche explains that God’s wisdom is more important to him thanhis work (OCM V 47). In the Theodicy Leibniz may encourage us to supposethat the dispute between Malebranche and himself is entirely about the way inwhich the good should be defined, but this is really misleading. For as StevenNadler says, Malebranche’s God is not trying to produce as much good aspossible.3 Indeed, Nadler suggests that it is illuminating to bring out thedifference between the two conceptions of God by means of an analogy withmoral theory. ‘One can almost say that Malebranche’s God is the deontologistfor whom a particular valuemust be pursued nomatter what the consequences;Leibniz’s God, by contrast, is a consequentialist who chooses means in order toproduce as much good as possible.’4 The analogy can even be pushed a littlefurther: in the Discourse on Metaphysics Leibniz is concerned to establish,against Malebranche, that the actual world is the one in which the happinessof minds is at a maximum.

3 S. Nadler, ‘Choosing a Theodicy: The Leibniz-Malebranche-Arnauld Connection’, Journalof the History of Ideas 55 (1994), 581.

4 Nadler, ‘Choosing a Theodicy’, p. 581.


Leibniz and the Excellence of Minds 123

There is no doubt, then, that Leibniz’s God is guided by goals in creationwhich are foreign to those of the Malebranchian God. But though Leibniz goesso far as to claim that God makes the happiness of minds his chief purpose increation, it would be a mistake to infer from this that he does not act for thesake of his glory. On the contrary, Leibniz seeks to insist, against Malebranche,that acting for the sake of his glory requires God to create minds which aredeserving of his special care:

This great nobility of nature, which brings minds as near to the Divinity as ispossible for mere created things, means that God derives infinitely more gloryfrom minds than from all other beings, or rather, that other beings only providethe material for minds to glorify him.

(DM 36, G IV 462; WF 88)

Perhaps Leibniz would not go so far as to say with Malebranche that God canact only for the sake of his glory (OCM V 12); for this strong thesis seemsinconsistent with the claim that the happiness of minds is God’s chief purposein creation. But it is clear that the debate between Leibniz and Malebranche isnot over the issue of whether God acts for his glory; it is rather over what thisthesis implies about the nature of God’s creation.

I I

The Discourse on Metaphysics begins and ends with theology; its first section-heading tells us that ‘God does everything in the most desirable way’ (G II 12;WF 54), and the last one that ‘Jesus Christ has revealed to men the mystery andadmirable laws of the Kingdom of Heaven and the greatness of the supremehappiness God prepares for those who love him’ (G II 14; WF 89). Between thebeginning and the conclusion the Discourse takes up some of the great themesin Leibniz’s metaphysics and epistemology; it propounds versions of thedoctrines concerning the nature of substance and causality, the mind–bodyproblem, and the nature of ideas. Yet though the Discourse covers a number ofseemingly distinct topics, it is a highly organized work which is informed by aclearly defined strategy of argument. This argumentative strategy can beexplained by saying that Leibniz moves through a series of theses:

(1) God is an absolutely perfect being.(2) God creates the best of all possible worlds.(3) The actual world is the one in which the happiness of minds is at a

maximum.

What is striking here is that Leibniz moves from a thesis which Malebrancheaccepts to two which he would deny; for though, as we have seen, Malebranchewould accept a qualified version of (2), he certainly cannot accept it as it stands.



In the Discourse on Metaphysics Leibniz devotes rather little space to theargument from (1) to (2); in one way this is curious, for the argument raisestroublesome issues concerning the contingency of propositions about the rela-tionship between God’s character and his actions.5 By contrast, in theDiscourseit is themove from (2) to (3) which really occupies Leibniz’s attention. Instead ofbridging the gap by definitionalfiat, Leibniz appeals to the excellence ofminds inorder to establish (3): it is the fact of their preeminence among created sub-stances whichmakes themworthy of God’s special concern. In other words, it istheir excellence which determines God to maximize their happiness. Signifi-cantly, this theme is stated near both the beginning and the end of theDiscourse:

Now the most perfect of all beings, and which occupy the least space, in otherwords, which obstruct each other the least are minds whose perfections arevirtues. That is why there is no doubt that the happiness of minds is the mainaim of God, which he carries out as far as the general harmony will permit. Wewill say more about this later.

(DM 5, G IV 430; WF 57)

Leibniz keeps the promise in the penultimate paragraph of the Discourse onMetaphysics:

Minds are actually the most perfectible of all substances . . . It manifestly followsfrom this that God, who always aims at the greatest perfection in general, will havethe most care for minds and will give them (not only in general but also to each onein particular) the highest level of perfection that the universal harmony will allow.

(DM 36, G IV 461; WF 88)

Simplifying a little, one might reconstruct the argument as follows:

(1) Minds are the substances most capable of perfection.(2) God aims at the greatest perfection in general.(3) If God aims at the greatest perfection in general, he will take the greatest

care of the substances most capable of perfection.(4) Therefore, God will take the greatest care of the substances most

capable of perfection.(5) Therefore, God will take the greatest care of minds.

From this Leibniz infers that God will give to minds the greatest possiblehappiness that harmony permits:

This concern [i.e. of entering into a society with us like a prince with his subjects]is so dear to him that the happy and flourishing state of his empire, which consists

5 One problem is whether the conditional proposition ‘If God is good, he creates the best of allpossible worlds’ is a necessary truth. For a discussion of this issue see R.M. Adams, ‘Must GodCreate the Best?’, Philosophical Review 81 (1972), 317–32; J. Bennett, A Study of Spinoza’s Ethics(Cambridge: Cambridge University Press, 1984), pp. 115–16.



in the greatest possible happiness of the inhabitants, becomes the most supremeof his laws. For happiness is to people what perfection is to beings. And if the firstprinciple of the existence of the physical world is the decision to give it thegreatest possible perfection, then the first aim for the existence of the moral worldor City of God, which is the noblest part of the universe, must be to spread in itthe greatest possible happiness.

(DM 36, G IV 462; WF 88)

Thus God creates the world in which the happiness of minds is at a maximum.Much of the intervening discussion in the sections between these two para-graphs is devoted to establishing the truth of (1); in other words, minds have adegree of perfection which is denied to other substances.

One problem of understanding Leibniz’s strategy of argument is that hetends to give apparently different accounts of the quality of minds whichmakes them the object of God’s special consideration. The argument above (inDM 36) turns on the premise that minds are the most perfectible of sub-stances, or the substances most capable of perfection; elsewhere Leibnizadvances the seemingly stronger thesis that minds are the most perfect ofsubstances (DM 5, G IV 430; WF 57). The difference between these twoformulations should not trouble us unduly. When Leibniz says that mindsare the most perfectible of substances, he does not mean to assert that theymerely have the potential to excel other substances in perfection; he surelydoes not wish to deny that at every stage in their history minds are pre-eminent among created substances. Rather, Leibniz is simply drawing ourattention to the fact that minds have a capacity for developing in perfectionwhich is denied to other substances. As we shall see, knowledge is at least oneof the perfections of minds, and in respect to this perfection, minds are capableof indefinite development.6 By contrast, knowledge (in the strict sense) isdenied to lower substances such as animals and plants.

A further problem posed by Leibniz’s argumentative strategy in the Dis-course concerns the focus of his quarrel with Malebranche regarding theexcellence of minds. Although the general lines of opposition are clear, theprecise nature of the disagreement needs to be treated with some care. It mightbe said that Malebranche could be brought to accede to the letter of Leibniz’sformula that minds are the most perfectible or at least the most perfect ofsubstances. For Malebranche is committed to the Augustinian thesis thatthought is nobler in nature than matter, whose essence, of course, is consti-tuted by the attribute of extension (SAT, Preface, OCM I 9; LO xix). And, forMalebranche, whose official ontology is Cartesian, there are only two kindsof created substances: mind and matter. Nonetheless, despite the fact thatMalebranche might not quarrel with the letter of Leibniz’s formula, it is clear

6 See D. Rutherford, Leibniz and the Rational Order of Nature (Cambridge: CambridgeUniversity Press, 1995), p. 52.



that there is a substantive disagreement between the two philosophers over theissue of the excellence of minds. For Leibniz holds that minds are endowedwith god-like perfections which Malebranche cannot grant. By virtue of hisoccasionalism Malebranche is committed to denying that minds have genuinecausal powers; although, especially towards the end of his career, whentreating human freedom, Malebranche concedes that in a sense minds canbe real causes, he consistently denies that they are efficacious causes capable ofbringing about real changes either in themselves or other substances.7 Thislack of genuine causal efficacy is common to created minds and to matter. Andby virtue of his doctrine of vision in God Malebranche denies that minds haveany genuine cognitive resources of their own. Malebranche does not of coursedeny that created minds are capable of achieving knowledge; indeed, they arecapable of achieving a priori knowledge as in geometry. But he does deny thathuman minds can draw this knowledge out of themselves by, for instance,attending to innate ideas or activating innate dispositions (DMR III.4, OCMXII 64–5; JS 32–3). Rather, for Malebranche, minds are dependent for know-ledge on divine illumination; that is, they must be related to ideas in Godwhich he displays to them. In respect of both causal and cognitive resources,Malebranchian minds are lacking in the perfections which Leibniz ascribes tominds; although, in places, Malebranche seeks to do justice to the biblicalteaching that minds are made in the image of God, he could not say, withLeibniz, that minds are ‘little gods’ or ‘children of God’s house’ (DM 36, G IV461; WF 88). As we have already seen in another context, characteristicallyLeibniz seeks to accommodate Malebranchian insights wherever he can; inparticular, he tries to offer a sympathetic re-interpretation of the doctrine ofdivine illumination in terms of his own philosophical commitments. None-theless, it is also true to say that Leibniz seeks to show that minds are indeedexcellent in a sense which entails the falsity of occasionalism and vision in Godas Malebranche understands those doctrines. This is the main, if not theexclusive, theme of sections 8–29 of the Discourse on Metaphysics.

I I I

Many readers of the Discourse on Metaphysics have felt that section 8 marksa new stage in the overall argument of the work. Indeed, advocates of the

7 See E. Kremer, ‘Malebranche on Human Freedom’, in S. Nadler (ed.), The CambridgeCompanion to Malebranche, pp. 201–14; R.C. Sleigh Jr, V. Chappell, and M. Della Rocca,‘Determinism and Human Freedom’, in D. Garber and M. Ayers (eds.), The Cambridge Historyof Seventeenth-Century Philosophy (Cambridge: Cambridge University Press, 1998), vol. 2,pp. 1243–4.



so-called ‘logicist’ thesis have sometimes even been tempted to claim that it isin this section that the philosophy of the work really begins; for it is here thatLeibniz derives the metaphysical consequences of his thesis that individualsubstances have complete concepts (a thesis which is in turn derived from theconcept-containment theory of truth).8 The belief that section 8 introduces anew stage in theDiscourse is surely justified, but any adequate account of its placein the structure of the work must satisfy two conditions. First, such an accountmust explainwhy at this stage Leibniz addresses the issue towhich occasionalismis proposed as a solution; this is the issue of distinguishing between the actions ofGod and creatures, and as Leibniz himself states, it is in order to resolve this issuethat he needs to explain the nature of individual substances. Secondly, a satis-factory account of the place of this section in theDiscoursemust explain how thiscritique of occasionalism is related to the theme of theodicy that dominates theopening sections of this work. The approach proposed here satisfies these twoconditions: it insists that the solution to the problem of interpretation consists inseeing that section 8 marks the beginning of a strategy of argument for estab-lishing the excellence of minds among substances. This argument is itself in theservice of an anti-Malebranchian thesis in theodicy.

In outline, Leibniz’s strategy seems clear. First, Leibniz seeks to argue for the‘godlike’ perfections whichminds possess in common with all other substances.Next, Leibniz seeks to argue that minds have perfections which are peculiar tothemselves among substances; since these perfections are chiefly cognitive, thetransition to the second stage in the argument is marked by a correspondingchange in the focus of his critique of Malebranche; it is the vision in God ratherthan occasionalism which is now the target of attack. On the face of it, then,Leibniz is claiming that minds are the most perfect of substances; he is notclaiming that they are the only substances, or that they are the only substanceswhich are endowed with perfections. However, as we shall see, the issue is morecomplicated than this, since notoriously themain features of Leibniz’s ontologyare not yet fixed at this stage of his career; Leibniz is still uncertain as to whetherthere are any substances other than minds. But for the moment we will proceedon the assumption that minds are a distinctive class of substances.

Leibniz’s central claim about the godlike perfections of substances in gen-eral is expressed in a picturesque and striking formula: all substances aremirrors of God (DM 9, G IV 434; WF 61). This formula covers two mainclaims about the godlike perfections of minds. In the first place, all substancesmirror divine omnipotence by virtue of their causal self-sufficiency; of course,this causal self-sufficiency does not exclude the divine concurrence. It is herethat Leibniz deploys arguments from the complete concept theory to show

8 It is perhaps symptomatic of the influence of the so-called ‘logicist’ approach that in hisotherwise valuable edition G.H.R. Parkinson omits the first seven sections of the Discourse onMetaphysics. See P 18.



that no substances causally interact and that each substance is the causalsource of all its non-initial states. Secondly, all substances are mirrors of divineomniscience or infinite wisdom. From the thesis that individual substanceshave complete concepts Leibniz infers that each has marks and traces by virtueof which ‘it expresses, albeit confusedly, everything which happens in theuniverse’ (G IV 434; WF 61). Such a formula allows Leibniz to have it bothways, as it were. Leibniz can hold that, by virtue of its confused expression ofthe whole universe, every substance is a mirror of the divine perfections orinfinite wisdom. But he can also allow that, since this expression is in varyingdegrees confused, there is no danger that it will simply collapse into the divineperfection of infinite wisdom.All substances, then, aremirrors of the divine perfections of omnipotence and

omniscience, or infinite wisdom. But if this is the case, it may seem that Leibnizhasmade it difficult for himself to justify the privileged status which hewishes toaccord to minds; for minds, it seems, share with all substances the godlikeproperty of causal self-sufficiency and a kind of omniscience. But there are atleast two responses to this objection whichmay bemade on Leibniz’s behalf. Forone thing, as I have suggested, Leibniz’s fundamental ontology is not set in stoneat this stage; in the Discourse Leibniz is not yet certain that there are othersubstances thanminds. In the draft of theDiscourse Leibniz writes, for instance,that ‘minds are either the only substances there are in the world if bodiesare only true phenomena, or else at least they are the most perfect ones’(DM 35, A VI.4-B 1585; WF 87). Thus, if minds are the only substances inthe universe, Leibniz is not creating difficulties for himself by saying that allsubstances are mirrors of God. The claim that God has a special care for mindswould reduce to the thesis that God has more care for minds than for beings(such as modes, aggregates, and relations) which are less than genuinesubstances.Even if, however, Leibniz really does hold that there are substances other

than minds, there is still a way in which he can preserve their privileged status.For Leibniz wishes to say that minds are excellent or more perfect than othersubstances by virtue of their cognitive capacities; it is because of this featurethat they, unlike the lower substances, express God rather than the world.Beyond their confused omniscience with regard to the universe, minds have acapacity for self-consciousness (‘knowing what they are doing’) and forknowledge of the great truths about God and the world. Thus in the passageimmediately following the one in which Leibniz says that minds are either themost perfect of substances or the only substances, he writes:

And since the whole nature, end, virtue or function of substances is only to expressGod and the universe . . . there is no room for doubt that the substances whichexpress him with a knowledge of what they do, and which are capable of under-standing great truths about God and the universe, express him incomparably better



than those natures which are either merely animal or incapable of knowing anytruths, or which are wholly lacking in feeling and knowledge.

(DM 35, G IV 460; WF 87)

By knowing these ‘great truths’, created minds have an insight into the mind ofGod.

Minds, then, not only have perfections in common with all substances; theyare ‘excellent’ by virtue of possessing the distinctive perfection of knowledge. It isin his account of minds’ cognitive resources (especially their capacity for know-ing the eternal truths) that Leibniz moves to a critique of the Malebranchiandoctrine of vision in God; Leibniz is committed to an account of these resourcesthat is in direct opposition to the Malebranchian theory. Yet, curiously perhaps,Leibniz has not finished with his critique of occasionalism; indeed, he deploys ananti-occasionalist thesis to argue for the falsity of the doctrine of vision in God:

I do not share the opinion of some able philosophers [e.g. Malebranche] who seemto maintain that our ideas themselves are not in any way in us, but are in God. Inmy view this comes from not yet having sufficiently thought about what we haveexplained here about substances, and about the total extent and independence ofour soul, which mean that it contains everything that happens to it, and expressesGod, and with him all possible and actual beings, as an effect expresses its cause.

(DM 29, G IV 453–4; WF 80)

Thus Leibniz seems to be appealing to the thesis of substantial causal self-sufficiency to argue against the Malebranchian thesis that we have no ideas ofour own.

It is important to understand how this argument against vision in God issupposed to go. Recall that Leibniz’s doctrine of the causal self-sufficiency ofsubstances involves both a negative and a positive thesis. The negative thesis isthat no two created substances causally interact with each other; the positivethesis is that each created substance is the causal source of all its non-initialstates. Leibniz cannot of course appeal to his negative thesis to argue for theconclusion that minds think by means of their own ideas, and are thus in thissense cognitively resourceful. For the negative metaphysical thesis, as Leibnizunderstands it, is entirely consistent with the claim that God, and God alone,acts on created substances; indeed, in theDiscourse Leibniz is explicit that he iscommitted to this claim. Thus the negative thesis has no tendency to refute theclaim that minds achieve knowledge only by being related to the ideas in thedivine understanding which God displays to us. Leibniz is of course entitled toappeal to the negative metaphysical thesis to refute the doctrine of the tabularasa; in fact, he does just this in defending his own theory of innate ideas:

This fits in with my principles, for nothing naturally enters our minds fromoutside, and it is a bad habit of ours to think of our soul as receiving messengerspecies, or as if it had doors and windows.

(DM 26, G IV 451; WF 78)



For Leibniz, the empiricist doctrine of the tabula rasa, on which the finger ofexperience writes, assumes the existence of causal interaction between createdsubstances; by contrast, the theory of vision in God makes no such objection-able assumption.Leibniz, then, must be appealing to his positive metaphysical thesis in order

to refute the Malebranchian metaphysical thesis that we have no ideas of ourown; in particular, he is relying on his positive doctrines that substances ingeneral (and a fortiori minds) are not only causal sources of all their non-initialstates but also express the entire universe. But to say this is not to say that theconfused kind of omniscience which is common to all substances is that whichconstitutes knowledge of the ‘great truths’ in minds. For the exalted kind ofknowledge that minds enjoy involves or requires the possession of ideas, andideas, according to the Discourse, it seems, are dispositional properties; theysupervene on unconscious perceptual states or expressions in rather the sameway that fragility, for example, supervenes on physical microstructures.9 Whenthese cognitive dispositions which constitute ideas are actualized, the result isoccurrent mental states (for example, occurrent understanding of the eternaltruths). This picture does not commit Leibniz to saying that all substances haveideas which supervene on their unconscious expressions. To suppose thatLeibniz was committed to this thesis would be like supposing that a recognitionof fragility as a dispositional property which supervenes on microstructuralproperties commits one to holding that all bodies are fragile; it is only onunconscious expressions that ideas supervene. Thus Leibniz’s two claims thatthe knowledge that minds possess depends on having ideas and that ideas arecognitive dispositions which supervene on unconscious mental states areentirely consistent with his general thesis that minds enjoy a privileged statusby virtue of their capacity for knowing the ‘great truths’.

IV

In opposition to Malebranche, then, Leibniz is committed to what he calls ‘theexcellence of minds’; not only are they causally resourceful, in common withother substances, but they are also cognitively resourceful. According toLeibniz, the excellence of minds is such that it makes them worthy of specialconsideration by God; this special consideration takes the form of makingtheir greatest possible happiness his supreme law. But though so much is clear,there remains a problem of how exactly the excellence or perfection of minds

9 Here I am indebted to C.D. Broad, Leibniz: An Introduction (Cambridge: CambridgeUniversity Press, 1975), pp. 134–5; B. Mates, The Philosophy of Leibniz: Metaphysics andLanguage (New York and Oxford: Oxford University Press, 1986), pp. 49–50, 175.



is related to their happiness.10 To make progress with this issue we need to saymore about what it is that makes minds the most perfect of substances. Even inthe Discourse there are apparently different strands in Leibniz’s thought onthis issue.

As we have seen, a central theme of the Discourse is that the particularexcellence of minds is to be understood in terms of their cognitive capacities. Inthe section which is actually entitled ‘The excellence of minds’ Leibniz explainsthat what makes minds express God incomparably better than lower natures isthe fact that they know what they are doing and are capable of knowing greattruths about God and the universe. Elsewhere Leibniz expands the suggestion inthe last phrase that the knowledge which minds possess divides into two parts:

One cannot love God without knowing his perfections, or his beauty. And sincewe can know him only in his emanations, there are two means of seeing hisbeauty, namely in the knowledge of eternal truths (which explain [their own]reasons in themselves), and in the knowledge of the harmony of the universe (inapplying reasons to facts). That is to say, one must know the marvels of reasonand the marvels of nature.

(Gr II 580; R 84)

Now, according to at least one strand in Leibniz’s thought, pleasure super-venes on the acquisition of knowledge. Since happiness is, by definition, alasting pleasure, it would seem that happiness supervenes on the continuedacquisition of knowledge.

Even in the Discourse on Metaphysics Leibniz sketches another line ofthought according to which it is the virtues of minds that are most relevantto their happiness. In section 5 of the work, for instance, Leibniz even says thatthe perfections ofminds are their virtues (G IV 430;WF 57). The theme is takenup again towards the end of theDiscoursewhen he explains that the capacity forfriendship between God and minds is grounded in virtue; ‘only the mostvirtuous can be the most perfect friends’ (G IV 461; WF 88). Thus, in suchpassages Leibniz seems to be claiming that it is because of their virtues that Godmakes minds the object of his special consideration, and that this specialconsideration takes the form of endowing them with happiness. But of course,if this is so, then we are again confronted with the problem of understandingthe nature of the link between the perfections of minds, understood in theseterms, and the happiness which God spreads in the universe as far as he can.

One possibility is that Leibniz is envisaging the Platonic/Stoic thesis thatvirtue by itself is sufficient for happiness; a version of this thesis of course was

10 For fuller discussion of this issue in general in Leibniz’s philosophy, see D. Blumenfeld,‘Perfection and Happiness in the Best Possible World’, in N. Jolley (ed.), The CambridgeCompanion to Leibniz, ch. 12; G. Brown, ‘Leibniz and the Confluence of Worldly Goods’,Journal of the History of Philosophy 26 (1988), 571–91; Rutherford, Leibniz and the RationalOrder of Nature, ch. 3.



revived by Spinoza in Leibniz’s time in his famous proposition that blessed-ness is not the reward of virtue but virtue itself. No doubt Leibniz doessometimes conceive of the relationship between virtue and happiness inthese terms, but it is only fair to say that there are other passages in whichhe is less confident about the existence of an internal connection; he expressesthe more commonplace thought that it is only on the further assumption ofdivine rewards in an afterlife that virtue will be crowned with happiness.11

Even if Leibniz thinks that the link between virtue and happiness is an externalone of this sort, his thesis can still be unpacked in terms of the apparatus ofpossible worlds; the career of a soul after death is to be understood as part ofthe possible world in which it is located. Thus to say that God externallyrewards virtuous minds in an afterlife is to say that he chooses for creation apossible world in which virtuous minds are rewarded in this way.We have seen, then, that the excellence of minds is to be unpacked in terms

of their knowledge or virtues; on these views, happiness either supervenes onmental perfections or is an external reward for the possession of such perfec-tions. But it is only right to point out that there is a suggestion of a third strandin Leibniz’s thought according to which the perfection of minds simply is theirhappiness. In the Discourse on Metaphysics, for instance, Leibniz justifies hisclaim that the greatest possible happiness of minds becomes God’s supremelaw by saying that happiness is to persons (i.e. self-conscious minds) whatperfection is to beings (DM 36, G IV 461; WF 88). It may be objected that sucha passage stops short of identifying the happiness of persons or self-consciousminds with their perfection. However, the thesis is stated more directly andexplicitly in the paper entitled On the Ultimate Origination of Things:

Hence the world is not only the most wonderful machine, but also with regard tominds is the best commonwealth, by whose means there is bestowed on mindsthe greatest possible amount of happiness or joyfulness, and it is in this that theirphysical perfection consists.

(G VII 306; AG I53; translation modified)

Ultimately, perhaps, in the Discourse on Metaphysics Leibniz is less thanprecise about the relation between the excellence of minds and their happi-ness; there is some unclarity both about the nature of the perfections whichconstitute excellence and the nature of their connection with happiness. It isnatural perhaps to say that Leibniz offers two equivalent accounts of theexcellence of minds in the Discourse, for minds are virtuous if and only ifthey possess knowledge (i.e. knowledge of God and the universe). Such anequivalence may run into difficulties from Leibniz’s statements in othersources, but it is not contradicted by anything he says in the Discourse itself.

11 See, for instance, Du IV 296. For further discussion, see Rutherford, Leibniz and theRational Order of Nature, p. 63.



But for our present purposes the fact that Leibniz may leave some loose endsdangling in this work matters little. The important point is that in theDiscourse Leibniz affirms that the excellence of minds is in some way theground of their happiness, and that this excellence is to be understood in a waythat implies the falsity of Malebranchian doctrines.

In this essay, then, I have sought to argue for a certain reading of Leibniz’sDiscourse on Metaphysics, the first of his philosophical masterpieces. Thoserecent commentators who have stressed that the Discourse is a response toMalebranche have not gone far enough, for the work is nothing less than asystematic refutation of Malebranche’s theodicy, metaphysics, and theory ofknowledge. Leibniz’s ultimate goal in the work is to argue for the anti-Malebranchian thesis that the world which God decided to create is one inwhich the happiness of minds is at a maximum, and in pursuit of this goalLeibniz seeks to argue for a conception of the excellence of minds whichMalebranche could not possibly accept. To view the Discourse on Metaphysicsin these terms is not to deny the presence of incidental arguments which donot bear directly on the main goal. For instance, Leibniz sometimes casts hisnet more widely to attack Cartesian theses about the nature of matter and itslaws which are not distinctive of Malebranche; in other places, he targets theteachings of Spinoza. But though the goal of refuting Malebranche does notexplain every argument in the work, it provides the Discourse with its centralorganizing principle; it allows us to understand, for instance, why the workbegins by affirming divine perfections and ends by affirming that the happi-ness of minds is God’s chief aim. Since its original publication in 1846, theDiscourse on Metaphysics has always been admired as one of the best synopticexpressions of Leibniz’s philosophy, but its overriding unity of purpose hasscarcely been appreciated.



9

Leibniz and Occasionalism

What is really at issue in Leibniz’s critique of occasionalism? Ever sinceArnauld, readers have found it difficult to answer this question. At first sightthe difficulty is surprising, for superficially the battle lines between the twophilosophers seem to be clearly drawn: Malebranche holds that God is the onetrue cause, whereas Leibniz maintains that created substances are genuinecauses as well. Problems arise as soon as we encounter Leibniz’s claims to theeffect that occasionalism introduces perpetual miracles and that it appeals toGod as a deus ex machina, for even casual acquaintance with Malebranche’soccasionalism reveals that it makes heavy use of the concept of law.1 Indeed, inthe eyes of a critic such as Arnauld, the problem with occasionalism is not thatit leaves too much room for miracles, but that it leaves too little.2 It may seem,then, that Leibniz’s critique of occasionalism is directed against a straw man,and that the debate as a whole is of little philosophical interest. It is true, asI will show, that some of Leibniz’s criticisms seem misguided, but such anegative verdict on the controversy would be a mistake, for the debate betweenthe two philosophers centres on fundamental issues in metaphysics and thephilosophy of science.Perhaps the best way of approaching the debate is to begin by considering

the deep philosophical motivation for occasionalism. In a famous chapter ofThe Search After Truth entitled ‘The Most Dangerous Error in the Philosophyof the Ancients’ (6.2.3) Malebranche explains that the belief in natural causalpowers is a legacy of the Aristotelian–Scholastic tradition; such powers are in

1 Throughout this essay I restrict my discussion of occasionalism to Malebranche’s version ofthe doctrine.

2 Arnauld draws a distinction between perceptible miracles (miracles sensibles) and hiddenmiracles (miracles cachez) and claims that Malebranche’s doctrine of general volitions leaves noroom for miracles of the latter kind. ‘On the supposition of this distinction between perceptibleand hidden miracles, one easily sees how it is an untenable paradox to claim that God does notact in the order of nature by particular volitions, but only by general volitions.’ Antoine Arnauld,Réflexions philosophiques et théologiques sur le nouveau système de la nature et de la grâce(Cologne, 1695), 196. Arnauld’s example of a ‘hidden miracle’ is the case of a holy bishop who isgradually cured in response to the prayers of the faithful.


effect occult qualities which must be rejected by a philosophy founded on clearand distinct ideas. Many years ago the French scholar Lévy-Bruhl summed upthis aspect of the motivation when he remarked that ‘as a worthy successor ofDescartes, Malebranche replaces the confused Scholastic notion of cause bythe clear scientific notion of law’.3 On this view Malebranche is the naturalforerunner of Bertrand Russell, who, in a famous essay, argued that the notionof cause was the relic of an outdated conceptual scheme that had no placewithin the framework of modern science.4 If Malebranche is a forerunner ofRussell, Leibniz, by contrast, is a neo-Aristotelian who argues that the conceptof natural causality must be retained; as he puts it in the New System, ‘explan-ations must be derived from the order of secondary causes’ (G IV 483; L 457).What is at issue between the two philosophers is not just whether laws areontologically grounded in causal powers, but whether laws constitute the rockbottom in scientific explanation.

The logical relationship between these two issues might be brought out inthe following way. It is clear that one can deny that laws are ontologicallygrounded in causal powers without holding that laws are explanatorily basic:one might believe that the latter role is indeed occupied by causal powers.More controversially, it seems consistent to hold that laws are grounded incausal powers while also holding that laws are explanatorily basic. For, asI shall show hereafter, one might believe that causal powers are located at ametaphysical level below that with which science is concerned, and that theyare thus irrelevant to the project of scientific explanation.

I

Recent commentators who have written about the debate between Leibniz andoccasionalism have helpfully distinguished logically distinct strands in hiscritique. It has been observed that Leibniz’s objection that occasionalismintroduces perpetual miracles is of wholly general application; it targetsoccasionalists’ claims about the relationships between bodies no less thantheir proposed solution to the mind–body problem. But though this is Leib-niz’s most celebrated objection to occasionalism, it is not of course the onlyone; he also offers an argument that is specifically aimed at the occasionaliststance on the relationship between mind and body.5 According to this

3 Quoted in C.J. McCracken, Malebranche and British Philosophy (Oxford: Clarendon Press,1983), p. 102.

4 Bertrand Russell, ‘On the Notion of Cause’, Proceedings of the Aristotelian Society 13 (1913),1–26.

5 R.S. Woolhouse, ‘Leibniz and Occasionalism’, in Woolhouse (ed.), Metaphysics and Phil-osophy of Science in the Seventeenth and Eighteenth Centuries (Dordrecht: Kluwer, 1988), p. 176.



objection, the trouble with occasionalism is that its account of this relationshipdisturbs the laws of physics. For the purposes of this essay there is reason tobegin by addressing this strand in Leibniz’s critique, since once the weaknessesof this argument are exposed we shall see that he will be forced to fall back on asecond line of argument that brings into focus the real issue between Leibnizand occasionalism.In the Theodicy and other texts Leibniz objects that Malebranche’s occa-

sionalist account of mind–body interaction represents no real improvementover Descartes’ interactionist account; it too involves a disturbance or de-rangement of the laws of nature (G VI 136; H 156). As Woolhouse suggests,Leibniz seems to have two distinct charges in mind.6 The first is strictlyphysical: occasionalism, like Descartes’ interactionist position, is inconsistentwith the principle of the conservation of momentum. When I raise my arm,the change in the momentum of my arm must be counterbalanced by acorresponding change in momentum elsewhere, but it obviously makes nosense to suppose that this change in momentum could be located in animmaterial substance.7 The second objection is more general and metaphys-ical: occasionalism, again like Cartesian interactionism, fails to respect theprinciple that the mental and physical realms are alike causally closed: that isto say, mental events have exclusively mental causes, and physical events haveexclusively physical causes. For Leibniz, this principle implies that it is neverthe case that a physical event has mental events as either its real or occasionalcauses. By contrast, occasionalists are committed to claiming that at least somephysical events have mental events as occasional causes, and that at least somemental events have physical events as occasional causes.8

Unfortunately, for Leibniz, neither of these charges against occasionalismseems compelling. The occasionalists can meet the first objection by concedingthat, by virtue of the principle of the conservation of momentum, any changeof momentum must be counterbalanced; they must also concede that it isnonsensical to suppose that the locus of this counterbalancing could be animmaterial substance. But there is nothing in occasionalism that precludesthem from saying that the change of momentum could be counterbalancedelsewhere in the physical system. That is to say, there is no reason whyMalebranche should not offer exactly the same account as Leibniz himself of

6 Woolhouse, ‘Leibniz and Occasionalism’, p. 176.7 Woolhouse, ‘Leibniz and Occasionalism’, p. 175.8 It may be objected that Malebranche cannot accept the principle of the causal closure of the

physical realm since he is committed to the thesis that every physical event has God’s volition asits real cause, and God’s volitions are mental. The issue of divine real causality is a large topic thatI cannot explore here. However, it may be said that God is the real cause of physical events in theminimal sense that he wills the initial conditions and the laws of nature that the eventsinstantiate.


Leibniz and Occasionalism 137

how, in the case of arm-raising, the principle of the conservation of momen-tum is satisfied.

The more metaphysical objection, which turns on the general principle ofthe causal closure of the mental and physical realms, also runs into trouble.Robert Sleigh has argued that Leibniz is not well placed to defend his principleagainst occasionalism;9 in particular, with regard to the apparent action ofmind on body, he is not in a position to say that, for any physical event, there isno sequence of causes, real or occasional, that has a mental event, such as anact of volition, as one of its members. For he himself tells Arnauld: ‘Neverthe-less, one is quite right to say that my will is the cause of this movement of myarm . . . for the one expresses distinctly what the other expresses in a moreconfused way, and one must ascribe the action to the substance whoseexpression is the more distinct’ (G II 71; LA 87). If, however, Leibniz fallsback on a weaker principle to the effect that, for any physical event, there is atleast some sequence of causes, real or occasional, that has only physical eventsas its members, then again he is not well placed to refute occasionalism. For asSleigh points out, there is nothing in occasionalism per se that precludes therecognition of some such quasi-causal history. Perhaps Malebranche in factbelieved in the absence of such a quasi-causal sequence, but the problemwould not be in his occasionalism but in his ignorance of physiology.10

This is a penetrating analysis of Leibniz’s position, but it is perhaps open toLeibniz to say that his remark to Arnauld should not be taken at face value.When Leibniz says that my will is the cause of the movement of my arm, hemay be speaking with the vulgar but thinking with the learned; the concept ofexpression serves strictly as a replacement for the concept of causality ratherthan as an analysis of it. Thus Leibniz might say that he is still committed tothe principle of the strict causal closure of the physical realm; by contrast, onhis view occasionalism fails to satisfy this principle since it recognizes volitionsas at least occasional causes of some physical movements (as in the case ofarm-raising).

If Leibniz insists on this position, then it is open to the occasionalist to replyby emphasizing just how weak is the conception of an occasional cause.Indeed, Malebranche could say that talk of occasional causes commits himto no claims about mental or physical events as metaphysically real causes; it isthus incapable of constituting any sort of challenge to Leibniz’s principle ofcausal closure. It is worth remembering here that Malebranche has rightlybeen seen as an ancestor of Hume, and the doctrine of occasional causes reallyamounts to no more than recognition of what Hume was to call constant

9 Robert C. Sleigh, Leibniz and Arnauld: A Commentary on Their Correspondence (NewHaven: Yale University Press, 1990), pp. 166–7.

10 Sleigh, Leibniz and Arnauld, p. 167.



conjunction.11 To say that events of type A are occasional causes of events oftype B is to say that events of type A are regularly followed by events of type B.Thus, Leibniz cannot deny that volition is an occasional cause of arm-raisingwithout denying the existence of incontestable empirical regularities. It is truethat Malebranche might wish to challenge Leibniz’s principle of the causalclosure of the mental and physical realms. But his basis for doing so, I believe,is not that he is committed to the existence of at least quasi-causes thatstraddle the two realms; it is rather that he wishes to insist that the wholecategory of natural causality is an outdated one that has no place in ontologyor the philosophy of science. As Lévy-Bruhl suggests, the category calls forreplacement by the more precise concept of law.

II

To discover the heart of the debate between Leibniz and occasionalism onemust turn to his notorious charge that occasionalism involves perpetualmiracles; as I will show, it is here that we find the real controversy over theissue of whether laws or causal powers are explanatorily and ontologicallybasic. When Leibniz charged occasionalism with reintroducing perpetualmiracles, Bayle expressed his puzzlement in a note to the article ‘Rorarius’ inthis famous Dictionary:

The reason why this clever man finds the Cartesian system not to his taste seemsto me to be based on a false supposition; it cannot be said that the system ofoccasional causes, with its reciprocal dependence of body and soul, makes theactions of God into the miraculous interventions of a deus ex machina. For sinceGod intervenes between them only according to general laws, in doing so henever acts extraordinarily.

(WF 197)12

Today it is natural for us to share Bayle’s sense of puzzlement, for we are likelyto agree with his implicit conception of a miracle as a suspension of a law ofnature; moreover, as we have seen, even a superficial acquaintance withoccasionalism reveals, as Bayle says, that its universe is governed by laws.Thus it seems that Bayle must be right to say that Leibniz wholly misses themark in charging occasionalism with perpetual miracles. Yet such a reactionwould reveal a misunderstanding of Leibniz, for, according to his definition,he is justified. For Leibniz, a miracle is not to be defined in terms of a

11 For a valuable account of Hume’s relationship to Malebranche, see McCracken, Male-branche and British Philosophy, pp. 254–90. See also chapter 17 in this volume.

12 The original text is found in the Dictionnaire historique et critique (Amsterdam, 1696–97),vol. 1, p. 967.



suspension of a law of nature; it is to be defined rather as an event that exceedsthe causal powers of created things (G IV 520; WF 205). On this definition it istrivially true that, according to occasionalism, in the universe all events aremiraculous, for if genuine causal powers are at issue, then creatures have nosuch causal powers.13

Leibniz’s insistence that a miracle is correctly defined as an event thatexceeds the causal powers of creatures suggests a possible strategy for replyingto Bayle. Consistently with his definition, Leibniz could have conceded thatoccasionalism recognizes the existence of laws of nature; he could nonethelesshave insisted that, given his definition of a miracle, such a recognition has nobearing on the issue of perpetual miracles. Superficially it may seem thatLeibniz is indeed tempted by this strategy, for he tells Bayle:

Let us see, however, whether the system of occasional causes really doesn’t involvea perpetual miracle. Here it is said that it does not, because the system holds thatGod acts only according to general laws. I agree that he does, but on my view thatis not enough to remove miracles.

(G IV 520; WF 205)

But despite appearances, this is not the strategy that Leibniz chooses to adopt.Leibniz does not deny that occasionalism recognizes the existence of laws orrules in the sense of divinely ordained regularities, but he does deny that suchregularities constitute genuine laws of nature. With regard to the occasionalistlaws of the union of body and soul, Leibniz writes, in some comments onLamy: ‘But I do not at all agree that such a rule would be a law of nature, northat the general laws of nature are wholly arbitrary’ (G IV 594). And, asLeibniz goes on to say, all miracles are exceptions to the laws of nature, evenif they are not to be defined in these terms (G IV 594–5). Indeed, it seems thatLeibniz would recognize equivalence here: x is beyond the causal powers ofcreatures just in case x is an exception to a law of nature.

Leibniz’s position, then, is not that the occasionalists recognize the existenceof laws of nature and that this is irrelevant to the issue of miracles; it is ratherthat the occasionalists do not, strictly speaking, recognize the existence of lawsof nature at all. This has led some commentators to suggest that the real issuebetween Leibniz and occasionalism is the proper conception of a law of nature.Donald Rutherford, for instance, says that Leibniz wants to insist againstMalebranche that laws of nature are laws of the nature of things.14 There isno doubt that Leibniz does wish to uphold such a claim, but it remains aquestion how it should be interpreted. When the claim is properly construed,I believe, we shall see that the fundamental issue between Leibniz and

13 See Sleigh, Leibniz and Arnauld, p. 162.14 Donald Rutherford, ‘Natures, Laws, and Miracles: The Roots of Leibniz’s Critique of

Occasionalism’, in Nadler (ed.), Causation in Early Modern Philosophy, p. 145.



Malebranche is whether it is causes or laws that have ontological and explana-tory primacy. It is Leibniz’s commitment to the primacy of causes that surfacesin his insistence that being an exception to a law of nature is only a derivativetruth about miracles; it does not constitute their essence.One obvious difficulty in understanding Leibniz’s critique of occasionalism

on this score lies in knowing what he means by ‘natures’. Rutherford seems toassume that the natures of things are equivalent to their essences;15 on thisbasis he argues that, according to Leibniz, for a generalization to qualify as alaw it is not sufficient that it should describe a regularity willed by God; ‘itmust, in addition, be possible to conceive of the effects it describes as “explic-able modifications” of the natures of their subject’.16 According to Rutherford,the trouble with the occasionalist concept of a law from Leibniz’s standpoint isthat it makes no provision for the intelligibility of the created world.17 In thisconnection, and elsewhere, Rutherford speaks of what he calls Leibniz’scommitment to the Principle of Intelligibility.Rutherford’s assumption that the natures of things are equivalent to their

essences is not an unreasonable one; such an equivalence does indeed seem tohold in the writings of Descartes and Spinoza, for example. Moreover, thereare some passages that suggest that Leibniz himself subscribes to such anequivalence. In the Preface to the New Essays, for instance, Leibniz mounts acritique of Locke’s ‘thinking–matter’ hypothesis that is in many ways reminis-cent of his case against occasionalism:

But to explain myself more distinctly: it must be borne in mind above all that themodifications which can occur to a single subject naturally and without miraclesmust arise from limitations and variations of a real genus—i.e., of a constantabsolute inherent nature. For that is how philosophers distinguish themodes of anabsolute being from that being itself; just as we know that size, shape, and motionare obviously limitations and variations of corporeal nature (for it is plain how alimited extension yields shapes, and that changes occurring to it are nothing butmotion) . . . So within the order of nature (miracles apart) it is not at God’sarbitrary discretion to attach this or that quality haphazardly to substances. Hewill never give them any which are not natural to them, that is, which cannot arisefrom their nature as explicable modifications.

(NE Preface, A VI.vi; RB 66)

A striking feature of this passage is its strongly Cartesian flavour. For theCartesians, of course, the essence or nature of matter is constituted by

15 Rutherford remarks that the Principle of Sufficient Reason requires that ‘within the “orderof nature” it is not enough that there simply be some reason for anything to happen as it does; inaddition, there must be what Leibniz calls a “natural reason”: a reason that displays the effect inquestion as following in an intelligible manner from the nature or essence of some created being’.‘Natures, Laws, and Miracles’, p. 142.

16 Rutherford, ‘Natures, Laws, and Miracles’, p. 145.17 Rutherford, ‘Natures, Laws, and Miracles’, p. 147.



extension, its principal attribute, and any (non-miraculous) property of matteris a modification or way of being of this attribute; thus being circular orrevolving is supposed to be clearly a way of being extended. Now Leibnizdoes not subscribe to the Cartesian principle that the essence of matter isconstituted by a principal attribute, extension; but he seems to be accepting themore general principle that any non-miraculous property of matter must be amodification of its essence or nature. Thus, for the purpose of arguing againstLocke, Leibniz seems to be helping himself to a Cartesian identification ofnature and essence.

Yet it is more characteristic of Leibniz, in his attacks on occasionalism, toseek to draw a distinction between the concepts of nature and essence. In the‘Conversation between Philarète and Ariste’, as Sleigh notes, Leibniz remarks:‘One can distinguish three degrees among predicates: the essential, the natural,and what is simply accidental’ (G VI 584; L 621).18 And in the anti-occasional-ist work De Ipsa Natura Leibniz clearly implies a distinction between theconcepts of nature and essence, even if he does not explicitly state it:

If, on the other hand, the law God decreed has in fact left some trace of itselfimpressed upon things—if things have been formed by the command in such away that they are capable of fulfilling the meaning of the command—then it mustbe admitted that things have been given a certain ability, a form or force (such aswe usually call a ‘nature’) from which the series of phenomena follows inaccordance with the dictates of the original command.

(G IV 507; WF 213)

Here the nature of a thing is equated with a force, and the force of a thing canhardly be identical with an essence: on this view, natures are rather thosecausal powers or forces which the occasionalists are committed to denying. AsVailati remarks, a crucial difference between essences and natures is that, forLeibniz, God finds essences in his understanding, whereas through his will heis responsible for the natures of created things.19 Thus, when Leibniz says thatlaws must be grounded in the natures of things, he is claiming in thesecontexts that laws must be grounded in causal powers.

Against occasionalism, then, Leibniz maintains that a law or rule is not trulya law of nature unless it is grounded in the nature, that is, the causal powers orforces of created substances. Although this is perhaps his central objection tooccasionalism, Leibniz is not always careful in his arguments for this thesis:indeed, his arguments suffer from two weaknesses. Consider in the first placeLeibniz’s argument that since they are not thus grounded in natures—in theLeibnizian sense—occasionalist laws of nature must be arbitrary:

18 Sleigh, Leibniz and Arnauld, p. 78.19 Ezio Vailati, Leibniz and Clarke: A Study of their Correspondence (New York: Oxford

University Press, 1997), p. 149.



But I do not agree that such a rule would be a law of nature, nor that the generallaws of nature are purely arbitrary. It is not an absolute necessity that has led Godto establish them; however, he has been led to them by some reason consistentwith his supreme wisdom and by a certain conformity with the natures of things.

(G IV 594)

In this passage Leibniz is making an entirely familiar point: his own positionon the laws of nature occupies a middle ground between Spinozist necessitar-ianism on the one hand and Cartesian pure voluntarism on the other. But inseeking to show that occasionalists are committed to an objectionable Carte-sian voluntarism, Leibniz seems guilty of a non-sequitur. From the fact thatoccasionalist laws of nature are not grounded in natures or causal powers, inthe Leibnizian sense, it does not follow that they are thereby condemned to bepurely arbitrary.20 To avoid this charge it is sufficient that there be reasons forGod’s choice of the laws that are instantiated in our world, and Malebranche isinsistent that this condition is satisfied. Indeed, Malebranche has a story to tellabout God’s choice of the laws of nature that is similar in key respects toLeibniz’s own: God’s wisdom is guided by considerations of simplicity andfecundity.21 It may indeed be true, as Leibniz says, that God establishes thelaws of nature both by some reason consistent with his wisdom and by acertain conformity or agreement with the natures of things, but in order torebut the charge of arbitrariness Malebranche is under no philosophicalpressure to concede the second of these conjuncts. Thus Leibniz is whollyunsuccessful in his attempt to tar Malebranche’s occasionalism with the brushof Cartesian voluntarism.In the second place, Leibniz seems guilty of a curious equivocation in his

critique of occasionalism. Consider Leibniz’s insistence that unless laws aregrounded in natures, they will still be perpetual miracles:

Thus it is not sufficient to avoid miracles that God makes a certain law, unless hegives creatures a nature capable of executing his orders. It is as if someone saidthat God has ordered the moon to describe freely in the air or in the ether a circlearound (à l’entour de) the globe of the earth without there being either an angel orintelligence which governs it, or solid globe which carries it, or vortex or liquidglobe which transports it, or gravity, magnetism, or any other mechanicallyexplicable cause which prevents it from swerving away from the earth or movingoff at a tangent to the circle.

(G IV 595)

20 Cf. Rutherford: ‘Malebranche would obviously contest this charge [that occasionalists arecommitted to the arbitrariness of the laws of nature]’. ‘Natures, Laws, and Miracles’, p. 145, n. 17.

21 Although there are similarities between Leibniz and Malebranche in their conceptions ofdivine wisdom, there are also important differences; for example, as Rutherford says, Leibniz isconcerned to uphold the conception of God as ‘an infinitely skilful craftsman, one who isdisposed to create the world that in and of itself contains the greatest possible perfection’.‘Natures, Laws, and Miracles’, p. 158.



In this passage the thesis that laws must be grounded in natures is treated asequivalent to the thesis that bodies must have natures capable of executingGod’s orders. But this way of explaining the thesis seems to trade on aconfusion between the prescriptive and the descriptive senses of the term‘law’. When ‘law’ is taken in the prescriptive sense, Leibniz’s critique of theoccasionalists has a certain plausibility. If I order you to run a mile in fourminutes, my order will not have much point to it unless you possess theappropriate physique: in Leibnizian terms you must have a nature or set ofcausal powers that renders you capable of executing my order. Analogously,God will not give laws, in the prescriptive sense, to his creatures unless he alsogives them a nature capable of executing his order. Clearly, in the backgroundto this discussion is the principle that ‘ought’ implies ‘can’.

When the prescriptive sense of ‘law’ is at issue, Leibniz’s thesis is plaus-ible, but it is not at all clear that it is so compelling when the term isunderstood in the descriptive sense; and of course it is natural for us to saytoday that this is the only relevant sense. Certainly it is not difficult to seehow Malebranche might reply to Leibniz’s strictures. As a good Cartesian,Malebranche will concede that bodies have an essence, extension, and thatthis essence does not logically fix or determine the laws of physics in ourworld; consistently with their essence bodies might indeed describe circularpaths instead of rectilinear ones. But it is open to Malebranche to add thatthere is no need for God to endow bodies with a nature in the Leibniziansense, over and above their essence. To bring about the observed behaviourof bodies in our world it is sufficient that God wills the laws of nature, forthe fact that these laws are the volitions of an omnipotent being guaranteesthat bodies behave in accordance with these laws. From Malebranche’sperspective the Leibnizian model of God’s activity involves a needless dupli-cation of effort on the part of the deity: not merely must he endow bodieswith natures but he must further decree laws that are somehow in conform-ity with their natures.

Leibniz’s second criticism of occasionalism thus seems to trade on anequivocation between the two senses of the term ‘law’ that we are in thehabit of distinguishing sharply today. If Leibniz was indeed unclear aboutthe distinction, he was in good company; as various scholars have shown, thehabit of thinking of the laws of nature in prescriptive terms proved surpris-ingly tenacious among early modern philosophers. Boyle, for instance,remarks that ‘nothing but an intellectual being can be properly capable ofreceiving and acting by law’.22 Somewhat similarly, Clarke observes that‘Matter [is] evidently not at all capable of any Laws or Powers whatsoeverany more than it is capable of Intelligence’, and again, that ‘dull and lifeless

22 Quoted in Catherine Wilson, ‘De Ipsa Natura: Sources of Leibniz’s Doctrine of Force,Activity, and Natural Law’, Studia Leibnitiana 19 (1987), 162.



Matter is utterly incapable of obeying any Law, or being indued with anyPowers’.23 Clearly Boyle and Clarke are thinking of a law of nature as a rule orcommand that must be understood as a condition of being followed or‘obeyed’ by any of God’s creatures. It is natural to observe that the two sensesof ‘law’ are likely to be conflated when it is common ground among philoso-phers that laws are divine decrees. Even so, though the theological frameworkmay encourage such a conflation, it does not of itself dictate it; it is stillpossible to distinguish clearly between a prescriptive divine decree, addressedto bodies, of the form: ‘Fall to the ground when unsupported’, and a descrip-tive one of the form: ‘Let it be the case that unsupported bodies fall to theground.’ Moreover, as various scholars have observed, no conceptual innov-ation on the part of early modern philosophers was required to make thedistinction, for it had already been clearly drawn by the late Scholasticphilosopher Suarez.24

Despite the apparent parallels in the thought of Boyle and Clarke, it isdifficult to believe that Leibniz was systematically confused about the statusof the laws of nature. This is not just a matter of conventional piety towardsa great philosopher. Apart from the fact that Suarez, with whose thoughtLeibniz was acquainted, had already drawn the distinction, there are reasonsinternal to Leibniz’s system for resisting such a view. As we have seen, thereis evidence that Leibniz thought of himself as forging a middle path betweenthe necessitarian conception of the laws of nature that he associatedwith Spinoza and the strictly voluntarist conception that he attributed toDescartes; the laws of nature are contingently true, but morally necessary inthe sense that God’s choice of them is determined by his subscription tothe Principle of the Best. Clearly, such a position makes sense only on theassumption that laws of nature are universal propositions with a truth-value;if the laws of nature were simply imperatival in form, the question of theirstatus as necessary or contingent would not arise. Perhaps, in the case ofLeibniz, it is safe to say that he was generally clear about the distinctionbetween the prescriptive and the descriptive senses of the term ‘law’, even iffor polemical purposes he was sometimes tempted to blur the distinction.Indeed, trading on the prescriptive sense may on occasion have served thepurposes of an ad hominem argument, for as Vailati remarks, Clarkeexploited the prescriptive conception of the laws of nature in order toargue for a version of occasionalism.25

23 Quoted in Valiati, Leibniz and Clarke, pp. 141, 142.24 Valiati, Leibniz and Clarke, p. 142; cf. C. Wilson, ‘De Ipsa Natura’, p. 162.25 Vailati, Leibniz and Clarke. pp. 141–2.



I I I

Some of Leibniz’s arguments for the thesis that occasionalism involves perpet-ual miracles seem surprisingly flawed. And Leibniz may not seem to strengthenhis case philosophically when, for polemical purposes, he helps himself to thenotion of occult qualities. Commenting on the supposition that God couldorder the moon to move in a circle without there being a mechanical explan-ation thereof, Leibniz concludes: ‘To deny that it would be amiracle is to returnto absolutely inexplicable occult qualities which are decried today with somuchreason’ (G IV 595). Initially, what is perhaps most striking here is the irony ofLeibniz’s invocation of occult qualities in a critique of occasionalism. For, as wehave seen, it is plausible to suppose that the deep philosophical motivation foroccasionalism is the desire to eliminate natural causality as the last occultquality; the successor concept to the concept of natural causality is the conceptof law, and this concept is clear and distinct because laws can be expressed inmathematical terms. Yet here Leibniz objects that it is precisely the occasional-ists who are guilty of reintroducing occult qualities by their elimination ofnatural causality. Such a move on Leibniz’s part may be rhetorically effective,but we may suspect that it is lacking in philosophical substance.

In fact, such a judgement would be premature: Leibniz’s invocation ofoccult qualities in his critique of occasionalism proves to be surprisinglyilluminating. Today when we think of occult qualities we are likely to call tomind the vis dormitiva explanations of the Scholastics, and such dispositionalproperties serve to clarify Leibniz’s case, at least, by way of analogy. Consider aphilosopher who subscribes to the following commitments. First, ultimatescientific explanations can be given in terms of dispositional properties; theyare not merely placeholders for deeper explanations in terms of categoricalmicrostructural properties. Thus, when we say that the glass broke because ofits fragility, no further explanation is called for or even possible. Secondly, as amatter of ontology, these dispositional properties are not grounded in any-thing more basic, such as the chemical structure of the glass. Such a combin-ation of commitments is likely to strike many of us as ‘Scholastic’ in apejorative sense. If we now substitute laws for dispositions, and causal powersfor non-dispositional grounds, we are in a position to understand Leibniz’shostility to occasionalism. For Leibniz sees the occasionalists as analogouslyholding that ultimate explanations can be given in terms of laws, and thatthese laws do not need to be grounded in natures or causal powers. And to aneo-Aristotelian like Leibniz, such a set of commitments seems as objection-able as the Scholastic position on dispositional properties is likely to do to us.Of course the case of dispositional properties serves as an analogy only; it isnot literally an illustration of Leibniz’s point. Leibniz objects that laws need tobe grounded in causal powers, and thus what plays the role of grounding, for



Leibniz, is at least quasi-dispositional in character.26 But the modern critiqueof Scholastic appeals to dormitive powers and Leibniz’s critique of occasional-ism have one important thing in common: they both turn on the point thatthere is something seriously missing in the position under attack; they both failto satisfy the grounding requirement. And this is sufficient to enable us to seethe point of Leibniz’s seemingly merely-rhetorical claim that occasionalisminvolves the reintroduction of occult qualities.

IV

One issue that has received little attention is how Leibniz’s critique of occa-sionalism is affected by the development of his system in the direction of thetheory of monads that is characteristic of his later years. Fortunately, Leibniz’scorrespondence with the Cartesian De Volder supplies much of the materialnecessary to answer such a question. In this exchange Leibniz is concerned toexpose not just the inadequacies of the Cartesian conception of matter forphysics, but also to explain the relationship between his science of dynamicsand his theory of monads; indeed, Leibniz insists that the physical theory offorces is the gateway through which to pass to the true metaphysics (G II 195;L 593). And though occasionalism is not the principal target of attack in thisexchange, it is not forgotten either; in a number of places Leibniz insists thathis theory of monads is the true alternative to occasionalism.Occasionalism may not be the chief issue in the exchange with De Volder,

but there is no doubt about the implications of Leibniz’s position for thatsystem; in explaining his theory of monads to De Volder Leibniz shows that heis in a sense moving even further away from occasionalist tenets. Leibnizcontinues to maintain his principle that laws must be grounded in the naturesof things, but his position is complicated by the fact that he now recognizestwo levels of grounding corresponding to two levels of forces. Against theCartesians, including the occasionalists, Leibniz insists that the laws of motionforce us to recognize the existence of dynamic properties in bodies by virtue ofwhich these laws obtain:

26 Donald Rutherford has pointed out to me that, for Leibniz, a causal force is not simply apower that would act if certain conditions were realized, but a power that does act unless it isprevented. See, for example, ‘On the Correction of Metaphysics and the Concept of Substance’(G IV 469; L 433): ‘Active force . . . contains a certain act or (sive) entelechy and is thus midwaybetween the faculty of acting (facultatem agendi) and the act itself and involves a conatus. It isthus carried into action (operationem) by itself and needs no help but only the removal of animpediment.’ Leibniz’s account here makes it appropriate to describe causal powers or forces onhis view as quasi-dispositional.



You very rightly observe, in agreement with my own opinion, that it is inopposition to the laws of power, cause, and effect, for a great body to be movedby a smaller one without penalty. But from this fact I prove that the body containssomething dynamic by virtue of which the laws of power are observed. Ittherefore contains something besides extension and antitypy, for no such thingcan be proved from these two alone.

(G II 184; L 520)

Such claims are of course all that Leibniz needs in order to distance himselffrom the occasionalists, but in fact he goes further; for he now insists that the‘forces which arise from mass and velocity are derivative, and belong tophenomena’ (G II 251; L 530); what these physical forces derive from is theprimitive forces of monads or simple substances. Leibniz is at some pains toemphasize the explanatory autonomy of his science of dynamics; the physicistdoes not need to concern himself with the properties of monads:

But in phenomena, or [seu] in the resultant aggregate, everything is explainedmechanically, and so masses are understood to impel each other. In thesephenomena it is necessary to consider only derivative forces.

(G II 250; L 529)

But, as Leibniz goes on to explain, though the physicist need not concernhimself with such issues, the metaphysical truth of the matter is that theseforces stand in need of ontological foundations. When De Volder ventured tosuggest that there might be only such derivative forces, he received a dustyanswer from Leibniz (G II 251; L 530). Thus from the standpoint of his latermetaphysics, the occasionalists are at two removes from the truth, as it were.Not merely do they fail to see that laws must be grounded in physical forces,but they fail to see that these forces must in turn be grounded in the reality ofmonads.

Although there is no doubt that this is Leibniz’s official later position, it isworth asking whether monadology does not have the resources for a moreaccommodating reply to occasionalism. Let us begin by considering onefamous Leibnizian objection to occasionalism that we have so far ignored:the occasionalist conception of substance as being wholly devoid of genuinecausal powers leads to Spinozism:

This again shows that the doctrine of occasional causes which some defend canlead to dangerous consequences . . . though the consequences are no doubt notintended by its very learned defenders. Far from increasing the glory of God byremoving the idol of nature, this doctrine seems, with Spinoza, to make God intothe very nature itself of things, and to reduce created things into mere modifica-tions of a single divine substance. For that which does not act, which has no activeforce, which is robbed of any distinguishing characteristic, and finally of allreason and ground of permanence, can in no way be a substance.

(G IV 515; WF 221)



Thus Leibniz consistently subscribes to the principle that if x is not the bearerof genuine causal powers or forces, x is not a substance. Suppose, now, thatLeibniz were also committed to the converse conditional: if x is not a sub-stance, then x is not the bearer of genuine causal powers or forces. Let us callthis the ‘Principle of Substantial Causality’ (PSC). But in Leibniz’s laterphilosophy the only true substances are monads or simple substances; asLeibniz tells De Volder, ‘only simple things are true things; the rest are beingsby aggregation, and therefore phenomena’ (G II 252; L 531). Now monadsoccupy the ground floor of Leibniz’s metaphysics, and are thus below thelevel of phenomena with which physics is concerned. Thus, if monads aloneare the true bearers of forces, then any appeal to such forces would bebanished from the province of scientific explanation; such explanationswould appeal rather to ‘abstractions’, as Leibniz terms them, such as thelaws of physics (G II 252; L 531). As metaphysicians we would indeed needto recognize that the realm of phenomena—the subject matter of physics—isgrounded in the properties of monads, but as philosophers of science wecould blithely ignore this fact; we would insist on the autonomy of scientificexplanations with respect to these metaphysical foundations. Thus, if Leibnizsubscribed to PSC, he could still uphold his metaphysical objection tooccasionalism, but as a philosopher of science he could accommodate theoccasionalist insistence on the irrelevance of genuine causal powers or forcesto the enterprise of science.27

The evidence of the exchange with De Volder strongly suggests that Leibnizdoes not subscribe to PSC; as we have seen, he tells his correspondent that thederivative forces belong to phenomena that are not substances but are merelyaggregates of substances (G II 251; L 530). But though this is Leibniz’s officialposition, there are some passages—even ones bearing directly on occasional-ism—that seem more sympathetic to PSC. In places Leibniz seems to short-circuit the discussion of physical, derivative forces, and move directly to aconsideration of forces at the ground-floor metaphysical level. Consider thefollowing passage:

Last of all, you add: ‘Particulars act on each other and are subject to change withrespect to actions. How this can be explained by substances which do not act oneach other is obscure to me.’ This seems to be aimed at my opinion about the pre-established harmony between simple substances, which cannot act upon eachother. Yet they do produce a change in themselves, and it is necessary for this tohappen from your own point of view as well. For you acknowledged above thatthere is an internal basis for forces or actions, and so we must recognize aninternal principle of change. And unless we do there will be no natural principleof change and therefore no natural change. For if the principle of change were

27 In this spirit Leibniz need not take a stand on the issue of whether terms that appear to referto physical forces refer to nothing at all or simply nothing that is fully real.



external to all and internal to none, there would be none at all, and we would haveto turn back with the occasionalists to God as the only agent. It is therefore trulyinternal to all simple substances, since there is no reason why it should be in onerather than another, and it consists in the progress of the perceptions of eachmonad, the entire nature of things containing nothing besides.

(G II 271; L 538)

Here Leibniz argues directly for forces in monads on the basis that they satisfythe demand for a principle of change that is internal to things; there is nosuggestion that this demand might be equally satisfied by recognizing aprinciple of change in bodies, that is, at the phenomenal level. Perhaps itmay be said that in this passage Leibniz is responding directly to an objectionto his theory of pre-established harmony, and that he does not mean toexclude the recognition of ‘principles of change’ at the level of bodies orphenomena. But at least this passage suggests that the theory of monadscontains the resources for confining causal powers or forces to the ground-floor metaphysical level; certainly there is nothing in such a restriction thatwould weaken the response to the metaphysical challenge of occasionalism.And if Leibniz were to respond in this vein, he could nonetheless accommo-date the occasionalist insight that science is an investigation into laws, notcauses. But officially, at least, Leibniz is not prepared to take this line.

Leibniz’s debate with occasionalism has traditionally been seen as a ratherquaint and outdated controversy over God’s relationship with the createdworld. It is true of course that the debate is often couched in theologicalterms. Leibniz famously complains that the occasionalists appeal to perpetualmiracles and invoke God as a deus ex machina. But despite the theologicallanguage, the issues that divide Leibniz and Malebranche are anything butquaint or outdated; in fact, they are surprisinglymodern ones. For what is reallyin question is the nature of the scientific enterprise and its metaphysicalfoundations. In this debate, as we have seen, a partisan of a law-based concep-tion of science is confronted by a partisan of a cause-based conception. There isof course a sense in which by defending the latter position Leibniz is the moreconservative of the two thinkers, but to say this is certainly not to say that hisposition has been superseded. On the contrary, whether science is fundamen-tally about laws or about causes remains very much a live issue today.



10

Causality and Creation in Leibniz

Leibniz is famously committed to the following three metaphysical claimsconcerning causality:

(1) No created substances causally interact with one another.(2) God causally acts on created substances.(3) Every created substance is the causal source of all its states.

Obviously these three claims do not constitute an inconsistent triad, but theyare philosophically troubling nevertheless. With regard to (1) and (2), it isnatural to wonder how Leibniz is entitled to make an exception to his denial oftranseunt causality. This problem is particularly acute for Leibniz, since unlikeDescartes he is not in a position to take refuge in God’s omnipotence; hecannot say that though no two substances can causally interact, God is able todo what is metaphysically impossible. With regard to (1) and (3), the problemis less obvious, for at first sight they seem to complement each other; but it islegitimate to ask, as Louis Loeb has done, whether Leibniz can offer argumentsfor (1) which do not also tend to show the falsity of (3).1 At least Leibniz owesus an explanation of why immanent causality can be defended, while transeuntcausality between created substances must be ruled out. And it is not clear howLeibniz addresses this issue.Since the beginning of this century commentators have tended to try to solve

these problems by appealing to the so-called logicist thesis. Russell and Cou-turat famously argued that Leibniz derived his metaphysics from his logic; thatis to say, Leibniz’s real grounds for his striking metaphysical theses concerningcausal relations are to be found in his concept-containment theory of truth. Inrecent years, however, a number of writers have pointed out serious difficultiesin the logicist thesis; they have not only detected gaps in the supposed deriv-ation, but they have questioned whether Leibniz even intended to offer such aderivation of his metaphysics from his logic. Moreover, even if the logicist

1 L.E. Loeb, From Descartes to Hume: Continental Metaphysics and the Development ofModern Philosophy (Ithaca, NY and London: Cornell University Press, 1981), pp. 271–2. I amgrateful to Pauline Phemister and an anonymous referee for helpful comments.


thesis were successful in showing how Leibniz could endorse (1) and (3), itwould throw no light on his advocacy of (2); indeed, the logicist thesis wouldtend to imply that (2) is false. By virtue of the concept-containment theory oftruth, God must have a complete concept which contains everything which istrue of him; thus if one can validly argue from the fact that a substancepossesses a complete concept to the denial of transeunt causality, it wouldfollow that God does not act causally on any created substance.

In this essay I shall try to solve the puzzles posed by the triad of metaphys-ical claims without availing myself of the logicist thesis. In sections I and II,I shall argue that, despite appearances, the kind of causality which Leibnizdenies in the case of created substances is not the kind of causality which heaffirms in the case of God’s action on creatures; thus Leibniz is not simplymaking an ad hoc exception for God. In later sections I shall argue that God’saction on creatures provides a model for the intrasubstantial causality whichLeibniz affirms. Thus the solution to the puzzles posed by (1) and (2) alsoholds the key to solving the puzzles posed by (1) and (3). The central idea isthat there is a positive model of causality which underlies Leibniz’s commit-ment to all three propositions; God conforms to this model, and so do createdsubstances in their immanent actions; but created substances in their relationswith each other do not. I do not claim that this model fits all the texts, or thatLeibniz was completely satisfied with it; indeed there may be problemsconcerning divine concurrence which it leaves unsolved. But I hope to identifyan important strand in the tissue of Leibniz’s teachings concerning causality.

I

We can perhaps best approach the problems which Leibniz faces in justifyinghis commitment to (1) and (2) by comparing his position with Malebranche’soccasionalism. Leibniz himself invites this comparison, for he tells a corres-pondent, L’Hospital, that he agrees with Malebranche in holding that Godalone acts causally on created substances:

I am very much of the opinion of Father Malebranche inasmuch as he believesthat only God acts immediately on substances by a real influence.

(12/22 July 1695, MLR 318)

In a letter to Remond, Leibniz narrows the focus to human minds, butotherwise he makes the same point:

One must consider that not only in the system of Father Malebranche but also inmine, God alone is the immediate external object of souls, exercising on them areal influence.

(4 November 1715, G III 660)



Leibniz is silent here about the fact that unlikeMalebranche he accepts genuineimmanent causality, but he is correct in identifying the area of agreement.Although he himself invites it, the comparison with Malebranche is not

flattering to Leibniz, for unlike Leibniz, Malebranche has a clear and rathercompelling case for saying that God alone is a true intersubstantial cause.Malebranche’s main argument for this thesis famously proceeds from ananalysis of causality in terms of necessary connection; as he puts it in TheSearch After Truth ‘a true cause as I understand it is one such that the mindperceives a necessary connection between it and its effect’ (SAT 6.2.3, OCM II316; LO 450). On the basis of this definition Malebranche draws the conclu-sion that God is a true cause by virtue of his omnipotence: it is a contradictionto suppose that an omnipotent being should will a state of affairs and that stateof affairs not obtain. By contrast, no creature is a genuine cause since there isno necessary connection between the states of creatures. It is this secondnegative argument which has led commentators to see a remarkable kinshipbetween Malebranche and Hume.If Malebranche’s analysis of the causal relation seems to look forward to

Hume, Leibniz’s analysis appears to look backwards in time; for at the heart ofhis discussion is the concept, not of necessary connection, but of influx—aconcept which Leibniz attributes to the Scholastics. It is in terms of thisanalysis that Leibniz seeks not merely to argue for the denial of causalinteraction between created substances but also, on the face of it, to defendthe positive thesis of God’s causal action on creatures. Some writers havesuggested that the Leibnizian analysis of causal interaction in terms of influxhas more in common with the Malebranchian analysis than might appear;both result from imposing the requirement that causality be ‘intelligible’.2 Weshall see that at least one text is difficult to reconcile with this claim, but that isnot the issue here. The important point is that it is much less clear in Leibniz’scase than in that of Malebranche how his analysis of causality entitles him toassert (1) and (2). Indeed, Leibniz’s discussion of the concept of influx raisestwo main problems which do not arise in the case of Malebranche.In the first place, it is not clear whether Leibniz thinks that causal inter-

action between substances is correctly analysed in terms of influx. Conven-tional wisdom suggests that he believes it is. Thus Edward Craig, for instance,writes that for Leibniz causal interaction between two substances would callfor the transfer of an element from one to the other—a metaphysical influx,3

and according to Craig this analysis is ultimately grounded in the intelligibilityrequirement. (Certainly, on this view it is perfectly clear how Leibniz can movefrom the denial of influx to the denial of causal interaction.) As against this,

2 For example, E. Craig, The Mind of God and the Works of Man (Oxford: Clarendon Press,1987), p. 55.

3 Craig, The Mind of God and the Works of Man, p. 55.


Causality and Creation in Leibniz 153

however, we must set some early remarks on Suarez, the Scholastic with whomLeibniz particularly associates the concept of influx. Leibniz complains thatSuarez shares the general Scholastic tendency to invent barbarous neologisms:

The Scholastics before him had been exerting themselves to find a generalconcept of cause, but fitting words had not occurred to them. Suarez was notcleverer than they, but bolder, and introducing ingeniously the word influx, hedefined cause as what flows being into something else, a most barbarous andobscure expression. Even the construction is inept since influere is transformedfrom an intransitive into a transitive verb, and this influx is metaphorical andmore obscure than what it defines. I should think it an easier task to define theterm ‘cause’ than this term influx used in such an unnatural sense.

(Preface to an Edition of Nizolius, G IV 520; L 126)

Thus Suarez shows himself here to be an incompetent philosopher andgrammarian. But if Suarez’s definition of ‘cause’ is such a bad one, onewonders how Leibniz can move from the denial of influx to the denial ofcausal interaction between substances, for the validity of this move requiresthat influx be at least a logically necessary condition of such interaction. Ofcourse Suarez aims to state an equivalence between cause and influx, butLeibniz’s point is surely not that Suarez confuses a condition that is merelynecessary with one that is both necessary and sufficient.

Perhaps the solution to this puzzle lies in seeing that there is a hesitation inLeibniz’s thought between reductionist and eliminativist approaches to theissue of causal interaction. The tone of Leibniz’s early comments on Suarez inthe Preface to Nizolius is reductionist in spirit: Leibniz does not accept theexistence of influx because he does not know what the term means, but heshows no sign of wanting to deny the existence of intersubstantial causality.Leibniz seems indeed to be leaving the door open to a reductionist account ofcausal interaction. Such an analysis is suggested in the paper Primary Truths:‘What we call “causes” are in metaphysical rigour, merely concomitant requis-ites’ (C 521; P 90).4 Or again, Leibniz offers another analysis in terms of hisdoctrine of expression. How the analysis is supposed to go need not concernus here. The important point is that Leibniz sometimes suggests that ourordinary statements about causal interaction can be understood in such away that they come out true.

More typically, however, Leibniz adopts the eliminativist approach to theissue of causal interaction. Certainly this is the side of Leibniz that is betterknown. When Leibniz simply denies the existence of causal interaction be-tween created substances, he tends to accept the influx analysis; he does not

4 Cf. H. Ishiguro, ‘Pre-established Harmony versus Constant Conjunction: A Reconsiderationof the Distinction Between Rationalism and Empiricism’, in A. Kenny (ed.), Rationalism,Empiricism, and Idealism, p. 68.



look around for a better analysis that would preserve the truth of our ordinarycausal statements. Thus in the correspondence with Arnauld, Leibniz writes: ‘Imaintain that one created substance does not act upon another, in metaphys-ical rigour, that is to say with a real influence’ (January 1688, G II 133; LA 167).It should be noted, however, that despite their assignment of different truth-values to such statements, the two approaches are alike in one respect: theyagree that there is no such thing as influx. In a structurally similar way,eliminative and reductive materialists agree that there is no such thing as theCartesian res cogitans but disagree over whether this licenses the denial of theexistence of minds.Leibniz’s dominant approach to the issue of causal interaction thus seems to

be eliminativist rather than reductionist in spirit. But this leaves open thefurther question of the strength of his denial of intersubstantial causality in thecase of creatures; in particular, it may be wondered whether such causality issupposed to be metaphysically or merely morally impossible (or somethingweaker still). Since Leibniz asserts on numerous occasions that God acts oncreatures by influx, it is natural to suppose that his negative thesis must be aweak one: the concept of influx is coherent, but no created substances fallunder it. In this way Leibniz could point to the parallel with Malebranche.Malebranche believes that the concept of necessary connection is a coherentone which is instantiated by the will of God; but he denies that any relationsbetween creatures fall under it.At other times, and more typically perhaps, Leibniz appears to envisage a

stronger version of the thesis that influx between creatures is unintelligible. Thestrongest version of all is suggested by the early comments on Suarez in thePreface to Nizolius: influx is unintelligible because the very term is a nonsenseone. (As we have seen, however, Leibniz seems to leave open here the possibilitythat a different analysis of our ordinary causal statements might preserve theirtruth.) But more famously, he seems to hold that the assertion of influx isunintelligible not because it is literally nonsensical but because, while in somesense meaningful, it involves a metaphysical impossibility. In the Monadology(para. 7) Leibniz famously attacks the theory of influx for involving themetaphysical fiction of accidents becoming detached from their substances:

Monads have no windows by which anything could come in or go out. Accidentscannot become detached or wander about outside substances as the ‘sensiblespecies’ of the Scholastics used to do.

(G VI 607–8; P 179)

In order to bolster his case for metaphysical impossibility Leibniz may behelping himself to the assumption that influx involves accidents existing for atime, however brief, without being the accidents of any substance. And forLeibniz, anyone who asserts that assumption fails to understand the necessarytruth that accidents are essentially accidents of some substance. But the



defender of influx need not make this questionable assumption. All that he hasto concede is that numerically the same accident can exist at different times indifferent substances, and this does not imply that accidents can exist outsideany substance whatever. But whether or not Leibniz is unfair to his opponentshere, it seems clear that influx between created substances is supposed to bemetaphysically impossible. But if influx, understood in terms of the transfer ofaccidents, is impossible between created substances, one may wonder why it isnot also impossible in the case of God’s action on creatures.5

It may be replied that what rules out influx in the case of created substancesis the transfer of accidents, and that since God has no accidents, this objectionhas no purchase. But such a reply is unsatisfactory. In the first place, the claimthat God has no accidents should not be simply taken on trust. In one sense ofthe term ‘accident’ the claim is of course true: if accidents are opposed toessential properties, then God has no accidental properties in this sense. But‘accidents’ may also be taken to mean individual accidents, and in this sensethey are opposed not to essential properties but to property-universals whichmay be multiply instantiated. When accidents are understood in the sense ofindividual accidents, it is by no means clear that God does not have them.Indeed, Leibniz would surely wish to maintain that there is a goodness-instance in God which is numerically different from the goodness-instancein Francis of Assisi.

But in the second place, and more importantly, as a defence of Leibniz thereply seems misconceived; for it proves too much. If influx, according toLeibniz, essentially requires the transfer of accidents, and God has no acci-dents, then the correct conclusion is that there is, and can be, no influx in thecase of God. At most the reply succeeds in showing that Leibniz has differentgrounds for excluding action by influx in God’s case and in the case of createdsubstances.

Although this defence of Leibniz is on the face of it misconceived, it hints atthe correct approach to the problem. For the proper moral to be drawn is thatwhen he ascribes action by influx to God, he cannot be thinking in terms of thetransfer of accidents model; whether or not God is supposed to have accidents,there are insuperable objections to this model. Thus when Leibniz assertsaction by influx in God’s case and denies it in the case of creatures, the term‘influx’ cannot be used univocally. When Leibniz denies influx betweencreated substances, he is denying that one substance can cause a change ofstate in another created substance which is already in existence, and as we haveseen, he denies this because it involves the metaphysical fiction of an exchangeof accidents. But as study of the texts confirms, God’s influx on createdsubstances is not at all like this: God does not bring about a change of state

5 See E. O’Neill, ‘Influxus Physicus’, in Nadler (ed.), Causation in Early Modern Philosophy,pp. 27–55.



in a created substance which exists independently of his causal action; rather,God acts on finite substances by creating them and conserving them inexistence, where conservation is to be understood in terms of continuouscreation. In the letter to L’Hospital quoted earlier, Leibniz follows up hisclaim that God acts on us by a real influence by explicating it in terms of‘the dependence we are in with respect to God who brings it about that we areconserved by a continuous creation’ (MLR 318). Again, a few years later,he offers the same explanation: ‘I agree that God acts at all moments oncreatures by conserving them’ (Commentary on Lamy, De la Connoissancede Soi-Même, 30 November 1702, MLR 372). Thus Leibniz is not simplymaking an ad hoc exception to a general principle excluding intersubstantialcausality. Rather, he is asserting in the case of God something quite differentfrom what he denies in the case of creatures.

II

The proposed solution of this problem suggests an approach to solving theproblem presented by Leibniz’s subscription to (1) and (3). Leibniz’s commit-ment to immanent causality is not in doubt; he states the thesis very clearlyand explicitly in the course of criticizing the doctrine of occasional causes:

The system of occasional causes must be partly accepted and partly rejected.Every substance is the true and real cause of its immanent actions and has theforce of acting, and though they are sustained by the divine concurrence, itcannot however happen that every substance behaves only passively, and this isas true in the case of corporeal as in the case of incorporeal substances.

(Specimen Inventorum, note, 1696? MLR 315)

Yet one may wonder, as Loeb does, whether some of Leibniz’s argumentsagainst real intersubstantial causality do not also rule out real immanentcausality. In this section and the next I shall discuss a strand in Leibniz’sphilosophy which would allow him to defeat the objection which Loeb raises:the idea is that, for Leibniz, the immanent causality of created substance ismodelled on the creative causality of God. It is clear, then, that immanentcausality does not involve a troublesome transference of accidents; it thus doesnot succumb to the arguments which show that intersubstantial causality is ametaphysical impossibility.Consider, by way of preliminary stage-setting, one of the major themes of

Leibniz’s philosophy. On many occasions Leibniz seeks to do justice to theteaching of Genesis that man (i.e. the human mind) is made in the image ofGod. In the Discourse on Metaphysics (para. 36) Leibniz writes that ‘mindsalone are made in [God’s] image, and are, as it were, of his family, or like the



children of his house’ (G IV 461; P 46); nearly twenty years later, in thePrinciples of Nature and of Grace (para. 14), he repeats the same fundamentalidea: ‘the mind is not only a mirror of the universe of created things, but also animage of the Deity’ (G VI 604; P 202).6 The ‘image of God’ theme leads us toexpect that minds will resemble God not just by virtue of being true causes butalso in respect of the kind of causality they exercise; the immanent causality ofminds will be as much like divine creation as the nature of a created substancepermits. This expectation appears to be satisfied. In the Principles of Nature andof Grace (para. 14), for instance, Leibniz is explicit that, in at least some of itscausal activities, the human mind imitates divine creation:

The mind not only has a perception of the works of God, but is even capable ofproducing something like them, though on a small scale. For not to mention thewonders of dreams, in which we invent without effort (but also without will) thingswe could only discover after much thinking when awake, our soul is architectonicin its voluntary activities also, and, discovering the sciences in accordance withwhich God had regulated things . . . it imitates in its own sphere, and in the littleworld in which it is allowed to act, what God performs in the great world.

(G VI 604–5; P 202)

Leibniz stops short here of suggesting that the immanent causality of the mindresemblesGod’s creation in all its operations; he concentrates rather on a fewkindsof mental phenomena, such as dreaming and scientific discovery. In the earlierDiscourse on Metaphysics (para. 14), however, he pushes the analogy further:

In the first place it is very clear that created substances depend on God, whoconserves them and even produces them continually by a kind of emanation aswe produce our thoughts.

(G IV 439; P 26)

Leibniz invites us to conceive of God’s continuous creation in terms of thesupposedly more familiar model of our own causal activity in producing ourthoughts. But ontologically speaking, this puts the cart before the horse. It isthe mind’s production of its thoughts which is cast in the image of the divinecreation.

The hypothesis that God’s creation supplies a model for immanent causalitysuggests a solution to one puzzle. We have seen that Leibniz denies intersub-stantial causality between created substances while upholding divine action oncreatures, and at first sight it seems that this combination of theses sitsuneasily with the ‘image of God’ doctrine; if God acts causally on createdsubstances, then the ‘image of God’ doctrine would lead us to expect thatminds are also capable of such interaction. But on the proposed hypothesis theproblem can be solved. For God’s influx on creatures is not to be understood

6 This theme is stressed by Craig in The Mind of God and the Works of Man.



in terms of the transfer of accidents which Leibniz denies in the case of createdsubstances; it is to be understood rather in terms of continuous creation, andthere is an analogue of such creation in the case of minds.There is thus textual warrant for saying that Leibniz wants to model the

immanent causality of minds on divine creation; in this way Loeb’s objectionscould be overcome. It may be wondered, however, whether Leibniz wishes toextend this thesis to the whole realm of monads; in the Discourse on Meta-physics, for instance, he says that only minds are made in the image of God. Itis true that Leibniz seeks to reserve a special place in his ontology for minds orspirits; they have a privileged position by virtue of their capacity for reasonand self-conscious reflection, and it is by virtue of possessing these capacitiesthat they are made in God’s image. But there is a no less important strand ofLeibniz’s thought which is in tension with this first one. It is a major theme ofhis metaphysics that the fundamental building-blocks of the universe are ofthe same basic type, and that differences among monads are differences ofdegree only. The Law of Continuity in particular is hard to reconcile with theexistence of sharp divisions among monads. It is when this theme is upper-most that Leibniz seeks to extend the creation model across the board; in theMonadology (para. 48), for instance, he suggests that God’s will and power‘which is the source of everything’ correspond, though with greater perfection,to the immanent causality of monads in general.7

I II

The thesis that divine creation supplies a model for the immanent causality offinite substances is open to an obvious line of criticism. It is natural to objectthat Leibniz cannot possibly have believed in this model since there are radicaldifferences between the two kinds of causality of which he must have been wellaware. But here we need to be clear about what would constitute a successfulreply to such a criticism. It is not, I think, necessary to show that there is anexact fit between the immanent causality of created substances and the causal-ity of God; for the fact that finite created substances are both created and finiterules this out.What needs to be shown rather is that there are striking analogiesbetween the two cases; in other words, the standards of success are set by thetraditional medieval doctrine of analogical predication. In what follows I shallargue for the existence of such analogies in the course of responding to threeapparently powerful objections which urge the utter dissimilarity of the twokinds of causation; thus, a look at the strongest objections will serve to confirm

7 G VI 615; P 186. On the tension between the two themes in Leibniz, see D. Rutherford,‘Metaphysics: The Late Period’, in Jolley (ed.), The Cambridge Companion to Leibniz, p. 143.



the power of the model.8 The upshot of this discussion is that we can call bothGod and created substances ‘creators’ provided we are clear that what isinvolved is analogical predication. And this is all that is required in order todefend the thesis that the immanent causality of created substances is modelledon the creative causality of God.

1. The ex nihilo objection

Perhaps the most obvious apparent disanalogy is that God creates ex nihilo;intrasubstantial causality by contrast, consists, not in bringing something intobeing out of nothing, but rather in conferring a new form or modification onsome pre-existing mental material.

In one sense this objection must be correct; theological orthodoxy certainlyrequires Leibniz to acknowledge that God creates the universe out of nothing.But there is an important way inwhich an analysis of divine creation can point toa strong analogy with intrasubstantial causality. Although the universe is createdex nihilo, considered sub ratione possibilitatis it already has a potential existencein the divine intellect. How we understand the status of possible worlds in God’sintellect is of course an important and controversial issue. Some readers may betempted to say that such worlds already enjoy a kind of existence; thus con-sidered sub ratione possibilitatis our world exists as an object of God’s mind;alternatively, they may say that it exists ideally or that it subsists, where subsist-ence is supposed to be something less full-blooded than actual existence. Such aninterpretative strategy at least has the advantage of making divine creationappear less amazing; on this account, then, it may seem more like a potentialcousin of intrasubstantial causality. Far from conjuring this world into being outof nothing, God simply translates one kind of existence into another: idealexistence is converted into actual existence. But it is unclear that we really havea grip on the notion of ideal existence or subsistence, and there is room fordoubting whether Leibniz believed that existence comes in different varieties.

The true key to the analogy between divine creation and intrasubstantialcausality is furnished by Benson Mates’ analysis. According to Mates, when

8 One possible objection is that Leibniz’s God not only creates the universe but also conservesit, and that this constitutes a disanalogy with the causality of finite substances. The issue iscomplicated by the obscurity of Leibniz’s doctrine of divine conservation: at times he seems tosuggest that it involves the re-creation of finite things in existence from moment to moment, butat others he denies this. On this issue see G.H.R. Parkinson, Logic and Reality in Leibniz’sMetaphysics (Oxford: Clarendon Press, 1965), pp. 99–101. Perhaps, however, Leibniz’s doctrineof ‘marks and traces’ may be invoked to weaken the force of the disanalogy: the immanentcausality of created substances involves the activation of a pre-existing ‘mark’ which is conse-quently conserved in the form of a persistent ‘trace’. See Discourse on Metaphysics, para. 8 (G IV433; P 19).



Leibniz speaks of possible worlds in the mind of God he should not be taken tobe committed to a Platonistic ontology of abstract entities. On the contrary,talk of possible worlds in the mind of God should be understood rather aswhat Leibniz calls a compendium loquendi; that is, it is an abbreviated way ofspeaking about God’s capacities or dispositions.9 In Mates’s illustrativeexample, we may find it useful to speak of a number of tables which acabinet-maker could make, but such language should not be taken at facevalue; what we are really talking about is a set of capacities or dispositions onthe part of the cabinet-maker. In the same sort of way talk about possibleworlds in God should be understood as a shorthand expression for God’scapacities or dispositions to create worlds answering a certain description.On this analysis, then, creation is the activation of a divine disposition, and

it thus becomes possible to see a real analogy between divine creation andintrasubstantial causality. As is well known, Leibniz insists that there is moreto created souls than occurrent states; every soul comes into the worldendowed with a stock of mental dispositions, and its occurrent states areactivations of such dispositions. The most famous statement of this theoryoccurs in the New Essays, but for our purposes it is more appropriate to appealto theDiscourse on Metaphysics. It is in theDiscourse (para. 29) rather than theNew Essays that Leibniz is inclined to assert the fairly radical thesis that, forany occurrent thought, there is a corresponding mental disposition to havethat thought:

The soul must also be affected actually in a certain way when it thinks ofsomething, and there must be in it in advance not only the passive power ofbeing able to be affected in this way, which is already entirely determined, but alsoan active power, by virtue of which it has always had in its nature marks of thefuture production of this thought and dispositions to produce it at its time.

(G IV 454; P 38)

It is true that Leibniz is here concerned with ‘thoughts’, and strictly speakingthoughts are a subset of perceptual states. But it is natural to suppose that hewishes to generalize his thesis to all perceptual states of a mind; for anyoccurrent perceptual state, there is a corresponding disposition to have thatstate.The preceding analysis thus suggests an intriguing analogy between divine

causality and intrasubstantial causality; in both cases a dispositional propertyof a substance is activated. The analogy can, I think, be clearly strengthened intwo (possibly related) ways. In the first place, although Mates seems to use theterms ‘disposition’ and ‘capacity’ interchangeably, it is worth remarking thatLeibniz wishes to draw a distinction between them; to have a disposition to ç,

9 Cf. B. Mates, The Philosophy of Leibniz: Metaphysics and Language (New York and Oxford:Oxford University Press, 1986), p. 171.



for Leibniz, is a stronger concept than to have a mere capacity (faculté) to ç.10

To say of a soul, for instance, that it has a disposition towards a certainperceptual state is to say that it is differentially predisposed towards thatstate rather than some other state of which it is nonetheless capable. In thesame way we could say that although God is capable of creating other possibleworlds, he has a disposition to create the best possible world. In the secondplace, in each case no external stimulus is required to activate the disposition;finite substances, like God, enjoy total causal independence from all otherfinite substances. It is thus misleading to think of the dispositions in questionon the model of familiar physical examples such as fragility or solubility. Thesetwo points may be closely related, for it is possible that Leibniz thinks that thecorrect analysis of the claim that a substance has a disposition to ç is that thesubstance will ç unless it is prevented.

Although these analogies are impressive, there is one way in which theanalogy appears not to hold, and that concerns the content of the disposition;whereas intrasubstantial causality implies the activation of a disposition to thinkor perceive in a certain way, divine creation involves the activation of a divinedisposition to act in a certain way. It is worth enquiring here whether Mates’analysis does not offer the resources to strengthen the analogy further so thateven the difference in the content of the dispositions evaporates altogether.

Consider three claims that Mates attributes to Leibniz:

(1) Possible worlds are congeries (i.e. collections) of complete concepts.(2) Complete concepts are ideas in God.(3) Ideas in God are divine dispositions to think in certain ways.11

It follows from these three claims that possible worlds are congeries or collec-tions of divine dispositions to think in certain ways. Now since Leibniz holdsthat there is no information about a possible world which is not encoded in thecomplete concept of any individual substance within it, we can simplifymattersby removing the awkward talk of sets of divine dispositions: thus, withoutviolence to Leibniz’s thought, we can, I think, speak as if a possible world issimply one complete concept, and hence one divine disposition. Thus we cansay that the possible world containing Julius Caesar is the divine disposition tothink of Julius Caesar and of all those individual substances which are compos-sible with him. The actualization of the possible world containing Julius Caesar,then, is the activation of God’s disposition to think of Julius Caesar and all hisfellow compossible substances. But the activation of a disposition to think issimply an occurrent thought. It follows, then, that the actualization of thepossible world containing Julius Caesar is simply God’s occurrent thought of

10 See, e.g., Leibniz to Burnett, 3 December 1703, G III 291. Cf. Descartes, Comments on aCertain Broadsheet, AT VIIIB 357–8; CSM I 303–4.

11 Mates, Philosophy of Leibniz, pp. 174–8.



Julius Caesar and the compossible substances. Thus we arrive at the remarkableconclusion that creation is simply an occurrent thought of God’s, for toactualize a possible world is just to create it. In this way the analogy betweendivine creation and intrasubstantial causality receives a powerful and unex-pected boost; in divine creation, no less than intrasubstantial causality, amentaldisposition becomes an occurrent mental state.The conclusion that divine creation simply consists in a kind of divine

thinking is obviously heretical; as a Christian at least, Leibniz would not behappy with the view that you and I are simply thoughts in God’s mind. Somereaders may therefore be tempted to regard the conclusion as a reductio ofMates’ interpretative approach which crucially construes possible worlds interms of divine dispositions to think in certain ways.12 Nonetheless, though thedetails of Mates’ approach are controversial, it can hardly be denied thatLeibniz’s commitment to possible worlds ensures some analogy between divinecreation and intrasubstantial causality; in both cases the effect—whether theactual world or an occurrent perceptual state—has a kind of potential existencein the substance which produces it.

2. The transcendence objection

A second disanalogy between creation and intrasubstantial causality whichmight be alleged turns on the issue of divine transcendence. Although hecreates and continuously conserves the universe, God exists over and abovethe substances he creates; logically speaking, they have a life of their own, as itwere. Perceptual states, by contrast, are properties of the substances which aretheir causal sources; they thus depend on them logically. Indeed, Leibniz couldnot possibly hold that finite substances depend logically on God, for thatwould be, in effect, to deny their status as substances; it would be tantamountto the Spinozist heresy that finite things are modes of the one substance, God.In response to this objection at least two points can be made. In the first

place, although it is natural to try to unpack the transcendence of God in termsof claims about the logical independence of finite substances, it is not clear thatthis can be done; indeed, the issue here is more complex than it first appears.For whether there is a relation of logical dependence between two things issurely a function of how those things are described; we might express this bysaying that the concept of logical dependence is a linguistic rather than ametaphysical category. Thus, when finite substances are described as creaturesand God as a creator, then a relation of logical dependence holds; for ‘creature’and ‘creator’, like ‘cause’ and ‘effect’, are correlative terms. It is logically or

12 One problem with Mates’ approach is that it seems inconsistent with the doctrine that Godis pure act.



conceptually impossible that there should be a creature and no creator, just as,on some views at least, it is logically impossible that there should be anuninstantiated property. So there is an entirely natural description of finitesubstances and God under which their relationship comes out as one of logicaldependence. Any attempt to analyse the concept of transcendence in terms ofthe logical independence of substances must take account of this point.

But secondly, suppose we concede that Leibniz’s God is a transcendentbeing: in other words, there are genuine finite substances which are not merelymodes of God. Surprisingly perhaps, it does not follow from this concessionthat there is a radical disanalogy between divine creation and intrasubstantialcausality. For though perceptual states are indeed properties of finite sub-stances, they are certainly not properties of the antecedent states of thesubstances in which they inhere; on the contrary, this relation is one of causaldependence. The point is crucial, for on reflection it is clear that the analogybetween creation and intrasubstantial causality is supposed to hold betweenGod and creatures on the one hand and discrete perceptual states of finitesubstances on the other. Although Leibniz may say that it is substances whichproduce their states, this is only a loose way of speaking; in strictness, it isperceptual states which causally produce other perceptual states of the samesubstance.13 Thus the fact that God transcends his creatures in no way pointsto a disanalogy. God exists over and above his creatures, it is true; but it is noless true that later perceptual states exist over and above their causal antece-dents. There is thus a perfectly good sense in which we can say that laterperceptual states transcend the earlier perceptual states of those substances.

3. The appetition objection

The final alleged disanalogy turns on a positive property which substancespossess, at least according to Leibniz’s later philosophy; it is by appetition thatcreated substances cause their internal states. But divine creation is notremotely like the appetition of monads.

The claim that there is no analogy between divine creation and appetitionmay resonate with many readers, but what is supposed to be its basis? Twopossible defences of the claim come to mind. In the first place, it might beurged that appetition, unlike divine creation, occurs in time; it is the action ofthe principle in the monad by virtue of which it makes the temporal transitionfrom one perceptual state to its successor. But this argument rests on a

13 The view that perceptions are causally efficacious in this way has been challenged byM. Bobro and K. Clatterbaugh, ‘Unpacking the Monad: Leibniz’s Theory of Causality’, TheMonist 79 (1996), 408–25. However, I think that what they call the ‘efficacious perception view’ isconsistent with, rather than a rival to, what they call the ‘monadic agency view’ which theyattribute to Leibniz.



straightforward mistake. For it is one of the central teachings of Leibniz’s latermetaphysics that space and time are purely phenomenal; temporal predicates,like spatial predicates, have no application at the ground-floor level of hismetaphysics. Thus since appetition is a property of monads, it cannot be atemporal property. It is true that Leibniz, in company with many philosophers,develops his views more fully with respect to space than time, but officially he iscommitted to the thesis that they aremetaphysically on a par; whatever is true ofspace is supposed to be true, mutatis mutandis, of time as well.A second argument for a radical disanalogy would appeal to the fact that

appetition, unlike divine creation, involves some kind of striving or effort; asLeibniz tells Wagner on 3 March 1698, ‘in monads effort [nisus] and appetiteare the same’ (Gr I 395). And it might be urged that divine creation cannotinvolve any kind of striving, for this would imply the attempt to remedy a lackor deficiency. But there can be no lack or deficiency in God who is metaphysic-ally and morally perfect.Whether striving does imply imperfection in this way may be disputed;

echoing a debate between Spinoza and his imagined critics we can observe thatstriving may be directed towards communicating goods to an external beingrather than to remedying some internal lack or deficiency.14 But in one waythe striving of monads in appetition is not an embarrassment at all, for itdraws our attention to a clear point of analogy; appetition is essentiallydirected towards a goal. There can thus be no doubt whatever that appetitionresembles divine creation in having a teleological character. Leibniz is explicitthat in creating this universe God acts from final causes; creation is directed bythe purpose of maximizing perfection.The fact of the analogy cannot be disputed, but just how strong we take it to

be depends on our interpretation of appetition, and here there is room fordisagreement, for Leibniz is not as forthcoming on this topic as we could wish.But on the face of it there are two models of appetition which differ in theiraccounts of the goal involved. On one model, which is perhaps the morefamiliar, the goal of appetition is a certain perceptual state. The locus classicusfor this model is in the Monadology (para. 15):

The action of the internal principle which produces the change or passage from oneperception to another may be called appetition; it is true that the appetite cannotalways attain completely the whole of the perception towards which it tends, but italways attains something of it, and arrives at new perceptions.

(G VI 609; P 181)

But other texts suggest a different, more intriguing model according to whichthe goal of appetition is always the (apparent) good; on this model future

14 B. de Spinoza, Ethics, ed. and trans. G.H.R. Parkinson (Oxford: Oxford University Press),Part I, Appendix, p. 109.



perceptual states are not the goal or end of appetition, but rather the means bywhich the goal or end is achieved: a monad’s transition to a perceptual state isto be explained in terms of its (perhaps unconsciously) perceiving it to bethe necessary means to bring about what seems best to it. Appetition thusconforms to an entirely familiar pattern of teleological explanation in terms ofends and means. Taken together, two passages from the Monadology (para.79) and the Principles of Nature and of Grace (para. 3) suggest this model:

Souls act according to the laws of final causes, by appetition, ends and means.(G VI 620; P 192; emphasis added)

The perceptions in the monad spring from one another according to the laws ofthe appetites or the final causes of good and evil.

(G VI 599; P 196)

On this model then there is indeed a strong analogy with divine creation; Godsets himself the goal of maximizing perfection, and creation itself is the meansto achieve this goal. Moreover, there is a sense in which the goal of both Godand monads is the apparent good.15 The only point of disanalogy on thismodel is that, whereas in the case of God the apparent good is necessarily thereal good, in the case of monadic appetition they may fail to coincide; whetherthe apparent good in fact coincides with the real good is of course a function ofthe clarity and distinctness of a monad’s perceptual states.On any interpretation of appetition there is some analogy between divine

creation and appetition since Leibniz stresses the goal-oriented character ofthe latter. But it may seem that the analogy is rather weak on the morefamiliar, first model according to which perceptual states are the ends ratherthan the means. As we have seen, in terms of the analogy, new perceptualstates are what correspond to the universe which God creates, but God’s goalin creating this universe is the maximization of the good, not creation itself.Moreover, whereas on this model monads strive or tend to new perceptualstates, God does not strive towards creation. Thus the similarity may seem tobe confined to a vague common element of goal-directedness.

In a speculative spirit I wish to suggest that the analogy need not be as weakas this. The strategy is to invoke Leibniz’s notorious Daseinstreben doctrine:this is the thesis that possible worlds in God strive for existence in proportion totheir quantity of reality or essence. Recall that in an earlier section of thischapter we showed how talk of possible worlds could be interpreted in areductionist spirit in terms of divine dispositions to think in certain ways.Thus on this reductionist approach the striving of possible worlds for existenceis the striving of certain divine dispositions to be actualized; we may think hereperhaps of a similar struggle of character traits (dispositional properties) to find

15 For help with this point I am grateful to José Benardete.



expression in behaviour. On this view there would once again be a stronganalogy between appetition and divine creation; in God’s creation the bestpossible world, considered as a divine disposition, strives to become actual, justas in appetition potential perceptual states strive to become occurrent.The proper interpretation of the Daseinstreben doctrine is of course one of

the most controversial issues in Leibniz’s philosophy. Many commentatorswould dispute the thesis that the doctrine should be taken literally, as I havedone; they prefer to understand it as a metaphorical way of expressing thethesis that possible worlds have a claim on God’s choice in proportion to theirdegree of perfection.16 Moreover, not all scholars will agree that possibleworlds should be reduced to divine dispositions to think in certain ways.The present reconstruction is thus highly speculative. But this fact shouldnot be allowed to divert attention away from the core thesis which is solidlysupported by the texts: appetition is teleological in nature, and thus signifi-cantly analogous to divine creation.The thesis that for Leibniz intrasubstantial causality is modelled on divine

creation thus can be defended against the objections that there are radicaldisanalogies between the two kinds of causality. But though the creation modelrepresents an important strand in Leibniz’s metaphysics, it is not the only one;there are passages where Leibniz says things which are in some degree at oddswith it. In the Theodicy (para. 395), for example, in the course of opposingoccasionalist claims Leibniz denies that the production of modifications in-volves creation:

The production of modifications has never been called creation, and it is abusingterms to scare the world. God produces substances from nothing, and substancesproduce accidents by the changing of their limits.

(G VI 351; H 360)

The apparent conflict between this passage and the creation analogy might bemitigated in two ways. In the first place, Leibniz’s target here is the occasional-ist doctrine that the production of modifications is literally a case of divinecreation itself; he is not attacking the thesis that it involves quasi-creation onthe part of finite substances. Secondly, the examples which Leibniz offers allinvolve changes in physical modifications; by contrast, the creation modelapplies at the ground-floor level of Leibniz’s metaphysics at which the percep-tual states of monads are produced by appetition. But it must be admitted thatthe passage seems not to agree in spirit with the creation model of intrasub-stantial causality. Perhaps the important thing to be said here is that it occursin the course of a popular work, the Theodicy, which Leibniz saw fit to publishin his lifetime. It is very much to the point that the creation model is strongly

16 See, e.g., D. Blumenfeld, ‘Leibniz’s Theory of the Striving Possibles’, in Woolhouse (ed.),Leibniz: Metaphysics and the Philosophy of Science, pp. 77–88.



suggested by works such as the Monadology and the Principles of Nature andof Grace which were not published until after his death.

We are now in a position to see that there is more internal coherence toLeibniz’s position on causality than has sometimes been allowed. In the firstplace, there is no tension between Leibniz’s denial of intersubstantial causalityand his admission of such causality in the case of God; when Leibniz deniesthat finite substances can act on one another by influx, he is denying some-thing very different from what he upholds when he asserts, as he sometimesdoes, divine influx on created substances; the term ‘influx’ is used equivocallyin the two cases. Further, and more controversially perhaps, we can also seethat Leibniz’s admission of intrasubstantial causality is not in danger ofsuccumbing to the same arguments which rule out the possibility of causalinteraction between finite substances. The reason why finite intersubstantialcausality is objectionable is that it involves the transference of accidents;however, no such transference occurs in the case of immanent causality,since it is modelled on divine creation. Further, the fact that divine creationis a model supplies positive reasons for holding that such immanent causalityis at least metaphysically and physically possible. For, as a theist, Leibnizbelieves that the fact of divine creation can be conclusively established; itseems reasonable, then, to infer that any form of causality which is modelledon divine creation must be at least both metaphysically and physically pos-sible. Both a posteriori considerations, and the theological doctrine that man ismade in the image of God, then lend some support to the thesis that suchcausality is actual as well.

Near the beginning of this essay I compared and contrasted Leibniz’sposition on causality with that of Malebranche; we saw how though theyagreed in holding that God is the only true intersubstantial cause, theydisagreed inasmuch as Leibniz allowed for the existence of genuine immanentcausality as well. Perhaps it would be more illuminating to characterize thedifference by saying that whereas for Malebranche God is the only true cause,for Leibniz all true causality is either divine creation or modelled on divinecreation. But the most interesting moral to be drawn from the comparison isnot a purely exegetical one. For all its elaborate theological setting, Male-branche’s theory of causality proved philosophically fruitful; as is now wellknown, it leads straight to Hume. By contrast, Leibniz’s account of causalityleads nowhere. The real weakness with Leibniz’s position on causality is notthat it lacks internal coherence but that it is a philosophical dead end.



11

Leibniz and the Causal Self-Sufficiencyof Substances1

In the Monadology Leibniz writes:

We could give the name entelechy to all simple substances or created monadsbecause they have within them a certain perfection: there is a kind of self-sufficiency (autarkeia) which makes them sources of their own internal actions,or incorporeal automata, as it were.

(Monadology 18, G VI 609–10; WF 270)

The idea that substances are in some sense causally self-sufficient or sources oftheir own states is one that strikes deep roots in the Aristotelian tradition; it isalso one that is taken over by Descartes in his Principles of Philosophy anddeveloped by Spinoza in the Ethics. Leibniz’s commitment to the thesis is clearand is part of his ownAristotelian legacy, but it may be thought that he is not ina position to maintain the thesis in an unrestricted form. It is tempting tosuppose that Leibniz is under pressure fromChristian theology, for instance, touphold only a qualified version of the doctrine. Yet in the passage from theMonadology Leibniz states the doctrine without any qualification. In this essayI seek to argue that Leibniz was justified in stating the doctrine in this way: thereis a perfectly good sense in which, for Leibniz, substances are indeed endowedwith unrestricted causal self-sufficiency. I shall defend this thesis against twochallenges. In the first part of the paper I shall defend it against the traditionalSpinozistic objection that unrestricted self-sufficiency is inconsistent withLeibniz’s commitment to created substance. In the last two sections of theessay I shall consider a more modern version of the challenge which maintainsthat the causal self-sufficiency of Leibnizian substances is restricted to their

1 Earlier versions of this essay were read at a colloquium at Hampden-Sydney College,Virginia; the Margaret Wilson Memorial Conference at the University of California, SanDiego; and a conference on Liberty and Causality in Seventeenth-Century Philosophy at LesAvants, Switzerland. I am grateful to the audiences on all three occasions for their helpfulcomments. I am particularly grateful to Paul Rateau, my commentator at Les Avants, for hisvaluable criticisms and suggestions.


non-initial states. As we shall see, it will be necessary to employ rather differentstrategies for meeting the two challenges. In each case, however, my defence ofthe thesis will involve heavy use of distinctions between ontological levels.

For the purposes of simplification I shall bracket two puzzling and disputedissues concerning Leibniz’s theory of substance. Recent scholarship has beenmuch agitated over the question of how far Leibniz’s metaphysics developedafter the Discourse on Metaphysics; in particular, scholars have wonderedwhether and how far the theory of monads is at least implicit in that workand related writings. Whatever the truth on that issue, in this essay mydiscussion of Leibniz’s theory of substance will be directed at the doctrine ofmonads. Secondly, there has been some, though much less, discussion of theissue whether God himself is a monad for Leibniz. To some readers this mayseem like a merely verbal dispute rather than a substantive one. But again,whatever the truth on this matter, for the purposes of this essay I shall notenter into the issue and shall simply reserve the term ‘monad’ for simplesubstances other than God.

I

Of all philosophers Spinoza is perhaps the one who insists most strongly onthe causal self-sufficiency of substance. Indeed, his commitment to this thesisin an extreme form plays a central role in his attempt to prove substancemonism. Proposition 6 of Part I of the Ethics asserts that one substance cannotbe produced by another substance. In the proof of the next propositionSpinoza infers from this, in conjunction with an unstated version of thePrinciple of Sufficient Reason, that substance is self-caused. On this basis, ifhe had survived to encounter Leibniz’s later metaphysics, Spinoza could havemounted a major challenge to the thesis that Leibnizian monads are causallyself-sufficient: such self-sufficiency is inconsistent with their status as entitieswhich have been created by God. Indeed, for Spinoza, the fact that Leibnizianmonads are created by God is fatal to their pretensions to genuine substanti-ality; famously, for Spinoza, the very idea of created substance is incoherent.

‘Spinoza would be right if there were no monads’ (G III 575; L 663). Leibniz’sremark to Bourguet shows that he is well aware of the need to position hissystem against Spinoza and to respond to the kinds of challenges that Spinozawould mount; it also shows that Leibniz was confident that his system has theresources to respond to such challenges. Further evidence shows that Leibnizwas well aware of Proposition 6 of Spinoza’s Ethics and of the consequenceswhich Spinoza draws from it. Indeed, Leibniz’s responses to Spinoza’s teachingsin this area are remarkably consistent over time: from his first reading of theEthics to mature works such as the correspondence with De Volder, the position



which Leibniz takes up with regard to Spinoza remains essentially the same. Inthe early notes on the Ethics Leibniz remarks that Proposition 6 does indeedfollow from Spinozistic premises, but he goes on to challenge the premises: inparticular, Leibniz indicates that he does not accept the full Spinozistic defin-ition of substance: although Spinoza is of course right that substance is in itself,he is wrong to say that it is also conceived through itself:

I grant the demonstration if substance be taken as something which is conceivedthrough itself. The case is different if substance is taken to be something that is initself, as this is commonly understood, unless he shows that to be in itself and tobe conceived through itself are the same thing.

(G I 142; L 199)

If substance is defined in more traditional fashion as that which is in itself, orin other words as ultimate subject of predication, then the argument does notgo through.In the correspondence with De Volder, which is often seen today as the

canonical expression of Leibniz’s mature metaphysics, Leibniz adopts a similarattitude to the Spinozistic definition of substance from which Proposition 6 isderived. Leibniz had invited De Volder to join him in an enquiry into thedefinition of substance so that he could overcome De Volder’s scepticismabout the thesis that substances are essentially active. When De Volder offeredsuch a definition, Leibniz repeated his objection to the Spinozistic view thatsubstance is by definition conceived through itself which he thought DeVolder was reviving:

Further, beyond the first substance there is (I believe) no substance which can beconceived through itself. But you recognize, I believe, that this is not the onlysubstance but rather therefore that the term ‘substance’ is understood by men insuch a way that there are many substances in the universe. Matter indeed (utique) isnot conceived through itself but through the parts from which it is constituted; butnor are minds as I judge conceived through themselves, since they have a cause andcreatures in general have a connection which arises from the common cause.

(G II 221)

In the next letter Leibniz develops this line of criticism by adding that effectsare best conceived through their causes:

I say this therefore to observe that your notion of substance does not seem to agreeto those things which are commonly so-called but only to the most simple sub-stance. And it is the same when you say substance is that which is conceived throughitself to which I have opposed the opinion that an effect is not better conceived thanthrough its cause, but all substances except the first (prima demta) have a cause.

(G II 225)

Monads are created substances and thus caused by God. Since effects are bestconceived through their causes, they are conceived through God as their


Leibniz and the Causal Self-Sufficiency of Substances 171

creator and therefore not conceived through themselves. (As in his early noteson Spinoza, Leibniz again rejects the Spinozistic definition of substance.)

Throughout his philosophical career Leibniz rejects Spinoza’s definition ofsubstance and thus blocks the argument for the thesis that one substancecannot be produced by another substance: for Leibniz, minds and othermonads are caused or produced by God. Does this mean that Leibniz mustin effect concede that substances have only a limited degree of self-sufficiency?To jump to this conclusion would be a mistake. Consistently, with his recog-nition of created substances, Leibniz can still maintain that there is a perfectlygood sense in which monads enjoy unrestricted causal self-sufficiency, as thepassage from the Monadology suggests. The point can best be made by meansof an analogy deployed by Zeno Vendler:

Think of a writer seeking to ‘eliminate’ one of his characters in the novel he iscomposing. For reasons of his own he prefers a blameless way, death as a result ofan accident, or ‘act of God’. Shall it be an earthquake, storm, fire, or what? Well,he will choose one of these possibilities, and build it into his story. In doing so,however, he cannot just create, say, fire ex nihilo: he has to sketch, or at least allowfor, the antecedents (e.g. how the house caught fire), and weave the wholesequence into the fabric of his story. Did he, the writer, cause the fire? Not atall, the heater’s explosion caused it. Yet it was up to him whether there be a fire atall. His determination, moreover, that there be a fire at some time in the story,remains outside the temporal framework of the novel; one can write a story takingplace in the nineteenth century now.2

As Vendler indicates, the author of the story is in some sense a cause, but thisauthorial causality is consistent with the unrestricted causal self-sufficiency ofthe narrative: within the narrative, every event has a complete causal explan-ation in terms of prior events, such as the heater’s explosion. (Let us bracketfor the moment the issue of the first event in the narrative and the problems itmay pose). It would obviously be a category mistake to offer a causal explan-ation of an event in a novel or a play by invoking the causality of the author.

To bring home the force of this point, consider, for instance, the well-known case of Shakespeare’s The Tempest. It is legitimate to ask why Prosperorenounces his magic and drowns his books at the end of the play. Now weknow that The Tempest is a valedictory play composed near the end ofShakespeare’s career as a dramatist: in some sense in this play Shakespearehimself is saying farewell to his own brand of magic, if you will. But no readerwould be satisfied by an answer to a question about Prospero’s action whichappealed to Shakespeare’s valedictory intentions: this would rightly be seen asa case of confusing two levels. The appropriate kind of answer would appeal tosuch things as the fact that Prospero has come to see that ‘The rarer action is in

2 Z. Vendler, The Matter of Minds (Oxford: Clarendon Press, 1984), p. 119.



virtue than in vengeance’; as a result he no longer needs his magic in order tocontrol and avenge himself on the men who wronged him years before. Andyet it is still perfectly true to say that Shakespeare is the cause of the dramaticnarrative; it was up to Shakespeare whether Prospero should renounce hismagic.How this analogy helps to illuminate the autarkeia of created substances in

Leibniz’s metaphysics should, I think, be clear. Just as the author is the cause ofthe play or novel, so God is the cause of the realm of created substances. But tosay this is not to detract from the causal self-sufficiency of the created realm,for just as every event in the play or novel is to be explained in terms of theevents within the narrative, so every state of a created substance is to beexplained in terms of other states of those substances; indeed, for Leibniz,every such state is to be explained in terms of prior states of the samesubstance. It is in this sense that, for Leibniz, all simple substances areendowed with unrestricted causal self-sufficiency. It would obviously be amistake to seek to explain why a simple substance comes to be in a certainstate by appealing to the causal activity of God. To do so would be to committhe error of confusing distinct ontological levels. It is indeed this distinctionbetween ontological levels that is the key to seeing how divine creation doesnot detract from the causal self-sufficiency of monads.

It must be admitted that, in its application to Leibniz’s metaphysics, theanalogy between God and author is in one way imperfect.3 Authors typicallyinvent the narratives of plays and novels; they create characters and plots, anddecide on the role that the characters are to play in the plot. By contrast,Leibniz’s God does not strictly invent the narrative of the world he creates.A possible world for Leibniz is a maximal set of compossible essences that Godfinds in his intellect; it does not depend on the divine will. Thus in creating thebest possible world God’s role is limited to actualizing a set of compossibleessences. In a word, God is the author of existences; he is not the author ofessences. But this imperfection in the analogy does not undermine its ability toilluminate the autarkeia of created substances. The important point is that theanalogy holds with regard to the issue of causal explanation: in the case ofcreated substances, as in the case of novels or plays, such explanations mustrespect the differences in ontological levels.Let us conclude this section by returning to the comparison between Leibniz

and Spinoza. One way of reading Leibniz is to see him as offering the trueaccount of the self-sufficiency of substances against Spinoza’s perversion of thedoctrine. For it is one of Leibniz’s main complaints against Spinoza that he isguilty of the fallacy of equivocation. In his early notes on the Ethics hecomplains that Spinoza switches back and forth between his technical sense

3 I am grateful to Paul Rateau for emphasizing this point in his commentary.



of ‘self-caused’ as that whose essence implies existence and an unspecifiedmore familiar sense (perhaps that of existing by its own power):

Here he is rightly to be criticized for using the term ‘cause of itself ’ sometimes inthe special sense which he has given it in Definition 1 and sometimes in itscommon and popular meaning.

(G I 142–3; L 199)

Leibniz, by contrast with Spinoza, offers an account of the causal self-suffi-ciency of substance which is firmly within the Aristotelian tradition and avoidsthe equivocations of the Spinozistic teachings.

I I

Some readers may be willing to grant that there is a sense in which Leibniz’srecognition of divine creation is consistent with a commitment to the unre-stricted causal self-sufficiency of created substances. But they may object thatthere are other reasons why Leibniz cannot maintain such unrestricted causalself-sufficiency. According to this challenge, Leibniz, it may be said, does notsimply hold that monads are created by God; he further holds that God is theimmediate cause of the initial states of substances. Thus when Leibniz saysthat monads are self-sufficient or that all their states arise out of their owndepths, he must be understood to be thinking of only their non-initial states.Such an interpretation has been defended in modern times by Robert C. Sleighwho construes Leibniz’s doctrine of spontaneity, as he calls it, in these terms:according to Sleigh, ‘every non-initial state of a substance has as its real causesome preceding state of that substance’.4

One might wonder whether there is any textual evidence for the Sleighinterpretation. To this the answer is perhaps surprisingly ‘yes’. In correspond-ence with Arnauld Leibniz seems not only to commit himself to the existenceof first states but also to treat them as exceptions to the spontaneity thesis injust the way that Sleigh envisages:

Everything happens to each substance as a consequence of the first state that Godgave to it in creating it, and, extraordinary concourse apart, his ordinary con-course consists only in the conservation of the same substance, in conformitywith the preceding state and the changes it brings about.

(G II 91; AG 82)

4 R.C. Sleigh, Leibniz and Arnauld: A Commentary on their Correspondence (New Haven:Yale University Press, 1990), p. 130. Leibniz’s doctrine of spontaneity has recently been discussedin connection with the issue of human freedom by two scholars: Michael Murray, ‘Spontaneityand Freedom in Leibniz’, in Rutherford andCover (eds.), Leibniz: Nature and Freedom, pp. 194–216,and Donald Rutherford, ‘Leibniz on Spontaneity’, in the same volume, pp. 156–80.



Superficially read, this passage suggests what we might call the ‘domino model’of divine and intrasubstantial causality: God causes the first state of a createdsubstance rather in the way that someone applying pressure to the firstdomino in a series causes it to topple over. However, each subsequent stateof a created substance or monad is really caused by a prior state of the samesubstance, just as the collapse of every non-initial domino is caused bypressure from its neighbour. On this reading God causes the first state ofcreated substances immediately, but is at most only a remote cause of allsubsequent states; such states have as their proximate causes some precedingstate of the monad.But this cannot be the right way of reading what Leibniz has in mind, for it

takes no account of Leibniz’s views on the nature of divine concurrence. (It istrue that the letter to Arnauld rather underplays this doctrine, but it does notentirely ignore it.) Consider again the case of the author writing a play. As wehave seen, if we choose to say that the author is a cause at all, we mustrecognize that his authorial causality operates on a higher level than the eventsof the narrative. And this higher-level, authorial causality operates equallywith regard to all the events of the narrative: it is not as if God stands in acausally privileged relationship to the first event. If Shakespeare is in somesense the cause of the storm in the first scene of The Tempest, he is just asmuch, and in the same way, the cause of Prospero’s decision to renounce hismagic and to forgive his enemies. It is not as if Shakespeare could create thestorm scene and then let the rest of the narrative take care of itself as a causalsequence of which he was only the remote cause. Perhaps in the case ofparticularly vivid characters and plot situations we may sometimes speak inthese terms. We might say, for instance, that once Shakespeare had imaginedMacbeth’s encounter with the witches on the heath, he did not need to doanything more: he could simply let the narrative unfold by virtue of its owninner logic. But this of course is merely a manner of speaking: it is a way ofdrawing attention to the artistic rightness and apparent effortlessness of theauthor’s creation. There is, then, no real sense in which the author’s relation-ship to a first event is causally privileged.When we turn to Leibniz’s view of divine concurrence we find that the

analogy with authorial causality holds. It is true that in the letter to Arnauld,Leibniz tends rather to play down the importance of divine concurrence, butelsewhere Leibniz insists on it: he explains that God concurs to the world byconserving it, and that divine conservation is only conceptually distinct fromcreation. In the Vindication of God’s Justice Leibniz writes, for instance:

There is a sound doctrine which teaches that this divine preservation in existenceis a continued creation—comparable to the rays continually emitted by the sun—although the creatures do not emanate from the divine essence nor emanatenecessarily.

(G VI 440)



In the Theodicy itself Leibniz spells out the point that later states of createdsubstances are as much causally dependent on God as the states at thebeginning:

What can be said for certain on the present subject is that the creature dependscontinually on divine operation, and that it depends on it no less after the time ofits beginning than when it begins. This dependence implies (porte) that it wouldnot continue to exist if God did not continue to act; in short, this action of God isfree. For if it were a necessary emanation, like that of the properties of the circle,which issue from its essence, it must then be said that God in the beginningproduced the creature necessarily, or else it must be shown how in creating itonce, he imposed on himself the necessity of conserving it. Now there is noreason why this conserving action should not be called production, and evencreation if one wishes. For the dependence being as great in the succeeding statesas in the beginning, the extrinsic denomination of being new or not does notchange the nature of that action.

(Theodicy 385, G VI 343–4; H 355–6; translation modified)

Leibniz’s doctrine of divine conservation thus implies that the analogy be-tween God and created substances on the one hand and the author and hisnovel on the other holds even here. The author is equally the cause of all theevents in the narrative; in the same way God is equally the cause of all thestates of substances. None of these states are causally privileged.

Let us summarize the results of the discussion so far in this section. Ifmonads have first states, then these states are causally related to God in thesame way as all subsequent states; they are dependent on God as creator. Butthis leads to a difficulty: as Cover and O’Leary-Hawthorne note, it is hard tosee how a first state which is caused by God can be said to arise from itsdepths.5 With respect to subsequent states we can explain this claim by sayingthat each such state is really caused by a prior state of the substance, and wehave seen how such causality is consistent with divine causality by invokingthe difference of ontological levels. But if there are first states of monads, thenex hypothesi there are no earlier states of the same monads to which we canappeal to explain how all their states arise from their depths. And unless thereis a cause on the lower ontological level, it will not be true to say that createdmonads are unrestrictedly self-sufficient. Thus the problem is not one ofreconciling divine creation with the causal self-sufficiency of monads; it israther one of explaining how every state of a monad, including the first one,arises from its depths. At the lower ontological level, the first states seem to beleft causally dangling. One could perhaps maintain that such a situation isconsistent with the demands of the Principle of Sufficient Reason; thedemands of this principle are satisfied inasmuch as the first state is explained

5 J.A. Cover and J. O’Leary-Hawthorne, Substance and Individuation in Leibniz (Cambridgeand New York: Cambridge University Press, 1999), p. 232.



by divine causality. But philosophically the notion of a causally dangling firststate is most unappealing.The idea that created substances or monads have first states is thus philo-

sophically problematic. But is Leibniz really committed to such a claim? Wehave seen that in correspondence with Arnauld, Leibniz does indeed seem toaffirm this doctrine. But there is a fascinating and little-known exchange withBourguet towards the end of Leibniz’s life which offers a particularly cleardiscussion of alternative views and shows that Leibniz is not committed to thethesis he defends in reply to Arnauld. Although he makes no explicit referenceto monads, he does directly address the question of whether the universe has abeginning or first instant. Leibniz’s immediate concern in context is with theLeibnizian-sounding question whether the universe’s level of perfection isconstant over time. Availing himself of geometrical examples, Leibniz identi-fies two main hypotheses and divides the second into two sub-hypotheses:

Two hypotheses can be formed—one that nature is always equally perfect, theother that it always increases in perfection. If it is always equally perfect, though invariable ways, it is more probable that it had no beginning. But if it alwaysincreases in perfection (assuming that it is impossible to give it its whole perfectionat once), there would still be two ways of explaining the matter, namely, by theordinates of the hyperbola B or by that of the triangle C. According to thehypothesis of the hyperbola, there would be no beginning, and the instants orstates of the world would have been increasing in perfection from all eternity. But,according to the hypothesis of the triangle, there would have been a beginning.The hypothesis of equal perfection would be that of rectangle A.

(G III 582; L 664)6

Notice, then, that of the three hypotheses Leibniz entertains, only one of thementails that the world has a beginning; of the remaining two, one actuallyexcludes a beginning and the other renders it improbable. Of course, whiledistinguishing three logically possible hypotheses, it is still open to Leibniz to saythat there are conclusive grounds for preferring one of them—for instance, thatthe world has a beginning. But surprisingly Leibniz fails to do so; in fact he saysthat he does ‘not yet see any way of demonstrating by pure reasonwhich of these[hypotheses] we should choose’ (G III 582; L 664). In a later letter Leibniz insists,contra Spinoza, that the series of things is contingent and that one state does notfollow necessarily from another. But he still wants to emphasize that it does notfollow from the contingency of the series that the universe has a beginning. Thisissue remains simply undecidable by pure reason.Leibniz’s late correspondence with Bourguet, then, offers particularly clear

evidence that he is at least prepared to entertain the idea that the universe hasno beginning in time. And in view of his other commitments this means that

6 I am grateful to John Whipple for drawing my attention to this passage.



he is also at least prepared to entertain the idea that no substance has a firststate, at least naturally; for Leibniz holds that (miracles apart) no substancecomes into existence in the course of nature. Thus Leibniz has the resources tooffer an elegant theory of how created substances can be causally self-suffi-cient. Every state of a substance has as its real cause a prior state of thatsubstance, and so on to infinity: in this way it is true without qualification thatevery state of a substance arises out of its own depths. Such a thesis would bereminiscent of Spinoza’s Ethics I P28. It is true, of course, that unlike Spinoza,Leibniz holds that substances are created by God, but as we have seen, thedoctrine of divine creation is consistent with monadic autarkeia, since divinecreation, like authorial causality, operates on a higher ontological level. More-over, the doctrine of divine creation is also consistent with the eternity of theworld. As Leibniz explains in On the Ultimate Origination of Things:

Even if you suppose the world eternal, as you will still be supposing nothing but asuccession of states and will not find in any of them a sufficient reason, norhowever many states you assume will you advance one step towards giving areason, it is evident that the reason must be sought elsewhere. . . . From this it isevident that even by supposing the world to be eternal we cannot escape theultimate, extramundane reason of things, or God.

(G VII 302; P 136–7)

In this work, then, Leibniz recognizes that provided the eternal series iscontingent, there is a need for an outside cause or reason to explain whythis infinite series exists rather than some other.

Perhaps for theological reasons Leibniz, thus, does not unequivocally opt forthe doctrine that the universe has no beginning. And his reluctance to do somay seem disappointing, for this approach provides him with such an elegantsolution to the problem of causal self-sufficiency. But suppose that Leibniz doesacknowledge that the universe has a beginning. He can still explain howmonads are causally self-sufficient by invoking his doctrine of the strict atem-porality of monads. Leibniz could say that while at the phenomenal level theseries has a temporal beginning, it has no such beginning at the ground floormetaphysical level. Strictly speaking, monads are neither in time nor space.7

The distinction between the phenomenal and the ground levels provides thekey to solving, or rather dissolving the puzzle raised by Cover and O’Leary-Hawthorne. Cover and O’Leary-Hawthorne wonder how Leibniz can say thatall states of a created substance arise out of its own depths if there is a first statethat is provided by God. The answer, I suggest, is that it is only at the groundfloor, monadic level that all states of a substance arise out of its own depths.

7 Hartz and Cover have challenged the view that space and time are phenomenal for Leibniz,but not in such a way as to deny that they are not found at the ground floor metaphysical level.See G. Hartz and J.A. Cover, ‘Space and Time in the Leibnizian Metaphysic’, Nous 22 (1988),493–519.



Since, strictly speaking, there is no time at this level there is no temporally firststate. Hence there is no problem of reconciling the claim that substances havefirst states provided by God with the thesis that all their states arise out of theirown depths.Before we conclude this section it is worth noting one further option that the

distinction between levels makes available to Leibniz; it is perfectly possible forLeibniz to say both that at the phenomenal level the world has no beginning intime and that at the ground level it is strictly atemporal. In many ways thiswould be an attractive position to hold. But notice that if Leibniz commitshimself to saying that the world has no beginning at the phenomenal level,there is no need for him to invoke monadic atemporality in order to solve theproblem of causal self-sufficiency. The need to invoke this doctrine arises fromthe supposition that at one level the world may indeed have a first state.

I II

The thesis that monads are strictly atemporal thus suggests a solution to theproblem of the first state.8 But some readers may be inclined to doubt whetherLeibniz is really committed to the doctrine of the atemporality of monads. Inone way such scepticism is surprising: it is agreed on all sides that space is notto be found at the ground floor of Leibniz’s metaphysics; it is also widelyagreed that Leibniz tends to treat time and space as metaphysically on a par(see e.g. Leibniz’s Fifth Paper to Clarke, G VII 402–3; P 233). But those whoquestion the strict atemporality of monads may reply that Leibniz did notdevelop his views on time as fully as his views on space.9 Moreover, it may befelt that the doctrine of the strict atemporality of monads is inconsistent withsome of the properties that Leibniz wishes to ascribe to them.10 In whatfollows I offer a somewhat speculative interpretation that suggests that Leibnizcan indeed maintain the atemporality of monads consistently with his claimsabout their basic properties.One attractive way of construing monadic atemporality is in terms of a strict

analogy with God. God, for Leibniz, is obviously outside time altogether; he isan eternal being, and Leibniz is clear that divine eternity is to be understood in

8 The thesis of monadic atemporality has recently been defended by Michael Futch, Leibniz’sMetaphysics of Time and Space, Boston Studies in the Philosophy of Science 258 (Berlin: Springer,2008). Cf. John Whipple, ‘The Structure of Leibnizian Simple Substances’, British Journal for theHistory of Philosophy 18 (2010), 379–410.

9 This is noted by R. McRae, ‘Time and the Monad’, Nature and System 1 (1979), 103–9.10 Rateau observes that Leibniz speaks of monads as having at least possible beginnings:

‘monads can only ever begin or end all at once’ (Monadology 6, G VI 607; WF 268). But of coursea beginning need not be a strictly temporal one.



the Platonic tradition as inconsistent with any temporal predicates. Yet in hisintellect God represents an infinity of possible worlds; in these worlds there areof course temporal sequences of events, at least at the phenomenal level. In thesame way, it might be said, Leibnizian monads timelessly represent the actualworld with its temporal sequence according to their point of view.

Could Leibniz subscribe to such a view of monadic atemporality? In oneway it might seem that he could. For it clearly does justice to one central themeof Leibniz’s thought—that is, the Neoplatonic idea that all created substancesare mirrors of God or of the divine perfections. As Leibniz writes in theDiscourse on Metaphysics:

Each substance is like a whole world, and like a mirror of God, or indeed the wholeuniverse, which each one expresses in its own fashion—rather as the same town isdifferently represented according to the different situations of the personwho looksat it. In a way, then, the universe ismultiplied asmany times as there are substances,and in the same way the glory of God is redoubled by so many quite differentrepresentations of his work. In fact we can say that each substance in some waycarries the imprint of the infinite wisdom and omnipotence of God, and imitatesthem insofar as it is capable of it. For it expresses, albeit confusedly, everythingwhich happens in the universe, past, present, and future, and this has someresemblance to an infinite perception or understanding.

(DM 9, G IV 434; WF 61)

Thus the monad mirrors not only the divine intellect through its manner ofrepresentation but also the divine atemporality (the divine perfection ofeternity). Although the ‘mirror of God’ theme is played down in Leibniz’slater metaphysics, it is, as I have argued elsewhere, never really abandoned.11

This way of understanding the atemporality of monads and their representa-tions harmonizes well with one of the constant themes of Leibniz’s philosophy.But it is natural to object that construing the timelessness of monads in this waymakes it hard to see how monads can be active. And any interpretation whichrules out monadic activity is doomed, for activity is of the essence of substances.But Leibniz at least would have seen noproblemhere, for God is outside time andyet is supposed to be a paradigmatically active being. If atemporality preventedmonads from being active, it would similarly prevent God from being active; andthat, in Leibniz’s eyes, is absurd. In any case, it is clear why Leibniz would notaccept that being in time is a necessary condition of activity. Leibniz holds that tobe active is to be a genuine causal agent, and he surely shares the pre-Humeanview that it is not essential to causes to be temporally prior to their effects.

A more compelling version of this objection is that this way of construingmonadic atemporality cannot do justice to one of their most fundamentalfeatures, namely appetition; this of course is the dynamic principle by virtue of

11 N. Jolley, Leibniz (London: Routledge, 2005).



which they change from state to state. Indeed, it might be said that in so far asLeibniz plays down the ‘mirror of God’ theme in his later philosophy, this maybe in part because he recognizes that there is no analogue in God to appetition.In one way, however, this objection is not as powerful as it seems. As I have

argued elsewhere, even in the case of God, Leibniz arguably recognizes some-thing analogous to appetition.12 In creation God acts to maximize the good; intheir endeavours towards new perceptual statesmonads are similarly seeking tomaximize at least the apparent good. Nonetheless, it is surely correct to feel thatsuch an account leaves out a fundamental difference between divine creationand the appetition of monads: employing the distinction that Descartes madefamous in the Third Meditation, we could say that appetition belongs tomonads at the level of formal or intrinsic reality, not objective or representa-tional reality.13 The point is somewhat abstract but it can be illustrated throughthe familiar example of a film. At the level of representational content orobjective reality there will be a kind of dynamic principle; in other words,there will be some thing or set of things which makes the story move forward.The obvious candidates here are the motives of the characters, in conjunctionwith the circumstances in which they find themselves. It is by virtue of thisdynamic principle that the plot of Anna Karenina unfolds. But there is adifferent kind of dynamic principle by virtue of which one frame of a film issucceeded by another; here, of course, reference is made to the properties of theprojector and the activity of the projectionist. It is clearly by analogy with thissecond level that monadic appetition should be understood. Thus it may seemthat the strict ‘mirror of God’ approach to monadic atemporality cannot dojustice to appetition.Perhaps the best way of dealing with this problem involves returning to the

idea of an infinite series. Since, as we have seen, monads are outside time (withregard to their intrinsic properties), such an infinite series is not of course atemporal sequence. Nonetheless, it is a genuine causal sequence in which eachstate of a monad is produced by another state in accordance with the principleof appetition. Once again, it will not do to object that if the sequence is nottemporal, it cannot be causal; for such an objection depends on a Humeanconception of causality which has no place in connection with Leibniz or, forthat matter, Spinoza.The idea that there is an infinite series of monadic states is open to one final

objection. According to this interpretation, the realm of phenomena may besaid to have a beginning, but the realm of monadic states does not. Now

12 See chapter 10 in this volume.13 For further discussion of the application of the distinction between formal and objective

reality to Leibniz’s metaphysics, see R.M. Adams, ‘Phenomenalism and Corporeal Substance inLeibniz’, in French, Uehling, and Wettstein (eds.), Contemporary Perspectives on the History ofPhilosophy, Midwest Studies in Philosophy VIII (1983), 217–57, esp. 218–22.



Leibniz surely wants to say that these two realms express one another. It maybe wondered whether this can be the case if one realm is finite and the otherinfinite. But it is clear that Leibniz would not face any problem of consistencyhere. For Leibniz recognizes that finite beings can express the infinite sub-stance God; God also expresses each finite substance by way of perceiving it.

In this essay I have tried to show that Leibniz has the resources to defend histhesis that created substances are endowed with a kind of self-sufficiency thatmakes them sources of their own internal actions. The strategy of argumentadopted depends on making distinctions between ontological levels; the dis-tinction between divine or authorial causality on the one hand and creaturelyor narrative causality on the other needs to be supplemented by a furtherdistinction within the created world between the phenomenal and monadiclevels. It is true that I have arguably left some puzzles unsolved. In the firstplace, on the assumption that at least phenomenally the world has a temporalbeginning, Leibniz may be confronted with a dilemma: either the first state iscaused by God, in which case the distinction between levels is blurred, or it hasno cause, in which case the Principle of Sufficient Reason is violated. More-over, the attempt to reconcile strict monadic atemporality with a recognitionof an infinite series of monadic states runs the risk of introducing panlogicism;that is, recognizing logical links at the ground floor of Leibniz’s metaphysics.Now, as I have suggested, these problems can be avoided if Leibniz optsstraightforwardly for the thesis that the universe has no temporal beginning.Although Leibniz entertains such a thesis, perhaps out of theological cautionhe is reluctant to embrace it fully. This seems to be another case where a fullycoherent Leibniz would come close to embracing Spinozism.



12

Leibniz and Phenomenalism

Did Leibniz become a phenomenalist in his later years? Since Furth’s pioneeringpaper ‘Monadology’,1 most scholars would no doubt agree that Leibniz at leastflirted with phenomenalism, and some would go further; thus Louis Loebsuggested that Leibniz finally came to espouse the phenomenalist option.2 Inthis essay I wish to challenge Loeb’s claim. I shall not deny that Leibniz statedphenomenalist ideas on occasion, but I shall argue that he never fully adoptedthem; on the contrary, he continued to hold the rival thesis that bodies are insome sense aggregates of monads or simple substances. This conclusion raisesproblems of its own, for as we shall see, in crucial respects phenomenalism lookslike the more attractive option. I shall therefore seek to explain why Leibniz’sflirtation with phenomenalism never developed into a serious commitment.

I

‘Phenomenalism’ is a slippery term, and it is clear that a number of differentpositions have gone under this label. Since the beginning of the twentiethcentury the dominant version of phenomenalism has been linguistic: modernphenomenalists typically assert that physical-object statements are translat-able into statements about sense-data; equivalently, physical objects are said tobe logical constructions out of sense-data. On this interpretation, phenomen-alism is not presented as a metaphysical thesis about the world. But it wouldbe anachronistic to look for a purely linguistic version of phenomenalism in aseventeenth-century philosopher.3 When scholars debate whether Leibniz is aphenomenalist, they are surely asking whether he holds a certain metaphysical

1 M. Furth, ‘Monadology’, in Frankfurt (ed.), Leibniz: A Collection of Critical Essays,pp. 99–135.

2 See L. Loeb, From Descartes to Hume: Continental Metaphysics and the Development ofModern Philosophy (Ithaca, NY and London: Cornell University Press, 1981), ch. 7, pp. 303–9.

3 Cf. M. Hooker and M. Pastin, ‘Leibniz and Duhemian Compatibilism’, in Hooker (ed.),Leibniz: Critical and Interpretive Essays, p. 328; and Ian Hacking, ‘Individual Substance’, in


thesis about the nature of physical objects. What is in question is whether,according to Leibniz, physical objects are reducible to sets of perceptions. Forthe purposes of this essay, this is how I shall understand the issue.

Phenomenalism, on this interpretation, may be contrasted with idealism.Whereas phenomenalism is an answer to a question in the philosophy ofmatter, idealism is an answer to a more general question: what are the funda-mental building-blocks of reality? Idealists answer this question by claimingthat the ultimate substances or entities are souls or at least soul-like. Idealismthus provides an answer to the most basic of all metaphysical issues. I do not ofcourse claim that idealism and phenomenalism have always been distinguishedin precisely this way, but the distinction is a real one, and whatever labels areused to capture it, it is important for our present issue.4

The logical relationship between phenomenalism and idealism can bebrought out in the following way. A philosopher may be both an idealist anda phenomenalist. Berkeley, for example, is an idealist inasmuch as he holds thatonly spirits are substances, and he is a phenomenalist inasmuch as he holdsthat bodies or sensible things are collections of ideas; one might say that, forBerkeley, bodies are adjectival on spirits. But though idealism is consistent withphenomenalism, it does not of itself entail it. The idealist, like the phenomenal-ist, must of course deny that bodies are substantial, for he is committed by hisidealism to holding that the only substances are souls or soul-like. But it is amistake to suppose that he is necessarily committed to giving a phenomenalistaccount of physical objects. Phenomenalism, rather, is one option amongseveral that are open to him. Consistently with his idealism, for example, hemay eliminate bodies altogether, or he may hold that bodies are in some sensecollections of souls. It is just this last option which is important in connectionwith Leibniz. In his later writings Leibniz is certainly an idealist, but it is not atall clear how far he opts for the phenomenalist account of the status of bodies.

The distinction between phenomenalism and idealism is thus clearly im-portant for the understanding of Leibniz. Unfortunately, however, Leibnizscholars have sometimes conflated the two positions. Parkinson, for example,argues that Leibniz only ‘toyed’ with phenomenalism, but although this con-clusion seems the right one, he appears to reach it by an unsatisfactory route:

There were indeed times when Leibniz toyed with phenomenalism, suggestingthat to talk about physical things is only to talk about perceptions. The idea whichhe puts forward is that physical things might be ‘true phenomena’—that is, thateach physical thing is simply a coherent set of the appearances present to a soul or

Frankfurt, Leibniz, p. 141: ‘Today phenomenalism is pap about the analysis of words. It was oncea strong claim about the world.’

4 A different account of the distinction is given by Jonathan Bennett, Locke, Berkeley, Hume:Central Themes (Oxford: Clarendon Press, 1971), pp. 135–9.



souls. However, the idea is put forward only to be rejected, Leibniz arguing that itcan be proved that there exist physical things as well as souls.5

In this passage Parkinson seems to move from the question of whether Leibnizis a phenomenalist to the question of whether he is an idealist. In other words,he does not sharply distinguish between: ‘Does Leibniz regard bodies as sets ofperceptions?’ and ‘Does Leibniz hold that the only substances are souls?’ Inorder to show that phenomenalism is not Leibniz’s considered view, he seemsto deny that he is even an idealist. For if Leibniz holds that ‘there exist physicalthings as well as souls’, and if this means that physical objects are ontologicallydistinct from souls, then souls are not the only substances. And this is justwhat idealism denies.Parkinson’s apparentwillingness to deny that Leibniz is an idealist seems a high

price to pay for holding that he is not a phenomenalist. It can be hardly doubtedthat in his later writings Leibniz is an idealist, claiming that the only substances aresouls. In a famous passage he tells De Volder: ‘indeed, considering the mattercarefully, itmay be said that there is nothing in theworld except simple substancesand, in them, perception and appetite’ (G II 270; L 537). Such a statement is asidealist as one couldwish. It certainly seems impossible to reconcile with the claimthat ‘there exist physical things as well as souls’. The puzzle posed by Parkinson’sinterpretation is partly solvedwhenwe examine his textual support; it consists of aquotation from the Eclaircissement du Nouveau Système:

I am asked why God does not content himself with producing all the thoughtsand ‘modifications’ of the soul, without these ‘useless’ bodies which the soul, it issaid, can neither ‘move’ nor ‘know’. The answer is easy. It is that God willed thatthere should be more rather than fewer substances, and that he found it good thatthese ‘modifications’ should correspond to something external.

(1696, G IV 495)

But this work dates from a period before Leibniz’s decisive move to monadol-ogy;6 at this time Leibniz still seems to regard corporeal substances as onto-logically basic entities. Thus the Eclaircissement cannot be used to settle aquestion concerning Leibniz’s mature position on the ontological status ofbodies. Yet Parkinson does not suggest that the quotation is less than a reliableguide to Leibniz’s later views. Like other commentators, Parkinson tends toignore the continuing development of Leibniz’s system.A further difficulty with Parkinson’s account is that it seems to pack too

much into the principle of the best. According to Parkinson, Leibniz appeals

5 G.H.R. Parkinson, Logic and Reality in Leibniz’s Metaphysics (Oxford: Clarendon Press,1965), p. 166. Cf. pp. 190–1.

6 I agree with Broad in locating this change in the letters to De Volder which extend from1699 to 1706. See C.D. Broad, Leibniz: An Introduction (Cambridge: Cambridge UniversityPress, 1975), p. 88.


Leibniz and Phenomenalism 185

to this principle in order to argue that bodies are ontologically distinct fromsouls; in this sense it is said to provide the answer to Berkeley.7 Now Parkinsonseems right that there is at least an implicit appeal to the principle of the best inthe above passage. The principle of the best states, very roughly, that reality is asrich as possible, and it is plausible to suppose that God is acting in accordancewith this principle when he wills that ‘there should be more rather than fewersubstances’. But it is a mistake to suppose that the principle of the best has anybuilt-in tendency to exclude idealism. The principle requires that there be morerather than fewer substances, but it does not of itself determine the nature ofthose substances. Even when Leibniz has made the move to outright monadol-ogy, he can still find a role for the principle without changing its content; forhe seems to appeal to this principle when challenged to explain why the numberof monads is infinite: ‘You ask further: why actually an infinity of monads?I reply that the mere possibility of an infinity is enough to establish this, since itis manifest how very rich are the works of God’ (to Des Bosses, 20 September1712, G II 460; L 607). A good God will want to subscribe to a richness-maximizing principle, and within an idealist framework this is satisfied bycreating an infinity of monads. Parkinson is right that the principle of thebest bears on the question of why Leibniz is not Berkeley, for it is this principlewhich leads Leibniz to insist that the number of souls is infinite. But Parkinsonfails to see that there is a sense in which the principle is neutral with respect toidealism. If, in the Eclaircissement, Leibniz holds that there are bodies as well assouls, it is because of other considerations than the principle of the best.

My basic criticism of Parkinson, then, is that he provides too quick ananswer to the question of whether Leibniz is a phenomenalist. On the strengthof the Eclaircissement he denies that Leibniz is an idealist, and by means ofthe apparent conflation we have examined, he concludes that Leibniz is not aphenomenalist. One consequence of this conflation is that he exaggerates theontological gulf that divides Leibniz from Berkeley. In fact, in spite of theobvious differences, Leibniz and Berkeley share an important characteristic:they are both idealists, holding that souls alone are genuine substances. Butwhether Leibniz is also, like Berkeley, a phenomenalist is an issue that stillremains open.

I I

The Leibniz of the monadological writings claims that ‘there is nothing inthe world except simple substances and, in them, perception and appetite’(G II 270; L 537). Such a thesis tells us about the fundamental building-blocks

7 Parkinson, Logic and Reality, p. 167.



of the universe, but it leaves the status of physical objects unspecified: it doesnot discriminate between eliminative and reductive approaches to the issue.Fortunately, however, Leibniz leaves us in no doubt on this score: he is quiteconsistent in holding that bodies are to be, not eliminated, but reduced. In aletter to De Volder, astonishingly not translated by Loemker, the contrast ismade quite explicit:

I do not indeed eliminate (tollo) body, but I reduce it (revoco) to what it is. ForI show that corporeal mass which is believed to have something beyond simplesubstances is not a substance but a phenomenon resulting from simple substanceswhich alone have unity and absolute reality.

(Undated, G II 275; AG 181)

And in some remarks on Berkeley, Leibniz criticizes him for failing to see thatan idealist metaphysics has no need to eliminate matter: ‘we have no need tosay that matter is nothing, but it suffices to say that it is a phenomenon like therainbow’.8 Leibniz may be less than fair to Berkeley here, for Berkeley wouldno doubt say that while material substance is to be eliminated, corporealobjects ‘in the vulgar sense’ are to be merely reduced. But whatever its meritsas philosophical criticism, Leibniz’s remark is most illuminating about his owngeneral approach to the status of physical objects.Within the framework of his idealism, Leibniz is a reductionist about bodies,

but difficulties arise when we try to spell out the nature of the reduction. Furthand Loeb have observed that not one but two distinctmodels of reduction are tobe found in his writings.9 They agree further that of the two models only oneseems clearly phenomenalist. We shall look at each in turn.The non-phenomenalist model may be conveniently called the ‘aggregate

thesis’. Although it needs considerable refinement, the basic idea here is thatbodies are in some sense reducible to aggregates of monads. Such a thesis issuggested by the following passages:

Mass is . . . a being by aggregation, but from infinite unities.(To Des Bosses, 31 July 1709, G II 379)

[Bread] is a being by aggregation, that is, a substantiated thing resulting frominnumerable monads.

(To Des Bosses, January 1710, G II 399)

8 Translated and quoted in R.M. Adams, ‘Phenomenalism and Corporeal Substance inLeibniz’, in French, Uehling, and Wettstein (eds.), Contemporary Perspectives on the History ofPhilosophy, Midwest Studies in Philosophy 8 (1983), p. 222. The original text was first publishedby W. Kabitz, ‘Leibniz and Berkeley’, Sitzungsberichte der Preussischen Akademie der Wis-senschaften, Phil.-hist. Klasse (XXIX, 1932), p. 636.

9 See, for example, Furth, ‘Monadology’, p. 121; Loeb, From Descartes to Hume, pp. 303–4.A different view is put forward by Adams in ‘Phenomenalism and Corporeal Substance’. Adamsargues that the two models are not incompatible but together form ‘a single, phenomenalistictheory’ (p. 217). I am not persuaded, however, that the theory Adams identifies can really becalled phenomenalistic.



It is significant that Leibniz often prefers to speak of body, not as an aggregate ofmonads, but as a being by aggregation which results from monads. Leibniz’spreference for this way of speaking is probably designed to guard against twomisunderstandings. First, with his talk of aggregates, Leibniz is anxious not toimply that monads are parts of bodies, in the way that a sheep is part of a flock:‘Accurately speaking, matter is not composed of these constitutive unities, butresults from them . . . Substantial unities are not parts, but foundations of phe-nomena’ (to De Volder, 30 June 1704, G II 268; L 536). For Leibniz, the parts ofbodies are themselves physical, and since matter is infinitely divisible, there willbe no part of matter which does not have parts which are themselves smallerbodies. Secondly, Leibniz will be careful to stop short of identifying a body withan aggregate of monads, for in this case he would appear to be vulnerable to anobjection from Leibniz’s Law: the table in front of me has properties which donot belong to individual monads or an aggregate of monads. Instead, Leibnizwould probably say that a particular aggregate of monads appears to an observeras an extended physical object. It is in this sense that a physical object can be saidto be founded in, or to ‘result from’, a monadic aggregate.10 We could perhapscapture at least part of Leibniz’s thought by saying that the facts about physicalobjects accessible to human observers are derivable in principle from a completedescription of the associated aggregate of monads.

Apparently co-existing with the aggregate thesis is the second, phenomenal-istic model. On this view, physical objects are to be reduced, not to aggregatesof monads, but rather to sets of perceptions. As we should expect, the pre-established harmony is employed to guarantee that these perceptions areharmonized, both over time and intersubjectively. As Loeb points out, sucha thesis is strongly suggested by the following passage:

Matter and motion . . . are not so much substances or things as they are thephenomena of percipient beings, whose reality is located in the harmony of thepercipient with himself (at different times) and with other percipient beings.

(To De Volder, 30 June 1704, G II 270; L 537)11

There is additional, less direct evidence that Leibniz contemplated a phenom-enalistic version of reduction. In some comments on the ‘Academic philoso-phers’ Leibniz seems to envisage something like Berkeley’s strategy of refutingscepticism by undercutting it:

10 Cf. Loeb, From Descartes to Hume, p. 304.11 Cf. Leibniz to Des Bosses, 16 June 1712:

Verum est, consentire debere, quae fiunt in anima, cum iis quae extra animam geruntur; sedad hoc sufficit, ut quae geruntur in una anima respondeant tum inter se, tum iis quaegeruntur in quavis alia anima; nec opus est poni aliquid extra omnes Animas vel Monades;et in hac hypothesi, cum dicimus Socratem sedere, nihil aliud significatur, quam nobisaliisque, ad quos pertinent, haec apparere, quibus Socratem sessum intelligimus.

(G II 451–2)



The Academics have argued, not altogether improperly, against what we imagineto be outside of us, that is, outside souls or simple substances (contra ea quaeextra nos id est extra animas aut substantias simplices finguntur), even if theywere improperly understood, or used good arguments badly.

(To De Volder, undated, G II 275–6; AG 181–2)

Again, in a letter to Remond, Leibniz hints at the same strategy:

The Academics have doubted whether [material things] were outside us; whichcan be given a reasonable interpretation, by saying that they would be nothingoutside of perceptions, and that they have their reality from the agreementsof the perceptions of apperceiving substances. This agreement derives from theprinciple of pre-established harmony in these substances . . .

(To Remond, July 1714, G III 623)12

Like Berkeley, Leibniz seems to see how the sceptic’s challenge can be met onhis own ground. We can answer the sceptic by accepting his assumption thatwe have no knowledge of anything beyond perceptions, while denying thatthis leaves room for objective talk of bodies.Leibniz’s insight into the advantages of phenomenalism for refuting scepti-

cism not only aligns him with Berkeley; it also show that it is an exaggeration toclaim, as some scholars have done, that Leibniz’s metaphysics is uninfluencedby epistemological considerations.13 But despite the common insight, it shouldbe admitted that a Leibnizian version of phenomenalism must be significantlydifferent from Berkeley’s. Although they are both idealists, Leibniz does nothold, as Berkeley does, that all souls are spirits; on the contrary, as is wellknown, he believes that there is a hierarchy of infinitely many monads stretch-ing down from self-conscious spirits to baremonads endowedwith a low-gradekind of perception. And since every substance perceives the whole universeaccording to its point of view, a phenomenalistic analysis of a physical objectwill involve reference to the perceptual states of every monad, no matter howobscure and confused its perceptions. A Leibnizian version of phenomenalismis thus stranger than Berkeley’s, but as Furth has observed, the peculiarities ofmonadology are also a source of strength; they allow Leibniz to overcome someof the problems that have faced other phenomenalists. For since Leibniz holdsthat every possible point of view on the phenomena is occupied, he can deliver

12 A puzzling feature of this passage is that it restricts the agreement to ‘apperceivingsubstances’ (‘substances apercevantes’). See p. 190.

13 See R. McRae, Leibniz: Perception, Apperception, and Thought (Toronto and Buffalo:University of Toronto Press, 1976), p. 131:

The status of phenomenon or appearance which Leibniz assigns to body, conceived asextended mass, is not a consequence of any epistemological considerations but owes itsorigins to his concern to find a way out of the ‘labyrinth of the composition of thecontinuum,’ which is essentially a metaphysical problem.

Cf. Hacking, ‘Individual Substance’, p. 143.



the whole content of physical-object statements without leaving the realm ofthe actual; unlike phenomenalists with a less generous ontology, he is notcompelled to resort to subjunctive conditionals.14

On the phenomenalist model, then, physical objects are to be reduced to setsof harmonized perceptions; on the aggregate thesis, by contrast, they are tobe reduced to aggregates of simple substances or monads. Since monads arethemselves perceiving substances, the difference between the two theses maynot be immediately striking. But the following may help to clarify it. On theaggregate thesis, each physical object stands in a privileged relationship to somesub-set of the totality of monads; in other words, for every body there is someaggregate which has the special role of ‘well-founding’ it.15 On the phenomenal-ist model, however, this will not be the case; there will be no sub-set of monadsthat is singled out in this way. For as we have seen, since every substanceperceives the whole universe according to its point of view, a reduction of aphysical object will involve the perceptual states of every monad. As Furth says,Leibniz can ‘interpret statements f that ostensibly assert the holding of actualstates of affairs in the realm of corporeal substances, as statements to the effectthat to every monad it perceptually (consciously or not) is as if f’.16 Monadsdiffer enormously in terms of the clarity and distinctness of their perceptions,but there seems no reasonwhy the perceptions of even the barest monad shouldbe excluded from the scope of the reduction.

Scholars such as Montgomery Furth and Louis Loeb seem right, then, thatwe are faced with two non-equivalent models of reduction. But are they right tosuggest that Leibniz abandoned the aggregate thesis in favour of phenomenal-ism? Such a path of development is tentatively sketched by Furth: ‘As time wenton, Leibniz seems to have moved towards a more straightforwardly phenom-enalistic reduction, particularly in trying to break the literal positioning ofmonads at spatial points.’17 It is asserted much more confidently by Loeb:

It is at this time [June 1704], I believe, that Leibniz sees the basic structure of anaccount of bodies in terms of indivisible monads and their states. Bodies are to bereduced to sets of harmonized perceptions of different substances over time. This

14 Furth, ‘Monadology’, pp. 118–19.15 One problem is what criterion Leibniz would employ for matching up a physical object

with an aggregate of monads. The issue is complicated by certain features of the monadology.Thus, it will not be adequate for Leibniz to say that the relevant aggregate is that from which thefacts about the physical object can be deduced; for since every monad perceives the universeaccording to its point of view, there will be no monad or monadic aggregate of which this will notbe true. Thus, this criterion will not serve to discriminate among aggregates of monads.Unfortunately, Leibniz does not, to my knowledge, explicitly deal with this issue. One possibilityis that Leibniz might exploit his thesis that the physical force of bodies derives from the primitiveforce or appetition of monads. On the significance of this claim for the issue of this essay, seepp. 197–8.

16 Furth, ‘Monadology’, p. 116.17 Furth, ‘Monadology’, p. 122.



was a breakthrough . . .With the basic structure of a phenomenalistic account ofbodies in hand, the mature metaphysics is stabilized in Leibniz’s view.18

According to Loeb, June 1704 marks a decisive shift in Leibniz’s philosophy ofmatter. After this date Leibniz is no longer committed to the thesis that bodiesare aggregates of monads; the phenomenalistic reduction is stabilized as Leib-niz’s mature metaphysical view. Yet, as Furth points out, there are a number ofpassages written after June 1704 which aremost naturally read as expressions ofthe supposedly abandoned aggregate thesis. Indeed Furth’s list of such passagesis not, and does not claim to be, exhaustive.19 Loeb himself seems almost toconcede their existence, and thismakes it a little difficult to know exactly what isthe force of his thesis, or what evidence is needed to falsify it.20 Yet in the oneplace where Loeb does challenge Furth we can answer him directly. Faced withthe evidence adduced by Furth, Loeb objects that in at least one of the citedpassages Leibniz is explicitly discussing organic bodies, and according to Loebthese are a special case. With respect to organic bodies Leibniz continues toretain the aggregate thesis for tactical purposes; for all other bodies purephenomenalism holds.21 Loeb, then, seems to be sceptical as to whether Leibnizcontinues to advance the aggregate thesis for other than organic bodies. Suchscepticism can be easily countered. For there is one passage in the Des Bossescorrespondencewhere Leibniz is explicit that non-organic bodies are aggregatesof substances: ‘But I restrict corporeal, i.e. composite, substance to living thingsalone, that is, organic natural machines only. Other things, according tome, aremere aggregates of substances which I call substantiated things’ (to Des Bosses,29May 1716, G II 520; AG 206).Whether or not this expresses a stable view, it iscertainly a mature one, for it dates from the last year of Leibniz’s life.It does not seem possible, then, to maintain that whenever after 1704 Leibniz

speaks of bodies as aggregates, he is thinking of organic bodies only. In view ofthe apparent evidence of Leibniz’s continuing subscription to the aggregatethesis, how might Loeb defend his position? He might object that althoughLeibniz frequently speaks of bodies as aggregates even after June 1704, it is notclear that this means that they are aggregates of monads or simple substanceseven in the refined sense explained above. Loeb might claim to see significancein Leibniz’s tendency to speak of bodies as beings by aggregation ‘from infiniteunities (ex unitatibus infinitis)’ (to Des Bosses, 31 July 1709, G II 379) or‘resulting from innumerable monads (resultans ex innumeris monadibus)’ (toDes Bosses, January 1710, G II 399). Thus Loeb would perhaps suggest that

18 Loeb, From Descartes to Hume, pp. 304–5.19 Furth, ‘Monadology’, p. 121 n. 30. Furth’s list is derived from the Appendix to B. Russell,

A Critical Exposition of the Philosophy of Leibniz, 2nd edn (London: Allen and Unwin, 1937).The following passages can be added to the list: G II 276; G II 379; G II 444; G II 460; G II 520.

20 Loeb, From Descartes to Hume, p. 305, n. 23.21 Loeb, From Descartes to Hume, p. 306.



there is a distinction to be drawn between being an aggregate of monads andbeing an aggregate frommonads. To say, then, that bodies are aggregates frommonads would be only to say that bodies result from monads, and it might beargued that this claim is consistent with the phenomenalistic reduction: if weask what bodies are aggregates of, the answer is ‘perceptions’. Now Leibniz, tomy knowledge, never uses such a phrase as ‘aggregatum perceptionum’, butthere is at least one bit of evidence that he would be prepared to countenancesuch an expression; there is a passage in Couturat where he speaks of a state as‘an aggregate of changeable . . . contemporaneous predicates’.22 Clearly, in themature metaphysics, with the exception of appetition, the only predicates orproperties of substances are perceptions.

Such a defence is ingenious, but it runs into serious difficulties. For onething, the defence cannot be maintained unrestrictedly for texts after June1704, for as we have seen, on at least one occasion Leibniz is explicit that bodiesare aggregates of substances. Moreover, it is not open to Loeb to argue thatLeibniz always has perceptions inmind when he speaks of bodies as aggregates,for he holds that up to June 1704 Leibniz does claim that bodies are in somesense aggregates of simple substances. Thus, when on 20 June 1703 Leibniz tellsDe Volder that bodies are ‘only beings by aggregation and therefore phenom-ena’ (G II 252), it is this thesis which he is advancing. Now not only doesLeibniz continue to speak of bodies as entities by aggregation after June 1704;he also repeats the claim that, precisely as aggregates, they are phenomena.Thus Leibniz answers Des Bosses’s question why the apple appears roundrather than square by saying: ‘I reply that the apple itself, since it is a beingby aggregation, is only a phenomenon’ (20 September 1712, G II 461; L 607).Loeb’s thesis, then, seems to ask us to believe that on the two occasions whenLeibniz advanced this claim, he meant two radically different things by it. Onthe first occasion, he meant that bodies are phenomena by virtue of beingaggregates of substances; on the second occasion he meant that bodies arephenomena by virtue of being aggregates of perceptions. Now if Leibniz wereequivocating in this way, we could accuse him of being disingenuous, andwithout entering into discussions of Leibniz’s sincerity, we can surely agree thata philosopher’s equivocations are not to be multiplied beyond necessity.

It seems, then, misleading to claim, as Loeb does, that the phenomenalistaccount of bodies stabilized as Leibniz’s view matured. To say this is notnecessarily to deny that Leibniz flirted with phenomenalism; as we have seen,many of his remarks are most naturally read in this way. But flirtation is onething; outright infidelity another, and there is no reason to deny that Leibnizwas really unfaithful to the aggregate thesis. Yet although this seems to be the

22 L. Couturat (ed.), Opuscules et fragments inédits de Leibniz (Paris: Alcan, 1902), p. 473.Quoted in M. Kulstad, ‘Some Difficulties in Leibniz’s Theory of Perception’, in Hooker (ed.),Leibniz, p. 72.



correct reading of the evidence, it is easy to see why Loeb should have reachedthe conclusion he did, for in crucial respects the phenomenalist position seemsthe more attractive option. Some of us may find ourselves wishing that Leibnizhad been guilty of infidelity to the aggregate thesis, even while recognizing thathe was not. The aggregate thesis involves major difficulties, and it is to theseI now turn.

I II

Leibniz’s thesis that bodies are aggregates might seem to be subject to anobvious contradiction. Taken at face value it amounts to the claim that anextended mass is identical with a group of indivisible substances. How couldthis possibly be the case? But as we have already suggested, this is no doubtan uncharitable reading. We can perhaps better capture Leibniz’s thought bysaying that a certain collection or group of monads appears to us as extendedmass. When we consider what is added by the perceiving mind, the mostprominent contribution is the unity which the table in front of me appears tohave (indeed which, qua table, it does have): ‘Such is the nature of corporealmasses; they are, so to speak, beings by aggregation, the unity of which is fromthe perceiver’ (to De Volder, undated, G II 276; AG 182). But though Leibnizdwells most on the unity, wemust not suppose that this is the only contributionmade by the perceiver: ‘And aggregates themselves are nothing but phenomena,since things other than the monads making them up are added by perceptionalone, by virtue of the very fact that they are perceived at the same time’ (to DesBosses, 29 May 1716, G II 517; AG 203). The contribution of the perceivingmind extends to everything distinctive of the phenomenon of body.Robert Adams has observed that Leibniz’s thesis that the unity of aggregates

is purely phenomenal is a special instance of his general conceptualism aboutabstract objects. According to Leibniz, universals and relations exist onlyin the mind, and the same treatment is extended to the unity of aggregates.As Adams writes:

In Leibniz’s ontology, the only things that have being in their own right areparticular ‘substances or complete Beings, endowed with a true unity, with theirdifferent successive states’ . . .Everything else, including universals and also in-cluding aggregates, ‘being nothing but phenomena, abstractions, or relations’ . . . isat best a being of reason (ens rationis) existing in themind and dependent on beingthought of.23

23 Adams, ‘Phenomenalism and Corporeal Substance’, p. 240.



But though the unity of bodies is something mental, it is not merely thoughtabout; it is an essential feature of our perception of the world. In this respectthere would seem to be a disanalogy with other entia rationis, for instance,at least some relations. The relation of fatherhood is not an object of sense-perception, though there may be perceptual similarities between the twoindividuals which are causally connected to the fatherhood relation. Wemight bring out the contrast involved in the case of unity by saying that wehave a natural tendency to perceive things rather than mere clusters offeatures. We could perhaps imagine a world in which we had no such dispos-ition to perceive unified objects. In such a world the objects of perceptionwould be feature clusters, and the unity of the cluster would be as much amatter of convention as the unity of the members of a university department.But clearly this would not be our world. The fact that Leibniz would besympathetic to such a point is suggested by one reading of his claim that theidea of substance is an innate one (NE Preface, A VI.vi; RB 51).

Leibniz’s metaphysical thesis that bodies are aggregates of monads thusraises two distinct problems. There is a problem of coherence: how can anextended mass be identified with an aggregate of indivisible, unextendedmonads? The answer to this is that such collections appear to us as extendedand unified. This answer in turn generates a second problem which is a causalone.Why is it that monads appear as bodies having the phenomenal propertiesof extension and unity? These properties could be contributed by the mindwithout thereby being objects of sense-perception; but in fact we do not merelyconceive or think of bodies as extended and unified; we perceive them as havingthese properties. And thus Leibniz’s metaphysics has to explain the fact thatthrough our senses we are acquainted with extended, unified masses.

Here it is interesting to consider Descartes’ metaphysics by way of contrast.Descartes also holds that the fact that we are endowed with sense-perception issomething which philosophy can and must explain; like Leibniz, he holds thatsense-perception is a source of only confused knowledge. Unlike Leibniz,however, he has a relatively clear account of why this is so. For Descartes themind in itself possesses only clear and distinct ideas of the properties of physicalobjects; but when the mind is immersed in or mixed up with the body, the clearand distinct ideas of the intellect become confused, and the result is the form ofknowledge we call sense perception (Meditations VI, AT VII 81; CSM II 56).If the mind could somehow be taken out of the body we should find that itwas engaged in contemplating the clear and distinct ideas of the intellect (toHyperaspistes, August 1641, AT III 424; CSMK III 208). Descartes’ account ofthe confusion involved in sense-perception thus crucially involves his interac-tionist dualism: extended substance acts on thinking substance in such a way asto produce the confused form of knowledge which is sense-perception.

Consider now the position of Leibniz. Leibniz has abandoned the thesis ofmind–body interaction, so it is not open to him to explain sense-perception in



terms of the effect of body on mind. But Leibniz has abandoned not onlyinteractionism but the whole dualist framework, and this reminds us that hehas more to explain than Descartes. For Descartes, sense-perception maymislead us about many things; in particular, it is responsible for the falsebelief that bodies in themselves really possess secondary qualities in a non-relational and categorical manner. But it does not mislead us when it informsus that there really are bodies, occupying space, which exist independently ofany perceiver; this is not to say that sense-perception can provide us withknowledge of this truth. For Leibniz, by contrast, the realm of the phenomenalis much more extensive: it embraces not just secondary qualities but primaryqualities as well. Thus, by abandoning dualism, Leibniz has ensured that hehas more to explain than Descartes; by abandoning interactionism he hasdeprived himself of a relatively clear account of how such confused awareness(misperception) comes about. Leibniz thus has to perform a bigger task thanDescartes with seemingly less adequate tools. What takes the place of mind–body interaction is the obscure notion of materia prima—the stuff-factor inthe monad which is responsible for confused perception (to De Volder, 20June 1703, G II 252; L 530).According to the aggregate thesis, sense-perception involves a more radical

misrepresentation of the world than anything Descartes envisaged; the task ofexplaining such misperception is assigned solely to the obscure concept ofmateria prima. How far such a picture can be made intelligible may bedisputed, but we can, I think, agree that, ceteris paribus, we should prefer analternative account which did not put such a heavy burden on the notion ofmateria prima. This is precisely the attraction of the phenomenalist thesis. Foron this account we do not have to say that when I look at the table I amconfusedly representing a colony of monads, and mymateria prima is causingme to go wrong in this way. There is, as it were, nothing behind my perceptionof the table. This seems an obvious advantage, but it might be thought that wehave now gone too far in the opposite direction. For Leibniz would still want tohold that my perception of the table is confused, and unless he makes changesin his metaphysics, he will hold that such confusion results from materiaprima.Wemay not like the concept, but if we are to show how a phenomenal-ist account of bodies is compatible with Leibniz’s deep metaphysics, then wemust find a role for it. But, in fact, there is nothing in the phenomenalist thesiswhich requires us to deny that sense-perception is confused knowledge. Forthe phenomenalist thesis accommodates the confusion requirement in orderto explain how each substance perceives the whole universe according to itspoint of view. I perceive the whole table, but according to my viewpointI perceive parts of it more clearly than others. It may seem that this is tointerpret ‘point of view’ in spatial terms, but this is only superficially so; inreality my spatial viewpoint is a logical construction out of the distribution ofclarity and distinctness over my perceptual states.



IV

There is a second cumbersome feature of the aggregate account which thephenomenalist thesis manages to avoid. According to the aggregate thesis, myperception of the table is a confused representation of a collection of monads.But Leibniz says many things which suggest that all I directly perceive areprivate objects. AsMcRae says, this thesis is strongly suggested by the followingpassage:24

I judge without proof, from a simple perception or experience, that those thingsexist of which I am conscious within me. There are, first,myself, who am thinkinga variety of things, and then, the varied phenomena or appearances which existwithin my mind. Since both of these, namely, are perceived immediately by themind without intervention of anything else, they can be accepted without ques-tion, and it is as exactly as certain that there exists in my mind the appearance of agolden mountain or of a centaur when I dream of these, as it is that I who amdreaming exist, for both are included in the one fact that it is certain that acentaur appears to me.

(G VII 319; L 363).

It seems, then, that what happens when I perceive a table is that I directly orimmediately perceive only the varied phenomena or appearances which existin my mind. Now an aggregate of monads certainly does not exist in my mind.It follows, then, that my perception of the real table is not only confused; it isalso indirect, for it is mediated by my private mental objects. In other words,no monad ever perceives another monad directly. The aggregate thesis thusinvolves a commitment to an idealist version of the veil-of-perception doc-trine. To be sure, this is not the veil of perception which is familiar to us fromstandard accounts of Locke and which Berkeley is supposed to have attacked.But it preserves an essential feature of that doctrine in that it postulates theexistence of unknowables. And such a doctrine will be widely regarded asphilosophically unsatisfactory. The phenomenalist thesis, by contrast, tearsdown the veil of perception; it shows how the notion of an objective fact can beexplicated in terms of objects of conscious and unconscious experience.

Since the aggregate thesis seems subject to such difficulties, why did notLeibniz opt for outright phenomenalism? Unfortunately he does not tell us, soany answer must be somewhat speculative. Now it might be suggested that theexplanation is to be found in his abiding concern with theodicy, a concernwhich he shares with Descartes. In theMeditations Descartes argues that Godwould be a deceiver if there were no independently existing physical world,and one might suppose that Leibniz feels the force of the Cartesian argument.

24 R. McRae, ‘As Though Only God and It Existed in the World’, in Hooker (ed.), Leibniz,pp. 79–80.



Even for a theistic philosopher, however, this argument is not compelling;certainly it did not impress the theologically-minded Berkeley. But Berkeleyhas his own special way of blocking the argument: for him, the independentexistence of physical objects is self-contradictory, and God is not responsiblefor our errors if we choose to believe contradictions. Now Leibniz does nothave Berkeley’s response at his disposal, but he agrees with Berkeley in hisrejection of the Cartesian argument:

The argument by which Descartes tries to prove that material things exist is weak;it would have been better not to try. . . .To [Descartes’ argument] we can reply thata sensation may come from some other being than God, who permits other evilsfor certain important reasons and who can also permit us to be deceived withouthaving himself the character of a deceiver, especially since this involves no injury,since it would rather be disadvantageous for us to be undeceived. Besides, there is afurther fallacy in that the argument neglects another possibility—that while oursensations may indeed be from God or from someone else, the judgment (as towhether the cause of the sensation lies in a real object outside of us), and hence thedeception itself, may originate in us. A similar thing happens when colours andother things of this sort are held to be real objects

(G IV 366–7; L 391–2)

For Leibniz, the benevolence of God does not entail the mind-independence ofphysical objects.It is not, then, the threat of a deceiving God which prevents Leibniz from

adopting phenomenalism. But it would be premature to conclude that theo-logical considerations are altogether irrelevant; rather, their relevance may besimply less direct than we might suppose, for we need to invoke physics aswell. Recall that throughout the mature period of his philosophy Leibniz seeksto underpin his metaphysics by arguments from physics: he claims that thephysical force of bodies can only be explained by postulating immaterial souls.According to Leibniz, active force or vis viva derives from the primitive force orappetition of monads. There is much that is obscure about this doctrine, andcommentators have frequently taken it to be unsatisfactory. Thus MargaretWilson remarks that Leibniz never fills in any of the steps that might take onefrom ‘forces’ in physics to ‘souls’ in metaphysics.25 But despite the obscurity ofLeibniz’s doctrine, it seems clear that, for any body, there is some group ofmonads to which it stands in a privileged relationship. It is impossible to seehow physical force could derive from the primitive force of monads if bodieswere simply harmonized sets of perceptions. As Loeb points out, within thephenomenalist framework one cannot argue from the existence of physicalforce to the proliferation of monads.26 One can, I think, go further, and say

25 M. Wilson, ‘Leibniz’s Dynamics and Contingency in Nature’, in Woolhouse (ed.), Leibniz’sMetaphysics and Philosophy of Science, p. 136.

26 Loeb, From Descartes to Hume, p. 307.



that a phenomenalist interpretation of bodies is not consistent with the claimthat physical force derives from the primitive force of monads.

We are now in a position to suggest why Leibniz never did more than flirtwith phenomenalism. At the heart of his philosophy is the idea of synthesizingthe most recent advances in physics with an essentially traditional metaphys-ics. Such a metaphysics would find a central place for the spiritual entitiesrequired by orthodox theology and in danger of being banished by thematerialist philosophy of the age. But despite its obvious attractions, phenom-enalism could not be integrated with the reconciling project. Leibniz couldonly espouse phenomenalism at the price of abandoning his most cherishedphilosophical ambitions. Such a price, I suggest, appeared to Leibniz as just toohigh. So Leibniz did not take the path that Berkeley took. The project ofsynthesizing physics and metaphysics meant much more to Leibniz than it didto Berkeley.



13

Lockean Abstractionism VersusCartesian Nativism

Progress in the history of philosophy can sometimes best be made by changingthe topic of conversation. In the case of Locke’s theory of abstract ideas such achange seems both timely and desirable. Here, as elsewhere, Berkeley has beenallowed for too long to dominate the course of the conversation. Discussion ofLocke’s doctrine has been almost entirely concerned with the issue whetherBerkeley’s famous criticisms of the doctrine are justified. By contrast, philoso-phers have shown little interest in the question of the role that the doctrine ofabstract ideas is supposed to play in the project of the Essay as a whole. Manyscholars would agree, if pressed, that the doctrine is intended to serve as areplacement for Descartes’ equally famous theory of innate ideas, but there hasbeen scant curiosity about how far this is the case. In this essay I shall argue that,with certain important and principled exceptions, the theory of abstract ideas isa rather systematic replacement for the Cartesian doctrine. The underlyingmotivation of the essay is to emphasize that systematicity is a mark of Locke’swhole critique of Descartes’ theory of knowledge and philosophy of mind.To say that Lockean abstractionism does duty for Cartesian nativism is not

of course to deny that it plays other roles as well. Indeed, as Michael Ayersreminds us, Locke appeals to his theory of abstract ideas to perform tasks whichhave little or nothing to do with the refutation of Cartesian nativism.1 In BookIII of the Essay, for instance, the doctrine of abstract ideas occupies a prominentposition in Locke’s polemic against the Scholastic theory of essences. Againstthe Scholastic teachings, Locke denies that one and the same essence does thejob of explanation and classification: whereas the real essence explains the

1 M. Ayers, Locke: Epistemology and Ontology (London: Routledge, 1991), vol. 1, pp. 243–4.Versions of this essay were presented at a meeting of the Cartesian Circle at the University ofCalifornia, Irvine in August 2004 and at a conference at California State University, Long Beachin February 2005. I am grateful to members of the audiences on those occasions and in particularto Kenneth Brown, the late Paul Hoffman, Lawrence Nolan, Alan Nelson, and Nicholas Whitefor their helpful comments. I am also grateful to David Owen and Gideon Yaffe for their valuableeditorial suggestions.


phenomenal properties of bodies, the nominal essence, which is an abstractidea, classifies substances into sorts or species. Moreover, even when Descartesis clearly the target of attack it may be doubted how far Locke’s theory ofabstract ideas andDescartes’ theory of innate ideas play comparable roles in thetwo philosophies. Indeed, as we shall see in Sections II and III, the ‘SystematicReplacement Thesis’, as we may call it, seems open to objections from two verydifferent, even opposing, angles. But first we must examine some of thestrongest evidence for the Systematic Replacement Thesis.

I

In a striking passage in Book IV of the Essay Locke writes: ‘All generalKnowledge lies only in our own Thoughts, and consists barely in the contem-plation of our own abstract Ideas’ (Essay IV.vi.13). Such a sweeping claim leavesthe reader in no doubt about the central role played by abstract ideas in Locke’stheory of knowledge. Indeed, to the initiated reader such a passage even has theair of a manifesto: Locke is implicitly proclaiming that he intends to offer anabstractionist account of scientia or universal necessary knowledge to replaceDescartes’ mistaken nativist account. For both philosophers, of course, geom-etry is the very paradigm of scientia or universal necessary knowledge, and it issurely no accident that the two philosophers turn to geometry for perhaps theirmost prominent examples of innate and abstract ideas respectively. For Des-cartes, when I know a geometrical theorem concerning a triangle, my will iscompelled to assent to the proposition by the clear and distinct idea of a trianglethat I bring forth from the treasure house of my mind. For Locke, by contrast,I attend to an abstract idea—that is, a product of a mental process of abstrac-tion—and perceive its relations of agreement or disagreement with other ideas.

One fascinating case where Locke seeks to offer an abstractionist and anti-nativist account of scientia is in his discussion of eternal truths. The interest andimportance of this discussion have been recognized by Michael Ayers whowrites: ‘The theory of abstraction in the Essay was above all an attempt toexplain the universality, a priori cognizability, and timelessness of the eternaltruths without impugning the sensory character of what is before themind, andwithout departing from the general principles of intuitionism.’2 Otherwise thediscussion has received little attention from philosophers, perhaps because it isoddly misplaced at the end of the chapter on the knowledge of the existence ofbodies. Even Ayers, who is sensitive to the importance of the discussion, doeslittle to analyse Locke’s argument in detail.

2 Ayers, Locke, vol. 1, p. 233.



Locke’s target is clearly Descartes’ thesis that the eternal truths ‘are allinborn in our minds’ which is advanced in a famous letter to Mersenne (15April 1630, AT I 145; CSMK III 23).3 But it is important to note that thoughDescartes is the target, in one key respect Locke and Descartes are on the sameside; that is, they are united in their opposition to any form of Platonism aboutthe eternal truths.4 Neither Descartes nor Locke subscribes to the thesis thatthere is a ‘third realm’ of eternal truths, whether this is located outside God orsomehow inside him, as in the case of Malebranche. Moreover, Locke andDescartes are agreed in rejecting a close cousin arguably embraced by Leibniz:that is, they reject the thesis that the divine intellect is the realm of the eternaltruths, construed in psychological terms, as God’s propositional thoughts.5

Descartes indeed has distinctive reasons of his own for rejecting such adoctrine: his rigorous insistence on the absolute simplicity of God excludesany recognition of a divine intellect distinct from his will. Locke’s case againstthe Leibnizian position is less clear, or at least less explicit. But in any case,whatever their reasons for rejecting such views, Locke and Descartes areagreed: ‘the eternal truths have no existence outside our thought’ (Principlesof Philosophy I.48, AT VIIIA 22; CSM I 208). Thus the debate between Lockeand Descartes is entirely within the ranks of the anti-Platonists who regardideas, and the truths resulting from them, as psychological entities.As Locke sees it, any satisfactory account of the eternal truthsmust be able to

meet two challenges. The more straightforward of the two challenges is toexplain how the eternal truths are known: Descartes, of course, answers thisquestion by saying that we attend to items that have been implanted in ourmind by a benevolent God. Locke, by contrast, insists that we know them byattending to abstract ideas of our own creation and perceiving the relationsamong them. Not surprisingly, in view of his Cartesian target, Locke’s discus-sion is tailored to the case of dispositional, or in his terms, ‘habitual’ knowledge.

But wheresoever we can suppose such a creature as Man is, endowed with suchfaculties, and thereby furnished with such Ideas, as we have, we must conclude, hemust needs, when he applies his thoughts to the consideration of his Ideas, knowthe truth of certain Propositions, that will arise from the Agreement or Disagree-ment, which he will perceive among his own Ideas.

(Essay IV.xi.14)

3 Locke could have known of this letter since it was included in Clerselier’s edition ofDescartes’ correspondence. The letter is most famous for the claim that the eternal truths‘have been laid down by God and depend on him entirely no less than the rest of his creatures’.

4 The issue of Descartes’ opposition to Platonism is controversial. The case that Descartes isnot a Platonist is convincingly made by L. Nolan, ‘The Ontological Status of Cartesian Natures’,Pacific Philosophical Quarterly 78 (1997), 169–94, and by V. Chappell, ‘Descartes’s Ontology’,Topoi 16 (1997), 111–27.

5 In response to Locke’s discussion of the eternal truths Leibniz observes that the ultimatefoundation of truth is ‘that Supreme and Universal Mind who cannot fail to exist and whoseunderstanding is indeed the domain of eternal truths’ (Leibniz, NE IV.xi.14, A VI.vi; RB 447).


Lockean Abstractionism Versus Cartesian Nativism 201

It seems that Locke’s claim here could be naturally unpacked in terms of asubjunctive conditional: for Locke, to say that I habitually know an eternal truthp, is to say that if I were to attend to p, I would perceive the truth of the propositionresulting from the agreement or disagreement of the constitutive abstract ideas.

The more difficult, and more fundamental challenge which Locke faces is togive an account of the eternity of the eternal truths; by virtue of what are theeternal truths eternal? In two very similar passages Locke indicates that he isdebarred from advancing either of two proposed solutions to the problem:

Many of these [general certain propositions] are called aeternae veritates, and all ofthem indeed are so; not from being written all or any of them in the Minds of allMen, or that they were any of them Propositions in anyone’s Mind, till he, havinggot the abstract Ideas, joyn’d or separated them by affirmation or negation.

Such Propositions are therefore called Eternal Truths, not because they areEternal Propositions actually formed, and antecedent to the Understanding, thatat any time makes them; nor because they are imprinted on the Mind from anypatterns, that are any where of them out of the Mind, and existed before.

(Essay IV.xi.14)

Locke is thus drawing the reader’s attention to the fact that he is not in aposition to advance either a Platonist or a Cartesian nativist account. That is, hecannot explicate the eternity of the eternal truths in terms of their eternalexistence outside the human mind; such a solution is debarred to Lockewhether eternity is construed in strictly Platonist fashion in terms of timeless-ness and necessity, or, as Locke seems to envisage, in terms of sempiternalexistence in the mind of God. Nor, of course, is he able to advance a Cartesianaccount according to which the eternity of the eternal truths is analysed innativist terms. Just how, on Locke’s view, the nativist account is supposed to gois less clear (if the eternity is not simply parasitic on the ‘patterns’).6 Theunderlying idea seems to be that on the Cartesian nativist account there is notime in its history at which a human mind is not in possession of the eternaltruths. On the assumption that minds are immortal, any mind, once on thescene, will guarantee the unceasing existence of the eternal truths. It is naturalto object that such an account does not yield a doctrine of eternity, evenunderstood as sempiternity, if there is some time when no human mind is inexistence. To fill this gap, more controversial assumptions—for example, aboutthe pre-existence of minds—would need to be made. But of course it would notbe fair to criticize Locke for leaving the details of the nativist analysis obscure.7

6 Of course, a nativist theory which holds that God inscribes innate ideas in accordance withpatterns or archetypes in the mind would not be strictly Cartesian; for Descartes there are nosuch archetypes.

7 Cf. Chappell, ‘Descartes’s Ontology’, 126–7, for an illuminating account of Descartes’difficulties in giving an account of the eternity of eternal truths. Chappell concludes that theobjects and truths of mathematics are not, for Descartes, strictly eternal.



Whether Cartesian nativism can give a coherent account of the eternity ofthe eternal truths is unclear, but Locke’s problem is not. The objection which heseeks to answer is that the very nature of abstract ideas debars him from givingan account of the eternity of such truths; for, unlike innate ideas, abstract ideasare acquired in the course of time: small children, for instance, are lacking inabstract ideas. We might think that Locke is not without resources to fill insome of the gaps here: he could, for instance, distinguish between minds takenindividually and minds taken collectively, and he could focus on the disposi-tional, as opposed to occurrent, sense of the phrase ‘abstract idea’. But he mustconcede that there was a time when the first human mind was lacking inabstract ideas, and thus in the eternal truths which depend on them. It seems,then, that there cannot strictly be any eternal truths.To understand Locke’s solution to the problem we must borrow interpret-

ative resources derived from Descartes: that is, we must distinguish betweenthe formal and objective reality of ideas. Locke is prepared to concede thatthere is nothing that is eternal about abstract ideas, or the truths which dependon them, when they are considered in terms of their formal reality or intrinsicfeatures: even if they are taken as dispositional items, abstract ideas come intobeing and perhaps pass away. So long as we remain at this level, then, there isno hope of solving the problem of eternity. But a more promising approach isafforded by focusing instead on the objective reality of ideas. Considered inthis respect, that is, in terms of their representational content, ideas can enterinto eternal and immutable relations, and thus generate eternal truths. Impli-citly, at least, such a position is invoked in Locke’s preferred solution to theproblem of the eternity of the eternal truths:

Such Propositions are therefore called Eternal Truths . . . because being once made,about abstract Ideas, so as to be true, they will, whenever they can be supposed to bemade again at any timepast or to come, by aMindhaving those Ideas, always actuallybe true. For Names being supposed to stand perpetually for the same Ideas; and thesame Ideas having immutably the same Habitudes one to another, Propositions,concerning any abstract Ideas, that are once true, must needs be eternal Verities.

(Essay IV.xi.14)

This passage echoes an earlier one where Locke’s immediate concern is ratherdifferent—namely, to show that we may be said strictly to know the truth of aproposition when we no longer retain the demonstration of it. But in address-ing this issue Locke does something further to explicate his notion of theeternity of eternal truths:

The immutability of the same relations between the same immutable things, isnow the Idea that shews him, that if the three Angles of a Triangle were onceequal to two right ones, they will always be equal to two right ones. And hence hecomes to be certain, that what was once true in the case is always true; what Ideasonce agreed will always agree; and consequently what he once knew to be true he



will always know to be true, as long as he can remember that he once knew it.Upon this ground it is, that particular demonstrations in Mathematicks affordgeneral Knowledge. If then the Perception that the same Ideas will eternally havethe same Habitudes and Relations be not a sufficient ground of Knowledge, therecould be no knowledge of general Propositions in Mathematicks, for no math-ematical Demonstration would be any other than particular.

(Essay IV.i.9)

It may be wondered whether in passages like these Locke is helping himself toa form of Platonism without realizing or admitting it.8 But however that maybe, the moral Locke wishes to draw is clear: there is no need to postulate eithereternal ‘patterns’ (i.e. archetypes) in the mind of God or innate dispositionsinscribed on the mind by his finger in order to give an account of the eternityof the eternal truths.

Locke’s abstractionist account of the eternal truths is directed against Cartesiannativism, but it is striking how far in this instance there is common groundbetween the two philosophers. As we have seen, Locke and Descartes are agreedin rejecting any formof Platonism, or Leibnizian close cousin of the doctrine: ideasand truths are psychological entities that have no existence outside the humanmind. But Locke further agrees with Descartes not merely in distinguishingimplicitly between the objective and formal reality of ideas, but in holding that,considered in terms of their objective reality, that is, in terms of their representa-tional content, ideas are capable of entering into logical relations with one another.Indeed, at least on this issue Locke seems bent on turning Cartesian weaponsagainst Descartes himself: Descartes has the resources for advancing an account ofthe eternity of the eternal truthswithout resorting to the hypothesis of innate ideas.

I I

The case of the eternal truths is thus powerful, if rather neglected, evidencefor the Systematic Replacement Thesis. But Descartes of course appeals to

8 In correspondence Gideon Yaffe has suggested to me a way of reading Locke which wouldcertainly have the effect of clearing him of the charge of unacknowledged Platonism. Yaffe observesthat in his discussion of eternity Locke seems to regard the idea as one which calls for an analysis interms of subjunctive conditionals (Essay II.xiv.27–31): i.e. to say that x is eternal is just to say thatwere I to count the number of times that, say, the earth revolves while x exists, my counting wouldnever stop. Eternal truths, then,may be eternal for Locke in the weak sense that if I were to continueto possess and attend to the requisite abstract ideas, I should alwaysfind the propositions in questionto be true. On this interpretation the eternity of the eternal truths is constituted not by logicalrelations among mental contents but by an unlimited capacity of the mind. This interpretation isingenious, and has the merit of making important connections between different parts of Locke’stext. However, it seems to me that in key passages such as IV.i.9 and IV.xi.14 Locke does helphimself, without analysis, to the view that the contents of abstract ideas enter into immutable, logicalrelations, and that he regards the eternity of the eternal truths as constituted by such relations.



nativism not just to give an account of the eternal truths of logic andmathematics; he also invokes it to give an account of metaphysical ideas.And here it may be doubted whether the Systematic Replacement Thesis canbe sustained; that is, it may seem that there are cases where Descartes treats acertain idea as innate which Locke does not classify as abstract. It is thisobjection which forms the topic of the present section.In I.iv of the Essay Locke attacks the nativist credentials of three grand

metaphysical ideas: the ideas of identity, God, and substance. Whether or notDescartes is the exclusive target of attack here, it is plausible to suppose that heis at least a prominent target. Certainly, no philosopher is more famous thanDescartes for maintaining that the idea of God is innate; as every studentknows, in the Third Meditation this idea is supposed to be imprinted on ourmind like the mark of a craftsman stamped on this work (Meditations III, ATVII 51; CSM II 35). And in the same meditation Descartes argues that he hasthe idea of substance in virtue of the fact that he is a substance: the idea ofsubstance seems to be innate in the rather minimal sense that it is the productof non-sensory reflection on the mind’s own nature.9 Descartes’ commitmentto the nativist credentials of the idea of identity is less explicit, but is nonethe-less plausible. In any case, what is at issue here is not somuchCartesian exegesisas to how Locke may reasonably be supposed to have read his predecessor.The ideas of identity, God, and substance are not innate for Locke. But are

all, or any of them, abstract ideas? It must initially be conceded that in the caseof the first two ideas the answer seems to be ‘no’. There are indeed features ofLocke’s positive theory of ideas in Book II of the Essay which prevent himfrom claiming that either the idea of identity or the idea of God is a product ofabstraction. The idea of identity is of course an idea of relation; and accordingto the taxonomy that Locke outlines in II.xii, ideas of relation and ideas ofabstraction seem to be mutually exclusive classes.10 Certainly the two kinds ofideas are said to be formed by very different acts whereby the mind exercisesits power over simple ideas. Again, the idea of God seems not to be abstract butfor a very different reason. According to Locke’s official theory, all and onlyabstract ideas are general:11 the idea of God, however, is a particular idea,which is not capable even in principle of multiple instantiation.

9 Cf. Leibniz, NE A VI.vi; RB 51. To say that the ideas are innate for Descartes is not to saythat there is no room for abstraction; indeed at Principles of Philosophy I.63, I 215 Descartesspeaks of the notion of substance as abstracted from the notions of thought and extension. Butfor Descartes, the abstraction is from innate intellectual ideas, not from the data of sensation orreflection. Cf. Ayers’s account of the role of abstraction in the Port-Royal Logic. Ayers, Locke,vol. 1, p. 243. I am grateful to Alan Nelson for discussion of this issue.

10 Some readers may doubt whether the classification of non-simple ideas in II.xii is intendedto be exclusive. If it is not so intended then the fact that the idea of identity is an idea of relationwould not preclude its being an abstract idea.

11 Cf. Chappell, ‘Locke’s Theory of Ideas’, in Chappell (ed.), The Cambridge Companion toLocke, p. 39.



It will hardly surprise seasoned readers of Locke’s Essay to learn that themost interesting and difficult of these three cases is the idea of substance. But ifthe interest and difficulty of this case are not surprising, Locke’s officialposition on the status of this idea arguably is. In at least one place in theEssay Locke is quite explicit that the idea of substance is the product ofabstraction. The claim is made not in the famous ‘Of our Complex Ideas ofSubstances’ but in one of his canonical statements of the theory of abstractideas. In III.iii.9 Locke explains how high are the levels of abstraction to whichwe can rise by simply leaving out or eliminating more and more detail:

Leave out of the Idea ofAnimal, Sense and spontaneousMotion, and the remainingcomplex Idea, made up of the remaining simple ones of Body, Life, and Nourish-ment, becomes a more general one, under the more comprehensive term, Vivens.And not to dwell longer upon this particular, so evident in itself, by the same waythe Mind proceeds to Body, Substance, and at last to Being, Thing, and suchuniversal terms, which stand for any of our Ideas whatsoever.

(Essay III.iii.9)

In controversy with Stillingfleet, Locke again underlines the point. Stillingfleetwas understandably puzzled about the status of the idea of substance, butLocke assures him it is an abstract idea:

I beg leave to remind your Lordship, that I say in more places than one, andparticularly those above quoted where ex professo I treat of abstraction andgeneral ideas, that they are all made by abstracting, and therefore could not beunderstood to mean that that of substance was made any other way.

(LW IV 16)

Locke goes on to explain with engaging candour that slips of the pen and thelike may have misled readers as to his true position.

As readers of Locke we may be inclined to forgive the occasional slip of thepen, but we may still wonder whether he can coherently claim that the idea ofsubstance is an abstract one. Indeed, a number of problems are suggested by areview of Locke’s important discussions of the idea of substance which aredispersed through the Essay. In the first place, consider Locke’s claims aboutthe idea of substance in the very passage where he attacks its nativist creden-tials: the idea of substance, we are told, is one ‘which we neither have, nor canhave, by Sensation or Reflection’ (Essay I.iv.18). But if, as Locke undoubtedlyholds, all ideas are given in, or derive from, sensation or reflection, then surelyhe should conclude that we have no idea of substance at all; and if that is thecase, we have no abstract idea of substance. Or to run a rather different versionof the argument, if all abstract ideas are derived from sensation or reflection,and the idea of substance cannot be derived from either of these sources, thenthere is no abstract idea of substance.

One possible solution to this problem is ready to hand. In the passage whichtroubles us Locke does not mean to commit himself to the strong thesis that



the idea of substance is not ultimately derived from sensation or reflection; allhe means to assert is the weaker thesis that the idea of substance is notstraightforwardly given to us by one of these channels; that is, it is not asimple idea. Such an interpretation is indeed confirmed by a passage incorrespondence with Stillingfleet:

I never said that ‘the general idea of substance comes in by sensation and reflec-tion’ or that it is a simple idea of sensation or reflection, though it be ultimatelyfounded on them.

(LW IV 16)

This interpretation of Locke has the merit of giving him a genuine target:Descartes (and Leibniz after him) can be read as holding that the idea ofsubstance is straightforwardly given in reflection on the mind’s own nature,and thus in a rather minimal sense, innate.This interpretation certainly solves the problem of consistency in a way that

receives support fromwhat Locke tells Stillingfleet. But arguably it does less thanjustice to the full anti-Cartesian force of the passage. For Locke’s point is not somuch that the idea of substance is not straightforwardly given in sensation orreflection; it is rather that the Cartesians are wrong in supposing that we have aclear idea of substance, or one which is, as Locke puts it, ‘distinct and positive’:

We have no such clear Idea at all, and therefore signify nothing by the wordSubstance, but only an uncertain supposition of we know not what; (i.e. ofsomething whereof we have no particular distinct positive) Idea, which we taketo be the substratum, or support, of those Ideas we do know.

(Essay I.iv.18)

Such an emphasis is of course in line with Locke’s famous insistence, later inthe Essay, that our idea of substance in general is obscure and relative: it is theidea of whatever it is that supports accidents. But if our idea of substance isobscure and relative, we seem to have a new problem on our hands. For to saythat our idea of substance is relative is clearly to say that it is an idea ofrelation, and as we have seen with regard to identity, Locke seems committedto the thesis that ideas of relation and abstract ideas are mutually exclusiveclasses. Thus, if the idea of substance is an idea of relation, it cannot be anabstract idea. Or to put the objection another way, Locke seems committed toholding that the idea of substance both is and is not an abstract idea.An obvious strategy for reconciling Locke’s various claims lies in drawing

some distinctions: we might try to say, then, that the idea of substance whichis relational, or obscure and relative, is not the idea of substance which isabstract. Such a strategy is suggested by John Mackie. Mackie’s concern incontext is to explain with some care the rather complicated process by whichthe idea of substance is formed, but he also helps us with our problem. Mackieidentifies four stages in the process:



First, we notice, say, the collection of instantiated cat-features going aroundtogether, and we frame what we might call a purely phenomenal idea of thiscat: this is a ‘complication of many simple ideas together.’ Secondly, we supposean unknown central core to be what those features subsist in and result from: wenow have the idea of this particular substance, that is, this concrete existing thing,this cat: this is the combination of the phenomenal idea with the idea of anunknown core. Thirdly, from this and many like cases we abstract the generalnotion of the unknown central core of a thing, which is the idea of pure substancein general. Fourthly, from the particular phenomenal ideas of this cat, that cat, theother cat, and so on, we abstract a general idea of a collection of general cat-features, combine this with the idea of pure substance in general, and so get thegeneral idea of a particular sort of substance, namely a cat.12

An interpretation such as this, which focuses on the stages in the geneticprocess, has obvious advantages. In the first place, it satisfies our chief desider-atum for an interpretation: it clearly distinguishes between two ideas of sub-stance, or substratum, and accords the status of abstract idea to only one ofthem.Moreover, it offers a principled basis for drawing this distinction; it is onlywhen we reach the third stage in the process—that is, when we reflect on manycases—that we are in a position to form the abstract idea of substance in general.

The interpretation is attractive, but it is also open to objection. One mightwonder, for instance, whether the four stages are as sharply delineated inLocke’s text as Mackie suggests, but this is a peripheral issue. A more seriousobjection is that while it gives us good reason to suppose that only one of theideas is abstract, it gives us less reason to believe that only one of them isrelational. For the idea of substance in general which we form at stage three isstill, like the idea at the second stage, the idea of an unknown central core: ifthe idea of this core at the second stage is relational, it seems that the idea atthe third stage must be as well. We may of course deny that the general idea ofsubstance is relational, but then we must also deny that the earlier particularidea is relational, and this is implausible; for it is surely the particular idea ofthat which supports accidents. Moreover, the idea of substance in generalwhich we form at stage three is still parasitic on a process that involves anelement of supposition; at the second stage we suppose some substratumwherein the simple ideas subsist (Essay II.xxiii.1). Elsewhere (Essay II.xii.6),Locke even writes of the very idea of substance as supposed. But once anelement of supposition is introduced into the process, it seems that the purityof the abstractionist account is fatally compromised.

In fact, insofar as Locke has a considered solution to this problem it seemsnot to follow the lines of Mackie’s suggestive account: it turns not on distin-guishing various stages in a genetic process but rather on recognizing differentelements or components in a single complex idea. In reply to Stillingfleet’s

12 J.L. Mackie, Problems from Locke (Oxford: Clarendon Press, 1976), p. 74.



probing Locke explains that the general idea of substance ‘is a complex ideamade up of the general idea of something, or being, with the relation of asupport to accidents’ (LW IV 19). Sketchy as it is, this suggests Locke’ssolution to our problem. The key point in Locke’s account is that the idea ofsubstance is a complex idea that has both a general abstract idea and an idea ofrelation as its components. Strictly speaking, then, the idea of substance that isidentified as an abstract idea at III.iii.9 is not the complete idea of substance; itis only an element of that idea which needs to be supplemented by the relativeidea of support of accidents.It is difficult to avoid the conclusion that there is a tension in Locke’s

discussion of this topic arising from his having two logically distinct targetsin his sights. Consider the fact that, according to the Cartesian account thatLocke opposes, the idea of substance is not only innate; it is also clear anddistinct. In response to the former thesis Locke argues that the idea of substanceis abstract; in response to the latter thesis Locke argues, more famously, that theidea of substance is obscure and confused. But in elaborating and defending thesecond anti-Cartesian thesis Locke is led to insist on the relational nature of theidea, and in view of his taxonomy, this generates the problem of how one andthe same idea can be both relational and abstract. Thus Locke sometimessuggests that the idea of substance is abstract tout court, while at other timesrecognizing, more carefully perhaps, that it is only a component of the com-plete complex idea that is abstract. Nonetheless, whatever the tensions inLocke’s account, the central point remains: officially at least, Locke is preparedto classify the idea of substance among the abstract ideas.

I II

The Systematic Replacement Thesis, as I have called it, must also face anobjection from an opposite quarter: Locke invokes his theory of abstract ideasto perform roles which are not, and could not be supposed to be, played by thedoctrine of innate ideas in Descartes’ philosophy. As we have seen, no onedoubts that Locke appeals to abstract ideas for philosophical purposes whichhave little or nothing to do with the refutation of Descartes and the Cartesians;the doctrine of abstract ideas is central to the anti-Scholastic theory of classifi-cation which dominates Book III of the Essay. The issue before us here is ratherwhether, when Descartes is clearly in Locke’s sights, abstraction is invoked toplay a role that is played by some other doctrine in the philosophy of Descartes.One area of contention between the two philosophers where this may

seem to be the case is the debate over the status of animals. On this issue,Locke writes with something approaching dogmatism about the role played byabstraction:



This, I think, I may be positive in, That the power of Abstracting is not at all in[beasts]; and that the having of general Ideas, is that which puts a perfectdistinction between Man and Brutes; and is an excellency which the Facultiesof Brutes do by no means attain to.

(Essay II.xi.10)

Locke proceeds to defend this thesis about the distinguishing nature ofabstraction by means of an argument from language which strikingly recallsthe Descartes of the Discourse on Method (AT VI 57; CSM I 140):

For it is evident, we observe no foot-steps in [beasts], of making use of generalsigns for universal Ideas; from which we have reason to imagine, that they havenot the faculty of abstracting, or making general Ideas, since they have no use ofWords, or any other general Signs.Nor can it be imputed to their want of fit Organs, to frame articulate Sounds,

that they have no use or knowledge of general Words; since many of them wefind, can fashion such Sounds, and pronounce Words distinctly enough, butnever with any such application.

(Essay II.xi.10–11)

Here it is not only the appeal to language but also the very form of the argumentwhich, almost teasingly, is modelled on Descartes. If animals had the power ofabstraction, then since they have vocal organs of the appropriate type, theywould use language. But animals have no use of language as opposed to alimited repertoire of signals. Therefore, animals have no power of abstraction.

Locke, then, deploys an argument of Cartesian inspiration to defend theanti-Cartesian thesis that the power of abstraction is the characteristic thatdistinguishes human beings from the beasts. But it is natural to object thatthough the form of argument is Cartesian, the conclusion of Locke’s argumentis anti-Cartesian in a way quite different from what the Systematic Replace-ment Thesis would lead us to expect. If that thesis were correct, then Des-cartes’ position would be that human beings are distinguished from animals bytheir possession of innate ideas. But in fact, it may be objected, Descartes iscommitted to a much stronger thesis than that. According to Descartes, whatdistinguishes human beings from beasts is not a certain kind of mental poweror a certain kind of ideas; it is rather mentality or consciousness in general.Indeed, in the passage under discussion, Locke alludes to the strength ofDescartes’ claim when he reminds the reader that there are those who holdanimals to be ‘bare machines’.The debate between Locke and Descartes over the status of animals may

thus seem to be strong evidence against the Systematic Replacement Thesis.But in fact the issue is not as straightforward as it may appear. Consider, forinstance, how in the Comments on a Certain Broadsheet Descartes defends hiscommitment to the doctrine of innate ideas against his renegade disciple,Regius:



I have never written or taken the view that the mind requires innate ideas whichare something distinct from its own faculty of thinking. I did, however, observethat there were certain thoughts within me which neither came to me fromexternal objects, nor were determined by my will, but which came solely fromthe power of thinking within me, so I applied the term ‘innate’ to the ideas ornotions which are the forms of these thoughts in order to distinguish them fromothers which I called ‘adventitious’ or ‘made up’.

(AT VIIIB 357–8; CSM I 303–4)

Here, then, Descartes offers what appears to be a strongly reductionist accountof innate ideas as nothing over and above the faculty of thinking. So on thisaccount to say that human beings, for Descartes, are distinguished from thebeasts by a faculty of thinking is equivalent to saying that they are distin-guished by the possession of innate ideas. In this instance, then, the SystematicReplacement Thesis appears to be vindicated; innate ideas play a role inDescartes’ philosophy which is played by abstract ideas in Locke: they distin-guish human beings from the lower animals.Such a defence of the Systematic Replacement Thesis in this instance may

appear to go too fast. It is natural to object that the account ignores a keydistinction in Descartes between two senses of ‘faculty of thinking’. WhenDescartes says that innate ideas reduce to the faculty of thinking, the phrasemust be understood in a narrow sense; in this sense the faculty of thinking isequivalent to the pure intellect. By contrast, when Descartes says that humanbeings are distinguished from beasts by the faculty of thinking, it is a broadsense of the phrase that is at issue; in this sense it is equivalent to the power ofhaving consciousness in general. Thus it is misleading to suggest that theSystematic Replacement Thesis is vindicated in the case of the debate overanimals, for such a suggestion simply equivocates between two senses of theterm ‘faculty of thinking’.Once again it is helpful to remind ourselves of the central issue here. The

question is not so much the correct exegesis of Descartes; it is rather how Lockemay be supposed to have understood the thought of his predecessor. It would notbe surprising if Locke failed to recognize that Descartes works with a distinctionbetween two senses of the phrase ‘faculty of thinking’. Moreover, even if such adistinction is recognized, one thing is surely uncontroversial: for Descartes,‘living creature endowed with a faculty of thinking (in the narrow sense)’ is atleast extensionally equivalent to ‘living creature endowed with a faculty ofthinking (in the broad sense)’. There are no cases for Descartes of living creaturesthat have mentality or consciousness but lack a faculty of pure intellect.13

But it is also possible to mount a more ambitious reply to the objection byclaiming that it rests on a mistake. It is true that Descartes recognizes both a

13 It is worth noting, that for Descartes, angels would seem to have a faculty of pure intellectbut no sensation, sense perception, or imagination.



broad and a narrow sense of the term ‘thought’ when what is at issue isepisodic or occurrent thinking. In the broad sense ‘thought’ covers not onlyintellectual items, but also sensations, sense perceptions, and acts of theimagination. But to say this is not to say that Descartes similarly recognizestwo senses of the term ‘faculty of thinking’. It is possible, I think, to say that forDescartes talk of a faculty of thinking is always equivalent to talk of the pureintellect. Certainly it is one and the same faculty—the pure intellect—which isinvolved not only in mathematical and metaphysical reasoning, but in havingsensations and sense-perceptions: such confused occurrent mental states arewhat results when the faculty of thinking is acted upon in a certain way by thebody with which it is united and, as it were, intermingled.

Such an interpretation seems to be supported by the nature of Descartes’argument in theDiscourse on Method whose structure Locke reproduces in theEssay for his own very different purposes. Critics have sometimes objected thatthe argument proves at most that the beasts lack a faculty of reasoning or pureintellect: it stops short of proving that they lack mentality or consciousnessin general, and thus (on the assumption that there can be no unconsciousmentality), are simply machines or automata. Why should it not be the casethat while beasts have no ability to reason they still feel hunger and pain, just ascommon sense supposes they do? But this objection may overlook the fact thatwithin the Cartesian system such a case cannot arise: for Descartes, reason orpure intellect and consciousness necessarily stand and fall together. The pos-session of a faculty of thinking or pure intellect is indeed a logically necessarycondition of having any mental state whatever. Now, as we have seen, forDescartes, innate ideas simply reduce to this faculty of thinking or pureintellect. There is thus a perfectly good sense in which, for Descartes, it isinnate ideas that distinguish human beings from the beasts and thus play a rolein this area of philosophy that is played by abstract ideas in Locke’s thought.

It is natural to object that there is still a sense in which the two doctrinesplay different roles in the two philosophies. For Descartes, it is innate ideas,understood as the faculty of thinking, which draw the line between consciousand non-conscious beings; for Locke, by contrast, abstract ideas play no suchrole of demarcation. Locke is explicit that animals enjoy at least a rudimentaryform of consciousness, even though they have no abstract ideas. Locke’sinsistence on this point may well have larger ramifications for the debatebetween the two philosophers over the nature of the mental. As I have arguedelsewhere, Locke sees how he can exploit what he regards as the evident fact ofanimal consciousness as a way of undermining confidence in Cartesian sub-stantial dualism.14 Of course the further dimension of the debate between thetwo philosophers lies outside the scope of this essay; the important point for

14 N. Jolley, Locke: His Philosophical Thought (Oxford: Oxford University Press, 1999),pp. 93–5.



our purposes is that though the Systematic Replacement Thesis may need tobe qualified, it definitely does not need to be abandoned.Near the beginning of this essay I said that my underlying motivation was to

suggest that Locke is a systematic critic of Descartes. Of course the essay cannotclaim to have justified such a general thesis; it is intended rather to serve as acase study. But the same concern with systemwill, I believe, be found in Locke’sdetermined and thoroughgoing assault on Descartes’ dogmatic commitment tosubstantial dualism. I would go further and claim that systematicity is ahallmark of Locke’s philosophy in general. Such a claim may still raise eye-brows, but at least is likely to find a more favourable reception today than, say,thirty years ago. In Problems from Locke Mackie expressed the hope thatphilosophy ‘has got past the stage of trying to settle substantive issues inmetaphysics and theory of knowledge by appeals to what is alleged to be theordinary use of language’.15 In a rather similar vein I hope that commentary onLocke has got past the stage of regarding his masterpiece as a series of analyticessays on discrete problems in metaphysics and epistemology.

15 Mackie, Problems from Locke, p. 5.



14

Dull Souls and Beasts

Two Anti-Cartesian Polemics in Locke1

Everyone knows that Locke attacks Cartesian dogmatism in his philosophy ofmind. His opposition to such dogmatism is perhaps nowhere more evidentthan in his response to the distinctively Cartesian theses that the mind alwaysthinks and that animals are just machines. Locke himself draws attention tothe similarity of spirit underlying both Cartesian doctrines in a passage full ofhis characteristic irony:

They must needs have a penetrating sight, who can certainly see, that I think,when I cannot perceive it my self, and when I declare, that I do not; and yet cansee, that Dogs or Elephants do not think, when they give all the demonstration ofit imaginable, except only telling us, that they do so.

(Essay II.i.19)

Locke criticizes the two Cartesian doctrines in much the same way. Descartesoffers a question-begging argument for the thesis that the mind always thinks,while those who ‘decree’ that animals are just machines take up this opinionmerely because their hypothesis (that only immaterial beings think) requires it(Locke to Collins, 21 March 1704, CL VIII 254). In opposition to suchdogmatism Locke preaches respect for observation and experience; indeed,he appears in his famous guise of the champion of common sense againstmetaphysical speculation run wild.

There is no doubt that, at least in the Essay, Locke encourages the reader tosee him as the defender of common sense and respect for experience againstCartesian extravagance. But it would be a bad mistake to suppose that this is allthat is at issue in Locke’s polemics; to do so would be to be deceived by one ofLocke’s favourite rhetorical devices—the familiar pose of the ‘plain, blunt man’in Mark Antony’s phrase.When we turn from the Essay itself to the evidence ofthe journals and even the Stillingfleet controversy, we see that Locke was wellaware of the wider metaphysical and even theological dimensions of the issues.

1 I am grateful to Sean Greenberg for helpful comments on an earlier draft of this essay and toJan-Erik Jones for discussion of the issues.


Locke shows that his attacks on the Cartesian doctrines serve the larger purposeof criticizing the traditional view of the mind as an immaterial substance whichis thereby naturally immortal. In opposition to this picture Locke not onlyargues that the mind may not be an immaterial substance; in the journals, inparticular, he also argues, more positively, that even if themind is an immaterialsubstance, it does not follow that it is immortal in the strong sense necessary tohave any bearing on our human concerns and interests.

I

In a remarkable entry in his journals (dated 20 February 1682), Locke criticizeswhat he terms the ‘usuall physicall proofe’ of the immortality of the soul. AsLocke explains it, the argument runs: ‘Matter cannot thinke ergo the soule isimmateriall, noe thing can naturally destroy an immateriall thing ergo the souleis naturally immortal’ (ED 121). According to Locke, the basic trouble with thisargument is that it misconceives the issue of immortality; indeed, this mistakeis made by both proponents and conventional critics of the argument alike. Forwhen personal immortality is in question, what is at issue is not a state of baresubstantial existence and duration but ‘a state of sensibility’. But the argumentfrom immateriality is powerless to establish immortality in this strong sense; itcan establish at most only a form of indestructibility common to all substances,material and immaterial. According to Locke, it is ‘manifestly false’ to say thatthe soul is necessarily always thinking. In a passage that anticipates the polemicof the Essay, Locke draws out the implications of the thesis that the soul alwaysthinks for the issue of proving the soul’s immortality:

For I aske what sense or thought the soule (which is certainly then in a man) hasdureing 2 or 3 howers of sound sleepe without dreameing where by it is plainethat the soule may exist, or have duration for some time without sense orperception and if it may have for this hower it may also have the same durationwithout perception of pain or pleasure or any thing else for the next hower andsoe to eternity. Soe that to prove that immortality of the soule simply because itbeing naturally not to be destroid by anything it will have an eternall durationwhich duration may be without any perception is to prove noe other immortalityof the soule then what belongs to one of Epicurus’s attoms viz. that it perpetuallyexists but has noe sense either of happynesse or misery.

(ED 122)

Here, then, the ‘manifest falsity’ of the Cartesian doctrine that the mind alwaysthinks serves as a key premise in an argument to show that immateriality doesnot entail immortality in a morally significant sense.2

2 I borrow this helpful phrase from Michael Ayers who discusses this passage in his Locke:Epistemology and Ontology, vol. 2 (London: Routledge, 1991), p. 254.


Dull Souls and Beasts 215

Locke’s argument seems to take the form of a reductio. Suppose that theimmateriality of themind does entail immortality in amorally significant sense.On the assumption that the mind is immaterial, it follows, then, that the mindcan never be without sensibility after death, that is, without the perceptionof pleasure or pain. But as experience shows, the mind is sometimes withoutsensibility in this life. Now if the mind can sometimes be without sensibility inthis life, it can endure for ever (‘to eternity’) without it. Thus the mind both can,and cannot, survive death for ever without sensibility, or the perception ofpleasure or pain. But this is absurd. Therefore, the immateriality of the minddoes not entail immortality in a morally significant sense.

One problem posed by this argument is that one of its premises seemsstronger than is warranted.3 It does not seem correct to say that if the mindcan sometimes be without perception of pleasure or pain in this life, it canendure for ever without such perception. Such a premise seems on a par withsaying that if I can survive without food for a few hours, I can always survivewithout food.4Why should not the nature of the mind be such that it can go fora while without perception of pleasure or pain, but cannot persist very long insuch a state? Consistently with being an indestructible substance, it mustrestore itself, as it were, with bouts of perception of pleasure or pain. It seemsthat Locke might do better to fall back on the weaker claim: if the mind issometimes without sensibility in this life, it can sometimes be without it afterdeath. Now on such a formulation Locke can still generate a contradictionprovided immortality is understood as a state of uninterrupted perception ofpleasure or pain, or sensibility. But for theological purposes it might beadequate to understand immortality, more weakly, as involving post-mortemsurvival with interrupted perception of pleasure or pain.5 Imagine, for instance,that I survive for all eternity but am only occasionally roused from uncon-sciousness to experience bouts of appalling torment for my sins. If immortalitytook this form, the prospect of it could still make a big difference to humanconcerns. But if immortality is understood in this weaker sense, then Lockecannot generate the contradiction he needs. To say that immortality is a state ofinterrupted post-mortem sensibility is obviously consistent with saying that themind after death can sometimes be without perception of pleasure or pain.

3 Another problem is that the argument may seem to conflate the necessity of the conse-quence and the necessity of the consequent. In order to generate a contradiction Locke needs thesub-conclusion that the mind can never be without sensibility after death. But on Locke’sanalysis of immortality in a morally significant sense, this is equivalent to the claim that themind is necessarily immortal. But all Locke is entitled to is the premise that necessarily, if themind is immaterial, it is immortal.

4 Of course, the human body, unlike the mind on Locke’s supposition, is not an indestructiblesubstance. But it is still false to say that if I (that is, my human body) can survive for a few hourswithout food, I can survive without it for the whole course of a normal human life.

5 To say this is not to say that any theologian of note has actually held such a position.



It is perhaps a little unfair to subject a sketchy argument from the journals todetailed criticism; Locke indeed might object to details of the reconstructiongiven above. But whatever the merits of the argument, it is at least clear whatLocke is trying to do: he seeks to show that the fact that our mind is sometimeswithout any perception at all, and thus a fortiori without any perception ofpleasure or pain, has important implications for the issue of immortality. Theanti-Cartesian thesis, or strictly a corollary of it, thus appears as a premise in anargument designed to sever the connection between immateriality and immor-tality in a strong sense. Now in the journals entry Locke does little to argue foror defend the premise itself: although he considers the objection that the mindalways thinks, but sometimes forgets some of its past thinking, he dismisses itfairly brusquely. It is in the Essay itself that Locke offers detailed argumentagainst the Cartesian dogma that the mind always thinks. As we shall see, it isnot entirely clear whether Locke thinks he can show that the Cartesian thesis isactually false, as opposed to a merely unproven hypothesis.In the opening chapter of Book II of the Essay Locke adopts two different

strategies for attacking the Cartesian thesis. The first is a modest epistemologicalone: the thesis is simply unproven dogma. Since the thesis that the mind alwaysthinks is not self-evident, it must be proved, but to argue, as Descartes does, thatit must always think because its essence is thought is to beg the question (EssayII.i.10).Moreover, the thesis is not established by empirical evidence: experiencesuggests that there are gaps in consciousness, as in dreamless sleep. As Lockeengagingly puts it, in a tone that hasmisled readers, ‘I confessmy self to have oneof those dull Souls, that doth not perceive itself always to contemplate Ideas’(Essay II.i.10). Locke is aware, however, of the difficulty of arguing that the thesisis actually falsified by the empirical evidence; to the objection that I sleptdreamlessly all last night, Descartes can reply that my memory is deceiving me.It is uncontroversial that Locke seeks to show that Descartes’ argumentative

strategy is question-begging and that the empirical evidence does not establishthe thesis. What is less clear is whether Locke seeks to show in this chapter thatthe thesis is actually false. At first sight it may seem that the answer isobviously ‘yes’; it may seem that Locke seeks to expose the falsity of the thesisby means of a reductio ad absurdum argument. Consider, for instance, thewell-known thought experiment of Castor and Pollux: these individuals shareone continuously thinking soul which systematically alternates every twelvehours between the two bodies who sleep and wake by turns; while Castor isasleep the soul thinks continuously in Pollux’s body, and vice versa. The moralof the thought experiment is that of such a scenario we are forced to say thatthere are two persons occupying one soul. Now Locke later writes of the‘absurdity of two distinct Persons’ which follows from this supposition(Essay II.i.15). Thus it seems that Locke is arguing that the thesis leads to anabsurdity, if not in the strict sense of a contradiction, at least in the informalsense of a thesis that is wildly counterintuitive.



But this interpretation encounters difficulties as soon as we reflect onLocke’s discussion of personal identity with which his anti-Cartesian polemicotherwise seems so continuous. For that chapter abounds in suppositions likethat of the Castor and Pollux thought-experiment, but there the moral seemsto be, not that such suppositions are absurd, but rather that they force us torecognize the truth of the relativity of identity: items such as persons, souls,substances, and human beings all have different identity conditions. Lockeactually addresses the issue of absurdity towards the end of the chapter:

I am apt enough to think I have in treating of this Subject made some Suppos-itions that will look strange to some Readers, and possibly they are so inthemselves. But yet I think, they are such, as are pardonable in this ignorancewe are in of the Nature of that thinking thing, that is in us, and which we look onas our selves. Did we know what it was . . . we might see the Absurdity of some ofthose Suppositions I have made. But taking, as we ordinarily do now, (in the darkconcerning these Matters) the Soul of a Man, for an immaterial Substance,independent fromMatter, and indifferent alike to it all, there can from the Natureof things, be no Absurdity at all, to suppose, that the same Soul may, at differenttimes be united to different Bodies, and with them make up, for that time,one Man.

(Essay II.xxvii.27)

Although Locke does not explicitly address the Castor and Pollux kind ofscenario, he seems to be pointing a moral of general application; suppositionslike that of Castor and Pollux involve no absurdity on the current state of ourknowledge. One wonders, then, how Locke is entitled to speak of the absurdityof two distinct persons occupying a soul, as he does in his anti-Cartesianpolemic. It may seem that Locke has simply changed his mind on this issuebetween the first and the second edition of the Essay (in which the chapter onpersonal identity was added) without making the necessary editorial alter-ations to the earlier discussion.

It is possible to defend Locke’s actual claims about absurdity by saying thathe is indeed mounting a reductio argument, but one that is ad hominemagainst the Cartesians. The key point is that the argument includes thesuppressed, distinctively Cartesian premise that a person is necessarily identi-cal with a certain soul or immaterial thinking substance. But reflection onscenarios like that of Castor and Pollux forces even the Cartesians to recognizethat, according to intuitions we all share, two persons could occupy the samesoul. The Cartesian doctrine thus leads to a contradiction; the argument is astrict reductio, but one that embodies a distinctively Cartesian premise aboutthe nature of persons.6

6 See David Soles and Katherine Bradfield, ‘Some Remarks on Locke’s Use of ThoughtExperiments’, Locke Studies 1 (2001), 31–62.



This is an ingenious interpretation, but it receives little direct support fromthe text; at least in Book II, chapter i, Locke nowhere explicitly states theCartesian premise about persons necessary to generate the reductio.7 At thisstage it is tempting to suppose that for Locke the thought-experiments showsomething, but that he is not quite sure what. But perhaps we can do better thanthat. It seems more fruitful to read the point of Locke’s polemic in the light ofthe concern with immortality addressed in the journals. Such an approach isindeed encouraged by Locke’s explicit concern with the issues of pleasure andpain, happiness and misery in the published Essay. Locke’s point may well bethat even if the Cartesians are right about the nature of the soul, they fail to seethat their doctrine has no tendency to guarantee personal immortality in astrong, morally significant sense. The Cartesian doctrine cannot rule out thepossibility that our soul might survive death, but in such a way that stretches ofits consciousness might have nothing to do with us. Indeed, Locke may thinkthat the Castor and Pollux thought experiments show that it is possible that mypost-mortem soul might always be occupied by another person than me. Theconsciousness of my post-mortem soul might be as alien to me as Castor’sconsciousness is to Pollux. When personal immortality is in question, whatI want to know is whether I shall experience pleasure or pain, happiness ormisery; the fact that my soul after death may be occupied by another personwho experiences happiness or misery is irrelevant to the issue.Such an approach suggests a plausible way of regarding the polemic as a

whole. Locke’s argumentative strategy may be viewed as a constructive di-lemma. Either the mind always thinks or it does not. If the mind does alwaysthink, then this doctrine has no tendency to guarantee personal immortality. Ifthe mind does not always think, then an argument for personal immortality isblocked. So either way there is no rational assurance of personal immortality.The evidence of Locke’s journals suggests that his main interest in this area

is in showing that immateriality does not entail immortality in a morallysignificant sense. Now elsewhere in the Essay Locke shows that he is alsointerested in undermining Descartes’ dogmatic commitment to substancedualism; in particular, Locke seeks to break down at least our resistance tothe thinking-matter hypothesis. It is natural to ask whether in his polemicagainst the Cartesian thesis that the mind always thinks Locke is seeking toadvance that project.To prepare the ground for such a discussion it is helpful to clarify the nature

of Locke’s target in the polemic of Book II, chapter i. Locke’s prime target issurely the doctrine that the mind is a persisting immaterial substance whichalways thinks by virtue of its essence being thought. But it is instructive tonotice that there is another form that the Cartesian doctrine could take.

7 See, however, Essay II.xxvii.12 where Locke alludes to the Cartesian thesis that ‘’tis oneimmaterial Spirit that makes the same Person in Men’.



Consistently with its always thinking, the soul might be a temporally gappysubstance. On this hypothesis, during its existence the soul would thinkcontinuously, and think continuously by virtue of its essence, but it wouldgo in and out of existence.8 Surprisingly perhaps, Descartes not only considersthis option but indicates that he prefers it to the denial of the thesis that thesoul always thinks:

I believe that the soul is always thinking for the same reason that I believe thatlight is always shining, even though there are not always eyes looking at it, andthat heat is always warm though no one is being warmed by it, and that body, orextended substance, always has extension, and in general that whatever consti-tutes the nature of a thing always belongs to it as long as it exists. So it would beeasier for me to believe that the soul ceased to exist at the times when it issupposed to cease to think than to conceive that it existed without thought.

(Descartes to Gibieuf, 19 January 1642, AT III 478; CSMK III 203)

If Locke is targeting all versions of the ‘soul always thinks’ hypothesis, thenthis version must fall within the scope of his polemic. It is true that Locke’sarguments are not effective against this version; for instance, he cannot appealto the empirical evidence of dreamless sleep in order to criticize it. Nor doesthe thought experiment of Castor and Pollux gain any traction against thisversion of the thesis. Of course Locke could say that the hypothesis of a soulthat goes in and out of existence runs counter to the traditional notion of asubstance as something that persists uninterruptedly through time; a sub-stance, according to the Aristotelian tradition, is not only a bearer of proper-ties but a temporal persistent. It is true that Locke believes that persons aretemporally gappy entities, but then he is explicit that persons are not sub-stances. Just how Locke would criticize this further version of Descartes’ thesisis not certain, but one thing is clear: Locke never suggests that in this modifiedform the ‘soul always thinks’ thesis might be defensible.If Locke shows no sympathy for the modified version of the thesis, what

doctrine, if any, does he wish to defend? His only explicit offering on this pointis the suggestion that

the perception of Ideas [is] (as I conceive) to the Soul, what motion is to the Body,not its Essence, but one of its Operations: And therefore, though thinking besupposed never so much the proper Action of the Soul, yet is not necessary tosuppose that it should be always thinking, always in Action.

(Essay II.i.10; cf. Essay II.xix.4)

The suggestion that thought might be an operation of the soul may seemstraightforward and innocent enough, but it is in fact fraught with difficulties.The unwary reader may easily take Locke to be saying that thinking is the

8 I am grateful to Nicholas Sinigaglia for discussion of this point.



operation, but not the essence, of an immaterial substance; that is, he mightsuppose that Locke agrees with Descartes about this aspect of the ontology ofsouls, while disagreeing with his thesis that thought constitutes their essence.But this reading goes beyond anything Locke says. And reflection suggests thatit is not philosophically attractive to combine the doctrine that souls areimmaterial substances with the further thesis that thought is merely anoperation of the soul. For we would be invited to suppose that throughstretches of its history, the soul is endowed merely with bare powers, un-grounded, it seems, in any structural properties. And such a hypothesis mightwell seem to smack of barren Scholasticism.In the face of such difficulties Jonathan Bennett has argued that at least a

weak form of materialism would be harmonious with Locke’s actual claims,and indeed with the overall tone of his philosophy of mind. According toBennett, Locke’s real position may be the following:

‘While the man is sleeping, and not dreaming, there isn’t any such object as hismind or soul. The fundamental reality at that time consists in a sleeping animalwhich can, and when it receives certain stimuli will, start thinking again.’ This is along way short of the kind of materialism that finds favor with most Anglophonephilosophers today, but it is a step along the way.9

I agree with Bennett that this form of non-reductive materialism is philosoph-ically more attractive than the other options considered so far, and that Lockewould have agreed that it was; indeed, it is entirely consistent with thehypothesis, discussed by Locke in Book IV, chapter iii, that God may havesuperadded the power of thinking to matter.10 But before endorsing Bennett’saccount of Locke’s real position, we need to pay closer attention to furtherfeatures of Locke’s text. Locke does not offer much in the way of help, but whathe does offer is suggestive.For any reader attuned to Locke’s philosophy as a whole, the most striking

features of the passage are the negative claim about essence and the parallelbetween soul and body. We know that the topic of essences was one to whichLocke devoted serious and sustained attention. According to Locke, any philo-sophically worthwhile discussion of the nature of essences must distinguish

9 J. Bennett, ‘Locke’s Philosophy of Mind’, in Chappell (ed.), The Cambridge Companion toLocke (Cambridge: Cambridge University Press, 1994), p. 114.

10 ‘We have the Ideas of Matter and Thinking, but possibly shall never be able to know,whether any mere material Being thinks, or no; it being impossible for us, by the contemplationof our own Ideas, without revelation, to discover, whether Omnipotency has not given to someSystems of Matter fitly disposed, a power to perceive and think, or else joined and fixed to Matterso disposed, a thinking immaterial Substance: It being, in respect of our Notions, not much moreremote from our Comprehension to conceive, that GOD can, if he pleases, superadd to Matter aFaculty of Thinking, than that he should superadd to it another Substance, with a Faculty ofThinking’ (Essay IV.iii.6).



between the real and the nominal essence. As Locke explains in Book III, thenominal essence is an abstract, general idea constituted by that set of (observ-able) properties in terms of which we classify particulars into sorts; the realessence, by contrast, is that internal constitution of a thing on which itsobservable properties depend (Essay III.iii.15–17). Thus when Locke deniesthat thinking is the essence of the soul, it is natural to ask whether it is real ornominal essences that are at issue, or perhaps both. Consistently with thesuggestive parallel with body and motion, Locke could say that thought doesnot constitute, and is not even part of, the nominal essence of the soul; for weknow that Locke writes that the nominal essence of body can be captured bysaying that it is an extended, solid substance (i.e. without the inclusion ofmotion) (Essay III.vi.21; cf. Essay III.x.15). In places Locke seems to allow thatthe nominal essence of mind or spirit can be captured by saying that it is athing with a power of thinking (Essay II.xxiii.3). However, Locke has less tosay about the nominal essence of mind or spirit than about the nominalessence of body. Moreover, it is a complicating fact that, at least according toLocke’s official teaching, there is no right or wrong answer to questions of theform: what is the nominal essence of x?; nominal essences simply differ fromperson to person depending on their observation of co-occurrent propertiesand their decisions about which properties to include. When he denies thatthinking is the essence of the mind, Locke seems to be addressing an issuewhere there is a fact of the matter that can in principle be discovered. Thus itseems safest to say that Locke’s negative thesis should be understood as aclaim about the level of real essences: thought does not constitute the realessence of mind or soul.

If thought does not constitute the real essence of mind or soul, then whatdoes constitute it? Here we encounter Locke’s famous thesis about realessences, made most conspicuously in connection with so-called naturalkinds, that they are unknown to us: the real essence of gold, for instance, isa certain unknown constitution of physical particles. Now it is consistent withLocke’s agnosticism in this area that the real essence of the soul might turnout to be a certain structure of particles, say in the brain. But it is alsoconsistent with Locke’s agnosticism about real essences that the real essenceof the soul might be something that is neither mental (according to ourcurrent concepts) nor physical at all.11 The materialist option is thus notthe only option that is left open by Locke’s polemic against the thesis that thesoul always thinks.

11 For this highly original approach to Locke on the mind–body problem, see Han-Kyul Kim,‘Locke and the Mind-Body Problem: An Interpretation of his Agnosticism’, Philosophy 83(2008), 439–58, and ‘What Kind of Philosopher was Locke on Mind and Body?’ PacificPhilosophical Quarterly 91 (2010) 180–207.



II

We have seen that, in the Essay and elsewhere, Locke regards the beast-machinedoctrine, no less than the thesis that the mind always thinks, as a symptom ofthe same philosophical vice: both doctrines are expressions of metaphysicaldogmatism that flies in the face of common sense and pays insufficient respectto observation and experience. In a letter to Collins, Locke writes that those likeNorris who subscribe to the beast-machine doctrine, ‘seem to me to decreerather than to argue. They against all evidence of sense and reason decree Brutesto be machins onely because their hypothesis requires it and then with a likeauthority suppose . . . what they should prove, viz. that whatsoever thinks isimmaterial’ (Locke to Collins, 21 March 1704, CL VIII 254). Now Locke mayindeed share the outrage of his compatriot HenryMore and others at Descartes’doctrine of the beast-machine, but again, it would be wholly mistaken tosuppose that on this issue Locke is simply concerned to defend commonsense against Cartesian dogmatism. In the same journal entry in which hestigmatizes the thesis that the soul always thinks as manifestly false, he showshimself well aware of how issues about immortality and thinking matter areinvolved in debates over the beast-machine doctrine. In particular, as we shallsee, Locke holds that one argument for the beast-machine doctrine depends onthe false assumption that immateriality entails immortality in the strong,morally significant sense. It is in the Stillingfleet controversy rather than theEssay that Locke returns to the explicit discussion of these issues. But first wemust consider Locke’s treatment of animals in the Essay.

At first sight Locke’s discussion of the status of animals in the Essay isdisappointing. Certainly it stands in striking contrast to his polemic againstthe Cartesian thesis that the soul always thinks. Not merely does Locke fail toexplore the metaphysical and theological dimensions of the beast-machinedoctrine in the Essay; he does not engage in extended polemic against it.Indeed, although there are a number of sharp remarks at its expense, there islittle or nothing in the way of direct arguments designed to refute the doctrine;Locke takes it as simply obvious that animals have at least some mentalfaculties. Perhaps the explanation of this difference in the approaches to thetwo issues is that the beast-machine doctrine was widely regarded as dis-credited; certainly it failed to impress readers of Descartes such as HenryMore. But though Locke does not seek to refute the Cartesian dogma in theEssay, he does offer an interesting argument for a thesis about the mentalfaculties of animals; indeed, the argument draws on Descartes himself forinspiration. As we shall see, this argument bears at least indirectly on the issueof the thinking-matter hypothesis.In a passage buried deep in the chapter ‘Of Discerning’ Locke offers an

argument for the thesis that animals lack the power of abstracting. A strikingfeature of this argument is its similarity in structure to a famous argument of



Descartes’ in the Discourse on Method. The Lockean argument is so similar atpoints that it is worth quoting Descartes’ argument to bring out the similarity.Here is how Descartes argues for the thesis that animals lack reason orintelligence:

[W]e can also know the difference between man and beast. For it is quiteremarkable that there are no men so dull-witted or stupid – and this includeseven madmen – that they are incapable of arranging various words together andforming an utterance from them in order to make their thoughts understood;whereas there is no other animal, however perfect and well-endowed it may be,that can do the like. This does not happen because they lack the necessary organs,for we see that magpies and parrots can utter words as we do, and yet they cannotspeak as we do: that is, they cannot show that they are thinking what they aresaying. On the other hand, men born deaf and dumb, and thus deprived of speech-organs as much as the beast or even more so, normally invent their own signs tomake themselves understood by those who, being regularly in their company, havethe time to learn their language. This shows not merely that the beasts have lessreason than men, but that they have no reason at all.

(AT VI 57–8; CSM I 140)

Now Locke agrees with Descartes that considerations about language andvocal organs show something about animals, but he believes that they showless than Descartes thinks: what they show is simply that animals lack onemental faculty that is possessed by human beings:

This, I think, I may be positive in, That the power of Abstracting is not at all inthem; and that the having of general Ideas, is that which puts a perfect distinctionbetwixt Man and Brutes; and is an Excellency which the faculties of Brutes do byno means attain to. For it is evident, we observe no foot-steps in them, of makinguse of general signs for universal Ideas; from which we have reason to imagine,that they have not the faculty of abstracting, or making general Ideas, since theyhave no use of Words, or any other general Signs.Nor can it be imputed to their want of fit Organs, to frame articulate Sounds that

they have no use, or knowledge of generalWords; sincemany of them, we find, canfashion such Sounds, and pronounceWords distinctly enough, but never with anysuch application. And on the other side, Men, who through some defect in theOrgans, want words, yet fail not to express their universal Ideas by signs, whichserve them instead of general words, a faculty which we see Beasts come short in.And therefore I think we may suppose, That ‘tis in this, that the species of Brutesare discriminated from Man, and ‘tis that proper difference wherein they arewholly separated, and which at last widens to so vast a distance.

(Essay II.xi.10–11)

Locke’s argument can thus be reconstructed as follows:

(1) If animals have the power of abstraction, then if they have fit vocalorgans, they use general terms.

(2) Animals have fit vocal organs.



(3) Animals do not use general terms.(4) Therefore, animals lack the power of abstraction.

Now Locke has earlier claimed in the same chapter that animals have limitedpowers of comparing, compounding, and discerning their ideas. The picturethat emerges, then, is that animals have some mental faculties in common withhuman beings, while lacking one other faculty altogether.The thesis that animals lack the power or faculty of abstraction has important

implications for epistemology. It is a central tenet of Locke’s theory of knowledgethat ‘all general Knowledge lies only in our own Thoughts and consists barely inthe contemplation of our abstract Ideas’ (Essay IV.vi.13); abstract ideas areintegral to Locke’s anti-Cartesian, anti-nativist theory of scientia or universalnecessary knowledge. Thus animals have reason, but they are incapable ofscientia. But though Locke’s thesis is important for epistemology, it has no directimplications for metaphysics. Certainly, it does not entail materialism in anyform; it is consistent, for instance, with a Leibnizian ontology according towhichanimals, like human beings, have souls which are immaterial substances thoughof a less excellent kind. Nonetheless, the account of animal mentality that Lockesketches in the chapter ‘Of Discerning’ is certainly harmonious with the think-ing-matter hypothesis that Locke refuses to exclude in Book IV of the Essay: whynot suppose that differences between human and animal consciousness are to beunderstood in terms of differences in the organization ofmatter in the two cases?That Locke himself was well aware of how the thinking-matter hypothesis couldaccommodate his account of animal and human consciousness is shown by apassage in his exchange with Stillingfleet. As reported by Locke, Stillingfleetchallenges him directly about the relationship between his thinking-matterhypothesis and his account of the mental faculties of animals: ‘if it may be inthe power ofmatter to think, how comes it to be so impossible for such organizedbodies as the brutes have, to enlarge their ideas by abstraction?’ (LW IV 468). Aswe would expect, Stillingfleet’s challenge gave Locke little trouble. Locke initiallydenies that he ever placed thought within the natural powers of matter: hishypothesis is of course that God superadds thought to matter fitly disposed. Buthaving corrected that error, Locke responds in the way that might be expected:

But if you mean that certain parcels of matter, ordered by the divine power asseems fit to him, may be made capable of receiving from his omnipotency thefaculty of thinking; that indeed I say, and that being granted, the answer to yourquestion is easy, since if omnipotency can give thought to any solid substance, it isnot hard to conceive, that God may give that faculty in a higher or lower degree,as it pleases him, who knows what disposition of the subject is suited to such aparticular way or degree of thinking.

(LW IV 468)

Locke’s response to Stillingfleet may still leave unanswered difficulties abouthow far, and inwhat way, God’s omnipotence is constrained by the organization



of matter or ‘disposition of the subject’. But it does show that Locke thought,with some reason, that it is a virtue of the thinking-matter hypothesis that it caneasily accommodate what he takes to be the facts about human and animalmentality.

In the Essay itself, then, Locke is reticent about the metaphysical andtheological dimensions of the debate over the status of animals; in the contro-versy with Stillingfleet and in the journals, however, he is much more forth-coming. Indeed, in the replies to Stillingfleet, Locke even outlines an argumentfrom animal sensation for at least a restricted version of the thinking-matterhypothesis:

Though to me sensation be comprehended under thinking in general, yet in theforegoing discourse, I have spoken of sense in brutes, as distinct from thinking.Because your Lordship, as I remember, speaks of sense in brutes. But here I takeliberty to observe, that if your Lordship allows brutes to have sensation it willfollow either that God can and doth give to some parcels of matter a power ofperception and thinking; or that all animals have immaterial souls and conse-quently, according to your Lordship, immortal souls, as well as men; and to saythat fleas and mites, etc. have immortal souls as well as men will possibly belooked on, as going a great way to serve an hypothesis.

(LW IV 466)

Locke’s argument, then, can be reconstructed in the following form:

(1) Animals have sensations.(2) If animals have sensations, then either matter thinks in animals (by

divine superaddition) or they have immaterial souls.(3) Therefore, either matter thinks in animals (by divine superaddition) or

they have immaterial souls.(4) If animals have immaterial souls, they have immortal souls.(5) But animals do not have immortal souls.(6) Therefore, animals do not have immaterial souls.(7) Therefore, matter thinks in animals (by divine superaddition).

There is no doubt that this is a simple and elegant argument which shows howthe commonsense assumption of animal sensation can be made to serve thethinking-matter hypothesis, at least in a modest form. But though Locke showshow the argument would go, does he himself endorse the argument? Evenin the Stillingfleet controversy Locke indicates that the argument is an adhominem one; he says merely that ‘according to your Lordship’ premise (4) istrue. But of course we know from the journal entry of 1682 discussed abovethat Locke does not accept premise (4), at least when immortality is understoodin a strong sense as involving a state of sensibility. Let us return to Locke’scritique of the ‘usuall physicall proofe’ of the soul’s immortality in the journalentry:



Those who oppose these men [i.e. the proponents of the proof] presse them veryhard with the soules of beasts for say they beasts feele i.e. thinke and thereforetheir souls are immateriall and consequently immortall. This has by some menbeen judged soe urgent that they have rather thought fit to conclude all beastsperfect machins rather then allow their soules immortality or annihilation bothwhich seeme harsh doctrines, the one being out of the reach of nature and soecannot be recond as the naturall state of beasts after this life and the otherequalling them in great measure to the state of man if they shall be immortallas well as he.

(ED 121)

Here Locke shows his awareness of how the Cartesians have exploited thethesis that immateriality entails immortality to argue for the beast-machinedoctrine. But as Locke goes on to remark, parties to the debate have boughtinto a false conception of immortality; for Locke, as we have seen, immortalityis a state of sensibility, not a state of bare subsistence. And immortality in thisstrong sense is not entailed by immateriality.It seems, then, that the Stillingfleet controversy does not give us an argu-

ment for a version of the thinking-matter hypothesis that Locke is prepared toendorse; unless Locke has changed his mind since the time of the journalentry, he not merely questions, but actually rejects premise (4). It might evenbe thought that Locke provides the resources for a defence of the attribution ofimmaterial souls to animals, for he shows that such an attribution does notraise the theological difficulties that it has been supposed to raise. Locke, as itwere, can draw the sting out of such an attribution. But to view Locke’sintentions in this light would surely be a mistake. To see this, consider thefollowing Cartesian argument:

(1) If animals think (have sensations), they have immaterial souls.(2) If animals have immaterial souls, they have immortal souls.(3) But animals do not have immortal souls.(4) Therefore, animals do not have immaterial souls.(5) Therefore, animals do not think (do not have sensations).12

Locke’s aim is surely to show that the Cartesian argument is vulnerable at twopoints: not only are there grounds for questioning (1), but there are reasons forsaying that (2) is actually false, when immortality is properly understood. Andwith regard to the project of answering Stillingfleet we may say that Lockeseeks to confront him with a dilemma concerning the premise that if animalshave immaterial souls, they have immortal souls. If the premise is true, thenthere is a simple argument from animal sensation (accepted by Stillingfleet)

12 For versions of this argument, see Descartes to the Marquess of Newcastle, 23 November1646 (AT IV 575–6; CSMK III 304), and Descartes to More, 5 February 1649 (AT V 275–6;CSMK III 365–6).



for at least a modest version of the thinking-matter hypothesis. If the premiseis false, then a standard argument for immortality is blocked. Either way,Stillingfleet is forced to accept an unpalatable conclusion.

It is not surprising that Locke encourages the reader to see connectionsbetween the two anti-Cartesian polemics discussed in this chapter; for they arein a way two sides of the same coin. Locke’s complaint about the thesis that themind always thinks is that it accords too much thought to human beings; hiscomplaint about the beast-machine doctrine is that it accords too little tobeasts; indeed, it accords them none at all. And of course, as we have seen,both Cartesian doctrines exemplify the spirit of dogmatism which is preparedto override the data of experience. But Locke’s aim is not simply to uphold theclaims of observation and common sense; in both cases he seeks to show howthe falsity of the Cartesian doctrines can be exploited for metaphysical andtheological purposes. In this connection Locke’s principal aim is to sever thelink between immateriality and immortality; a subsidiary aim, it seems, is toweaken resistance to the thinking-matter hypothesis. Because of our contem-porary concerns it is no doubt the latter aim that is the more conspicuoustoday. Certainly, readers are likely to be impressed by the way in which thethinking-matter hypothesis can accommodate both animal consciousness andthe denial that the mind always thinks.



15

Berkeley, Malebranche, and Vision in God

In the second of the Three Dialogues, Hylas, the materialist, asks Philonous:‘But what say you, are not you too of opinion that we see all things in God?If I mistake not, what you advance comes near it’ (DHP II, LJ 2 214). In thefirst edition of the Dialogues Philonous’s response was a temperate one; heexpressed his agreement with Malebranche’s emphasis on the Scriptural textthat in God, we live, move, and have our being, and confined his disagreementto pointing out that, for him, the things we perceive in God are our own ideas.In the third edition, by contrast, Berkeley inserted a lengthy and rather ill-tempered expression of his differences from Malebranche:

Few men think, yet all will have opinions. Hence men’s opinions are superficialand confused. It is nothing strange that tenets, which in themselves are ever sodifferent, should nevertheless be confounded with each other by those who do notconsider them attentively. I shall not therefore be surprised, if some men imaginethat I run into the enthusiasm of Malebranche, though in truth I am very remotefrom it. He builds on the most abstract general ideas, which I entirely disclaim.He asserts an absolute external world, which I deny. He maintains that we aredeceived by our senses, and know not the real natures or the true forms andfigures of extended beings; of all which I hold the direct contrary. So that upon thewhole there are no principles more fundamentally opposite than his and mine.

(DHP II, LJ 2 214)

Presumably Berkeley felt the need to distance himself emphatically fromMalebranche in the third edition because some of his readers thought that hewas simply a disciple of the French philosopher. One early critic of Berkeley, forinstance, said that he was a Malebranchist in good faith (un Malebranchiste debonne foi).1

1 Mémoires de Trévoux, May 1713; quoted in H.M. Bracken, The Early Reception of Berkeley’sImmaterialism 1710–1733 (The Hague: Martinus Nijhoff, 1965), p. 107. Cf. C.J. McCracken,Malebranche and British Philosophy (Oxford: Clarendon Press, 1983), p. 205. In private corres-pondence Kenneth Winkler has suggested that Berkeley may have had an additional motive forinserting this passage in the third edition—namely, a desire to distance himself from the‘enthusiasm’ of the Quakers.


Is Berkeley right to insist on the distance between his own philosophy andMalebranche’s doctrine of vision in God? Or does the intemperate nature ofBerkeley’s reaction suggest that he protests too much? Now there is no doubtthat there are important affinities between the philosophies of Berkeley andMalebranche which have been documented by a number of scholars.2 Ingeneral terms, Berkeley and Malebranche both offer examples of theocentricmetaphysics of fundamentally Cartesian inspiration. Moreover, on a morespecific level, it is clear that even in his published works Berkeley is to someextent an occasionalist; he argues for the quasi-occasionalist thesis that thereare no genuine causal relationships between physical phenomena from theMalebranchian premise that there is an absolutely necessary connectionbetween a cause and its effect (PHK 31–2, 65, LJ 2 54, 69).3 Nonetheless, onthe issue of perception it may seem that there are good reasons for takingBerkeley at his word when he says that his own position is ‘ever so different’from that of Malebranche (DHP II, LJ 2 214). For one thing, though Berkeleyand Malebranche agree in defining ideas as the immediate objects of theunderstanding, they disagree fundamentally over how the definition shouldbe interpreted: whereas, for Malebranche, ideas are construed in a quasi-Platonic manner as logical concepts, for Berkeley, ideas are mental itemswhich have more in common with sense-data than with Platonic forms.Relatedly, although God is central to both theories of perception, the rolethat he is assigned seems to be quite different: whereas, for Malebranche, Godis the locus of all ideas, for Berkeley, he is the cause of ideas in finite spirits. It istempting, then, to conclude with Geneviève Brykman that, at least on the issueof perception, the similarities between Malebranche and Berkeley are al-together superficial.4 Or, in other words, it seems that Berkeley is entirelyright to insist on his distance from the doctrine of vision in God.

In this essay I shall argue that this view is mistaken. I shall show (in section I)that, in his later philosophy, Malebranche was moving towards a version of thevision in God doctrine which in some degree anticipates Berkeley’s account ofperception. I shall then show (in section II) howMalebranche is vulnerable to acritique which leads directly to Berkeley’s thesis that God is the immediatecause of our perceptual states by virtue of his will; the critique is Berkeleianinasmuch as it is strikingly isomorphic with his explicit attack on the Lockean

2 The pioneering study is A.A. Luce, Berkeley and Malebranche (Oxford: Oxford UniversityPress, 1934). Recent studies which have documented the affinities include L.E. Loeb, FromDescartes to Hume: Continental Metaphysics and the Development of Modern Philosophy (Ithaca,NY and London: Cornell University Press, 1981) and McCracken, Malebranche and BritishPhilosophy, ch. 6.

3 For Malebranche’s definition of causality, see SAT 6.2.3, OCM II 316; LO 450.4 See G. Brykman, ‘Berkeley: sa lecture de Malebranche à travers le Dictionnaire de Bayle’,

Revue internationale de philosophie 114 (1975), 496–524, esp. 504–6. Cf. J. Pucelle, ‘Berkeley a-t-il été influencé par Malebranche?’, Les Études Philosophiques 1 (1979), 38.



doctrine of material substance. I assume that if this kind of dialectical relation-ship between the two philosophers could be established, it would be sufficientto refute Philonous’s claim that there are no principles more fundamentallyopposite than Berkeley’s and Malebranche’s; for presumably not even Philo-nous would wish to make this claim about the relationship between Berkeleyand Locke. Although much of the essay will be devoted to rational reconstruc-tion, we shall also focus on Berkeley’s own criticisms of Malebranche; inparticular, I shall show (in section III) how Malebranche’s doctrine of visionin God is one of the targets of Berkeley’s polemic against abstract ideas. As weshall see, the fact that Malebranche is a target suggests that the nature of thisfamous polemic may have been misunderstood by philosophers.

I

The affinities between Berkeley and Malebranche are not evident as long as weconcentrate onMalebranche’s earliest and best-known account of vision in God.In his later philosophy Malebranche significantly modified the doctrine whichhe had expounded in The Search After Truth; indeed, according to some Frenchcommentators, the modifications are so significant that the later theory is not somuch a theory of vision enDieu as of vision par Dieu.5 I therefore need to explainhow Malebranche modified his theory of vision in God in his later writings.Malebranche’s first version of vision in God takes roughly the following

form. When I perceive a physical object, such as the table in front of me, mymind is directly related to a geometrical idea in God. It is by virtue of beingrelated to the idea or concept of a rectangle in God that I am able to perceivethe table as a rectangular object. Since ideas, for Malebranche, are logicalconcepts, not sense-data, they can be grasped only in an act of intellectualawareness; thus something else is needed to explain what makes my percep-tion of the table a case of sense-perception rather than a case of abstractthought. Malebranche explains that any act of sense-perception involves notjust the apprehension of an idea but the presence of sensations (sentiments) aswell. Sense-perception is thus a combination of two heterogeneous elements:

When we perceive something sensible, two things are found in our perception:sensation and pure idea. The sensation is a modification of our soul, and it is Godwho causes it in us. He can cause this modification even though He does not haveit himself because He sees in the idea He has of our soul, that it is capable of it. Asfor the idea found in conjunction with the sensation, it is in God, and we see it

5 See, for example, A. Robinet, Système et existence dans l’oeuvre de Malebranche (Paris: Vrin,1965), pp. 262–3.


Berkeley, Malebranche, and Vision in God 231

because it pleases God to reveal it to us. God joins the sensation to the idea whenobjects are present so that we may believe them to be present and that we mayhave all the feelings and passions that we should have in relation to them.

(SAT 3.2.6, OCM I 445; LO 234)

It seems clear that, for Malebranche, it is our relationship to ideas which playsthe major role in sense-perception here. In the first place, ideas are the onlyimmediate objects of perception: sensations (sentiments) are not objects at allbut merely adverbial modifications of the mind. Secondly, it is ideas whichrepresent to us the primary qualities of bodies, and for Malebranche, as a goodCartesian, these are the only properties that bodies truly possess; secondaryqualities are not genuine physical properties but purely mind-dependentsensations. Even if Malebranche sometimes speaks of our having sensationsof primary qualities, he nonetheless holds that sensations are not sufficient forsense-perception: as the above passage shows, sense-perception crucially re-quires the application of concepts or, in his terms, ‘ideas’.6

In its first form, then, the doctrine of vision in God is not a causal theory ofperception. The point is worth emphasizing, since it may be obscured bysuperficial similarities with a familiar version of the causal theory, such asLocke’s.7 Locke and Malebranche agree in holding that the immediate objectsof perception are ideas, but beyond that they part company.Whereas, for Locke,the ideas to which we have access in sense-perception are mental effects ofexternal objects, for Malebranche they are neither in our minds nor are theyeffects of any kind. On the contrary, they are logical concepts, located in God, towhich we are (non-causally) related in an act of intellectual awareness.8 It is truethat sentiments are also elements of any act of sense-perception and sentimentsare indeed mental items which are caused by God. But, as we have seen,sentiments are not themselves objects of eithermediate or immediate awareness.

In his later philosophy, however, Malebranche comes to adopt a theologicalversion of the causal theory of perception. After 1695 Malebranche introducesthe notion of the efficacious idea (idée efficace); that is, ideas in God are saidto possess causal powers.9 In terms of this notion he introduces two main

6 Cf. S. Nadler, Malebranche and Ideas (Oxford: Oxford University Press, 1992), pp. 167–73.The fact that for Malebranche sense-perception involves a conceptual or cognitive componentmarks a contrast with Berkeley’s theory of perception. Certainly Berkeley is explicit thatperception does not involve judgement: see, for example, Theory of Vision Vindicated, para.42, LJ 1 265. Berkeley’s stance on this issue is consistent with his denial that Malebranchianideas play a role in perception. On this issue, see sections II and III of this chapter.

7 For a helpful account of the differences between Malebranche’s and Locke’s theory ofperception, see H.E. Matthews, ‘Locke, Malebranche and the Representative Theory’, inI.C. Tipton (ed.), Locke on Human Understanding (Oxford: Oxford University Press, 1977),pp. 55–61.

8 This is the valid point made by Brykman and Pucelle, but they do not note that it holds onlywith regard to the earlier philosophy.

9 Cf. A. Robinet, Système et existence, p. 259.



innovations in his theory of perception. First, the intentional relation betweenthe human mind and the idea in God is now construed as a causal relation.Thus, when I perceive the table, the idea of a table causes an act of perceptualawareness. Secondly, Malebranche no longer insists on the earlier distinctionbetween ideas and sentiments or sensations. Formerly, he had appealed toideas only to give an account of the mind’s perception of primary qualities;now he invokes them to explain the experiences of sensations and secondaryqualities. Differences in mental states—for example, between conceiving of arectangular figure and sensibly perceiving a rectangular figure such as mytable-top—are now explained in terms of the different ways in which one andthe same idea in God affects our minds. In the Dialogues on Metaphysics, forinstance, Malebranche’s spokesman, Theodore, says that ‘there is one and onlyone idea of a hand . . . an idea which affects us in different ways, which acts onour souls and which modifies the soul with heat, colour, pain etc.’ (DMR V.5,OCM XII 116; JS 77). In a late revision to the Christian ConversationsMalebranche writes of the idea of extension rather than the idea of a kind ofphysical object, but otherwise he offers a similar explanation:

When the idea of extension affects or modifies the mind with a pure perception,then the mind simply conceives extension. But when the idea of extensiontouches the mind in a livelier fashion, and affects it with a sensible perception,then the mind sees or senses extension. The mind sees it [extension] when thisperception is a sensation of colour; and it sees or perceives it in a still more livelyfashion when the perception with which intelligible extension modifies it is apain. For colour, pain, and all the other sensations are only sensible perceptionsproduced in intelligences by intelligible ideas.

(OCM IV 75–6)

Although Malebranche is not explicit on this point, presumably he intendshere to offer a philosophical analysis of the distinction between conceiving andsensibly perceiving; the difference between these two kinds of mental states isactually constituted by the more or less lively way in which God’s ideas act onthe human mind.The theory of efficacious ideas which is a hallmark of Malebranche’s later

philosophy is apt to strike readers as bizarre, but it is not a gratuitousinnovation. Indeed, it is possible to see the introduction of the theory as aresponse to the pressure of two problems. First, Malebranche insists that inseeing all things in God, the mind is somehow united to God, and he had beenpressed by Regis to explain the nature of the union (OCM XVII-1 293–4).Malebranche seems to have come to the conclusion that the only way ofmaking sense of this union was in causal terms. Secondly, as I have arguedelsewhere, Malebranche came to feel that his early commitment to the Carte-sian theory that the mind has a faculty of pure intellect was inconsistent withhis Augustinian conviction that the mind is not a light to itself; according to



Malebranche, the mind is a lumen illuminatum, not a lumen illuminans.10 Buthaving abandoned the Cartesian theory of pure intellect, Malebranche neededsomething to put in its place; causally efficacious ideas fill this role byexplaining how a purely passive mind is in touch with God’s ideas.

Malebranche’s first version of the vision in God is not wholly withoutaffinities with Berkeley; for the two philosophers agree in assigning to God acentral role in the theory of perception. Nonetheless, it is clearly the secondversion of the doctrine of vision in God which offers the more fruitful basis fora comparison. Unlike the earlier version, the later version is a kind of causaltheory according to which it is God’s ideas (rather than physical objects)which are causally responsible for our perceptual states. Moreover, the secondversion of the vision in God differs from the first in treating our experiences ofprimary and secondary qualities as having the same causal source. In boththese respects Malebranche is moving at least some steps in the directiontowards the theory of perception which Berkeley himself espouses. But clearlyMalebranche and Berkeley are still some distance apart, for they disagreeabout the nature of God’s causality; unlike Malebranche, who ascribes efficacyto divine ideas, Berkeley holds that God is the direct and immediate cause ofall our perceptual states by virtue of his will: ‘I say, the things by me perceivedare known by the understanding, and produced by the will of an infinite spirit’(DHP II, LJ 2 215). I now wish to show how one can arrive at Berkeley’sposition concerning the causality of our perception by a thoroughly Berkeleiancritique of Malebranche’s later version of the doctrine of vision in God. I shalluse the adjective ‘Berkeleian’ to indicate that while it employs a strategyfamiliar from his case against Locke, the line of argument I shall outlineinvolves a large element of rational reconstruction. Nonetheless, we shall seethat, at points, the critique makes direct contact with Berkeley’s text; it makesuse of Berkeley’s own explicit objections to the doctrine of vision in God.

II

Let us begin by recalling Berkeley’s strategy of argument against the Lockeantheory of matter, or material substance. In the Second Dialogue Philonoushelpfully and succinctly reviews its main features for benefit of the reader:

phil. And does notmatter, in the common current acceptation of the word, signify anextended, solid, moveable, unthinking, inactive substance?

hyl. It doth.

10 Cf. chapter 3 in this volume.



phil. And hath it not been made evident that no such substance can possibly exist?And though it should be allowed to exist, yet how can that which is inactive be acause of thought? (DHP II, LJ 2 215)

Berkeley thus indicates that he has two strings to his bow in the case againstLocke; he seeks to argue for both a strong thesis and a weaker, fall-back position.

(1) Material substance cannot exist.(2) Even if material substance existed, it could not have the power of

causing perceptions.

By analogy, then, a Berkeleian critique of the later version of the vision in Godwould take the following form:

(1') Ideas in God (as Malebranche conceives them) cannot exist.(2') Even if such ideas existed, they could not have the power of causing

perceptions.

There is no direct evidence that Berkeley was familiar with Malebranche’s laterversion of the vision in God, according to which ideas in God have the powerto cause perceptions in human minds; thus Berkeley offers no argumentfor (2').11 However, the situation is very different with regard to the strongerthesis; in the Dialogues Philonous offers an explicit argument for (1'). We shallbegin, then, by looking at the arguments that might be made on Berkeley’sbehalf for (2'), and then turn to an analysis of Berkeley’s own case for (1').We have seen that the theory of efficacious ideas which distinguishes the

later version of the vision in God is not a gratuitous innovation; it is a responseto genuine philosophical and theological problems. Nonetheless, the theoryseems distinctly vulnerable to criticisms of the sort which Berkeley levelledagainst the Lockean doctrine of material substance; for Malebranche, ideas arenot mental items but logical concepts, and it is hard to see how such ‘thirdrealm’ entities can have any causal powers. Malebranche’s only answer to thisobjection is an argument of the following form: ideas are in God; everything inGod is causally efficacious; hence, ideas themselves are causally efficacious (tode Mairan, 12 June 1714, OCM XIX 884). But it is not clear that Malebrancheis really entitled to the second premise. Of course, it would be unfair andanachronistic to confront Malebranche with the Kantian objection that noth-ing can be a cause which is outside the spatio-temporal framework, but even interms of Malebranche’s own system, it seems that there are reasons fordenying causal efficacy to ideas. According to Malebranche’s central argument

11 Berkeley is thought by some (e.g. by Luce, Berkeley andMalebranche, p. 4, n. 1) to have readMalebranche’s Search After Truth in the second edition of the English translation by ThomasTaylor published in 1700; this English translation was based on the fourth French edition of LaRecherche de la Vérité, published in 1678. It was not until the sixth edition, published in 1712,that Malebranche incorporated references to his later theory of efficacious ideas.



for occasionalism, true causality implies a necessary connection between acause and its effect, and it is Malebranche’s contention that there is such anecessary connection only between the will of God and its upshot (SAT 6.2.4,OCM II 316; LO 450). For Malebranche the occasionalist, then, God is theonly genuine cause by virtue of having an omnipotent will, not by virtue ofbeing the region of ideas. Thus, the theory of ideas can be convicted ofsomething like a category mistake. It is perhaps concerns of this kind whichhave led some scholars (e.g. Alquié) to wonder whether Malebranche doesmean to attribute efficacy to ideas themselves, as opposed to God’s will.12 Butthe textual scruples are unfounded, though the philosophical ones whichunderlie them are clearly justified.

When we turn to the strong thesis (1'), we make direct contact with Berke-ley’s own text. Through his spokesman, Philonous, Berkeley offers an argumentwhich seeks to show that Malebranchian ideas in God cannot exist: ‘I do notunderstand how our ideas, which are things altogether passive and inert, can bethe essence, or any part (or like any part) of the essence or substance of God,who is an impassive, indivisible, purely active being’ (DHP II, LJ 2 213–14).According to Berkeley, then, Malebranche’s theory of ideas in God is incoher-ent theology; ideas are supposed to constitute the essence of God, but their inertand passive character prevents them from fulfilling this role.

As it stands, this line of criticism is not entirely satisfactory, thoughsomething may perhaps be made of it. In the first place, consider Berkeley’sclaim that ideas are altogether passive and inert.13 The later Malebranchewould of course dispute this characterization of ideas; in his view, ideas havethe power to cause perceptions in finite minds. As we have seen, though, in hislater philosophy Malebranche defends the causal efficacy of ideas, he does notreally succeed in defending the thesis against the charge of incoherence. ThusBerkeley could say that, in Malebranche’s philosophy, it is not clear how ideascan be other than passive and inert (in the sense of lacking causal powers).

Secondly, is Berkeley right to claim that, for Malebranche, ideas constitutethe essence of God? On this issue Malebranche’s position is not entirely clear,but at least it is a matter to which he devoted some care; he characteristicallyclaims that ideas constitute the essence of God, not absolutely, but only in acertain respect; they constitute his essence only insofar as he is participable bycreatures (SAT, Elucidation X, OCM III 149; LO 625). Thus Malebranchewould no doubt seek to claim that this qualification is sufficient to draw theteeth of Berkeley’s objection. Of course if Malebranche could successfullydefend his theory of efficacious ideas, there is no reason why he should beembarrassed by the admission that ideas constitute the essence of God; for he

12 See F. Alquié, Le Cartésianisme de Malebranche (Paris: Vrin, 1974), pp. 210–11.13 Berkeley of course ascribes passivity and inertness to ideas in his own philosophy: see PHK

25, LJ 2 52.



would then be committed to the thesis that the essence of a wholly active beingis constituted by that which is active (efficacious ideas), and such a positionwould not be vulnerable to Berkeley’s charge of incoherence. But if he fails toshow how ideas can be causally active, it seems that Malebranche must find away of denying that ideas constitute God’s essence.So far, then, the debate over Berkeley’s strong thesis (1') seems something of

a stalemate. Berkeley seems justified in saying that Malebranchian ideas inGod are really passive (in the sense of lacking causal efficacy), but he has notconclusively shown that, for Malebranche, they constitute God’s essence. Weshall now see that Berkeley has other grounds for supporting his strong thesis,having to do with his polemic against abstract ideas.

I II

Berkeley famously begins The Principles of Human Knowledge with an attackon the doctrine of abstract ideas. Typically, the textbooks tell us that theprincipal and perhaps only target of this attack is Locke, and there is nodoubt that Locke is the sole champion of abstract ideas whom Berkeley citesin the Principles (Introduction 11–13, LJ 2 30–3);14 it is Locke whom Berkeleychooses to quote when he wants an account of the mental process by whichwe are supposed to frame abstract ideas. But notice that Berkeley does not saythat Locke is the only target of his polemic; on the contrary, the perniciousdoctrine of abstract ideas is supposed to be the common property of a numberof philosophers.15 Indeed, on the assumption that Locke is the only target ofattack, the vehemence and placing of the polemic are hard to understand; thedoctrine of abstract ideas does not seem to occupy an absolutely centralposition in Locke’s thought.16 I would like to suggest that a possible explan-ation for the prominence and the vehemence of the attack is that Berkeley hasanother target in his sights—namely, Malebranche’s theory of ideas in God.It is true that such a thesis receives no direct textual support from thePhilosophical Commentaries; though Malebranche’s name is frequently citedthere, it is in connection with issues other than abstract ideas. But even if

14 Locke is called ‘a late deservedly esteemed philosopher’ (LJ 2 30).15 In the draft Introduction, Berkeley names Aristotle, the Schoolmen, ‘and all others,

whether Ancient or Modern Logicians and Metaphysicians’ as partisans of the doctrine ofabstract ideas. See B. Belfrage (ed.), George Berkeley’s Manuscript Introduction (Oxford: Doxa,1987), pp. 67 and 93. Cf. Berkeley’s letter to Samuel Johnson, 24 March 1730, LJ 2 293: ‘Abstractgeneral ideas was a notion that Mr Locke held in common with the Schoolmen, and I think allother philosophers.’

16 For a revised estimate of the role of abstract ideas in Locke’s theory of knowledge, seechapter 13 in this volume.



Berkeley did not mean to attack Malebranche’s theory of ideas while writingthe Principles, there is no doubt of his intentions by the time of the thirdedition of the Dialogues; the Malebranchian theory falls explicitly within thescope of the polemic against abstract ideas.17 For, as we have seen, one of theways in which Berkeley seeks to distance himself from the French philosopheris by claiming that Malebranche ‘builds on the most abstract general ideaswhich I entirely disclaim’. Here the context makes it crystal clear that it isideas in God which are in question.

Berkeley’s claim that Malebranche builds on the most abstract general ideasraises an interesting puzzle. At first sight it is difficult to see how Berkeleycould think that it is appropriate to describe Malebranche’s ideas in Godas abstract. For there are obvious differences between Malebranchian ideasin God and the abstract ideas which Berkeley found, and attacked, in Locke.It is true of course that, in terms of content, there are certain similarities:Locke’s most famous example of an abstract idea is the idea of a triangle, andMalebranche too would probably cite geometrical concepts if he were asked togive an example, in terms of content, of an idea in God. Moreover, Male-branche’s ideas in God, like Locke’s abstract ideas, are typically, and perhapsessentially, universals. But what is distinctive of abstract ideas in their Lockeanform is that they are psychological entities which are the products of a mentalprocess; Locke famously describes how the abstract general idea of a triangle isformed by a process which requires ‘some pains and skill’ (Essay IV.vii.9).Indeed, such is the degree of pains and skill required for the formation ofabstract general ideas that, according to Locke, it is beyond the capacities ofsmall children. At least on one account, the process which Locke describesinvolves leaving out of our idea of a triangle everything except that which iscommon to all triangles. By contrast, the ideas in God which are at the heart ofMalebranche’s doctrine of vision in God are not products of a mental processof abstraction; indeed, they are not to be regarded as mental entities of anykind but rather, as we have seen, as logical concepts—i.e. third-realm entities.It would be perfectly accurate to describe Malebranche’s ideas in God asabstract entities—i.e. entities which are not in space or time—but to supposethat they are abstract ideas in the sense in which Lockean abstract ideas areabstract is to be guilty of something like a bad pun. It is natural to wonder,then, how Berkeley could possibly imagine that Malebranche’s ideas in Godare in any way damaged by his polemic against Lockean abstract ideas. It may

17 My thesis has been partly anticipated by Kenneth Winkler, who sees that Berkeley’scritique of the doctrine of abstract ideas applies to Malebranche as well as Locke. SeeK.P. Winkler, Berkeley: An Interpretation (Oxford: Clarendon Press, 1989), pp. 68–9. Winklerpoints out that there are both ‘empiricist’ and ‘rationalist’ versions of the doctrine of abstraction.I disagree with Winkler to the extent that within the ‘rationalist’ camp one can distinguishbetween those, like Descartes, who regard ideas as mental items and those, like Malebranche,who regard them as logical concepts.



seem that either Berkeley is indulging in empty rhetoric or he is guilty of agross philosophical error.In reality, the puzzle can be solved in a way that does credit to Berkeley’s

philosophical acumen. It is true thatMalebranche’s ideas inGod are not productsof amental process of abstraction, and there is no reason to suppose that Berkeleywas unaware of this fact. Rather, the appropriate moral to draw from Berkeley’sattack onMalebranche is that the psychological character of abstract ideas is notone of their essential features. It is of course a feature of Lockean abstract ideas,but, with respect to abstract ideas in general, it is, for Berkeley, only a contingentfeature. Thus, the distinction between abstract and non-abstract ideas cuts rightacross the distinction between logic and psychology.18

To see how Berkeley was justified in including Malebranche in the scope ofhis polemic, consider two logically distinct objections that he makes in thePrinciples against the doctrine of abstract ideas. In the first place, there is theindeterminacy objection: an abstract idea of a triangle is supposed to be the ideaof a triangle in general; in other words, it is the idea of a triangle which is neitherscalene, nor isosceles, nor equilateral. For Berkeley, of course, any particularexisting triangle must be fully determinate. Now Berkeley further acceptsthe principle that if an object is impossible in reality, it is also impossible inthought; it follows, then, that the idea of a triangle in general—that is, the ideaof an indeterminate triangle—is impossible. As Berkeley explains in the draftIntroduction to the Principles of Human Knowledge:

It is, I think, a receiv’d axiom that an impossibility cannot be conceiv’d. For whatcreated intelligence will pretend to conceive, that which God cannot cause to be?Now it is on all hands agreed, that nothing Abstract or General can be made reallyto exist. Whence it should seem to follow, that it cannot have so much as an Idealexistence in the understanding.19

Secondly, there is the inconsistency objection. Exploiting some possiblyincautious phrasing in Locke, Berkeley takes his opponent to be saying thatthe abstract idea of a triangle is the idea of a triangle which is simultaneouslyscalene, isosceles, and equilateral (Essay IV.vii.9).20 Again, since such an objectis impossible in reality, it is also impossible in thought.

18 If this conclusion seems too strong, we can say that Berkeley’s central objections to abstractideas do not turn on their being products of a psychological process. In that case Malebranchianideas in God would not strictly be abstract ideas, but they would share an objectionable featurewith abstract ideas. But it worth emphasizing that the textual evidence favours the strong claim.

19 Belfrage (ed.), Berkeley’s Manuscript Introduction, p. 75.20 J.L. Mackie, Problems from Locke (Oxford: Clarendon Press, 1976), thinks that it is not

strictly accurate of Locke to say that the idea of a triangle is ‘all and none of these at once’(p. 116). Certainly Locke is shifting here without warning from the extensional to the intensionalpoint of view. It should also be noticed that, contrary to what Berkeley suggests, Locke does notspeak of putting together inconsistent parts of different ideas, but of putting together ‘some partsof several different and inconsistent ideas’ (Essay, IV.vii.9).



Berkeley thus has two main objections against the doctrine of abstract ideas,and it seems clear that, of these two, the second has no purchase againstMalebranche. It would be quite implausible to suppose that, for Malebranche,the abstract idea of a triangle in God is the idea of a figure which combinesinconsistent features. Fortunately, there is no reason to suppose that Berkeleysought to pin this objection on to Malebranche. By contrast, the indetermin-acy objection is highly relevant to Malebranche’s theory of ideas. One couldsay of the idea of a triangle in God for Malebranche what Locke said of theabstract idea of a triangle: ‘it is something imperfect [i.e. indeterminate] thatcannot exist’ (Essay IV.vii.9); in other words, no particular existing trianglecould instantiate only those properties contained in the general idea of atriangle. To say that the indeterminacy objection is relevant to the case ofMalebranche’s ideas is not of course to concede that the objection has the forcewhich Berkeley believed it to have; it is only to say that indeterminacy is asmuch a feature of Malebranchian general ideas in God as of Lockean abstractideas. It is a further question whether Berkeley is right to accept the principlethat whatever is impossible in reality is impossible in thought.

At this stage a possible objectionmust be faced. It may be urged that, even onmy own showing, Berkeley cannot coherently have supposed that Malebran-chian ideas in God fall within the scope of the polemic against abstract ideas.For, as we have seen, Berkeley’s arguments against abstract ideas appeal to theprinciple that whatever is impossible in reality is impossible in thought; bymeans of this principle, Berkeley seeks to move from the premise that a certainobject—e.g. an imperfect or inconsistent triangle—is impossible in reality, tothe conclusion that it is impossible in thought. And this shows that the polemicis directed against a theory of abstract ideas which views them as psychologicalentities: Berkeley is essentially concerned to establish that abstract ideas arepsychologically impossible. Thus the polemic can have no relevance to a theoryof ideas, such as Malebranche’s, which views ideas as logical concepts. But thisobjection is misguided. It is true that Berkeley seeks to show that certain itemsare impossible in thought: as he puts it, they cannot have an ideal existence inthe understanding. But what this means is that certain items are impossible asobjects of thought; and this claim does not entail that an object of thought isitself a psychological product; all it entails is that it is capable of being appre-hended by psychological states or processes. Thus Berkeley’s arguments can becoherently directed against a theory according to which abstract ideas are notpsychological entities—not psychological products—but logical concepts.

Berkeley, then, was right to believe that theMalebranchian doctrine of visionin God falls within the scope of his polemic against abstract ideas; Male-branche’s ideas in God share the objectionable indeterminacy of Lockeanabstract ideas. Such a defence of Berkeley leads to the rather striking resultthat the target of his polemic may have been somewhat misidentified over theyears. In the Introduction to the Principles Berkeley may have concentrated his



attack on Locke’s account of the psychological processes by which abstractideas are formed, but such an attack will not serve all Berkeley’s purposes; as wehave seen, he is equally opposed to abstract ideas which are not psychologicalproducts of any kind. Indeed, the process of abstraction is a much less centraltarget of Locke’s polemic against abstract ideas than has been realized.21

We have seen, then, that in the Dialogues Berkeley presents a somewhatdisingenuous account of his relationship to Malebranche. His theory of per-ception has much more in common with the vision in God, at least in its laterversion, than he is ready to admit.Malebranchian ideas inGod are abstract, andmust thus be eliminated, but the two philosophers agree in advocating atheological version of the causal theory of perception. To draw attention tothis similarity is not of course to deny that there are still important remainingdifferences between the two philosophers which I have not discussed. AsPhilonous reminds us, Malebranche asserts an absolute external world whichBerkeley denies. It is no part of the thesis of this essay that Malebrancheanticipates Berkeley’s reductive phenomenalist account of bodies. From thestandpoint of ontology there is thus a major difference between the twophilosophers. But from the standpoint of the theory of perception, this meta-physical difference between Berkeley and Malebranche is not important, for asPhilonous observes, on Malebranche’s theory of vision in God, the externalphysical world is simply idling (DHP II, LJ 2 214). For the purposes of thisessay, the fact that Malebranche asserts the existence of an external physicalworld, and Berkeley denies it, may be regarded as a rather trivial matter.

21 Cf. Winkler: ‘His objection to abstract ideas is not that there is something wrong with theprocess of abstraction . . . but that there is something wrong with the product’ (Berkeley, p. 69).



16

Berkeley and Malebranche onCausality and Volition

‘Strange impotence of men. Man without God. Wretcheder than a stone ortree, he having onely the power to be miserable by his unperformed wills, thesehaving no power at all’ (PC 107, LJ 1 18). As this passage from the Philosoph-ical Commentaries shows, the young Berkeley seems to have been attracted toa form of occasionalism; in other words, he seems to have felt the pull of thedoctrine that creatures are causally powerless and that God alone is a truecause. Yet, as is well known, in his published writings, unqualified occasional-ism is not Berkeley’s mature philosophical position, at least not officially. Onthe contrary, in his published writings Berkeley maintains that, in addition toGod, finite spirits are true causes; they exhibit genuine causality in bothimagination and voluntary physical movement. In the Philosophical Commen-taries Berkeley had signalled his departure from occasionalism with a signifi-cant entry: ‘Wemove our legs ourselves. ‘tis we that will the movement. HereinI differ from Malbranch’ (PC 548, LJ 1 69).

Berkeley’s departure from strict occasionalism is something of a puzzle, for interms of philosophical consistency, it seems to represent a change for the worse.The claim that finite spirits are causally active in willing is important to Berkeley,but it is a source of serious strains in his mature system. For one thing, the claim isin tension with a residue of occasionalist assumptions concerning causality whichis found even in the published works. More surprisingly, it sits uneasily withBerkeley’s principal philosophical innovation, namely immaterialism; indeed,immaterialism seems to push Berkeley in the direction of occasionalism. ThusBerkeley faces special problems in accommodating the claim that finite spirits aretrue causes. In sections I and II of this essay I shall set out the nature of the problemand examine the pressures towards occasionalism in Berkeley’s metaphysics. Insections III and IVof the essay I shall try to explainwhyBerkeley felt it necessary todepart from Malebranche’s teaching concerning causality by insisting that finitespirits cannot be genuine causes. This will require us to look beyond purelyphilosophical arguments to the theological concerns which underpin his meta-physics. But first of all, let us look briefly at the occasionalism of Malebranche.


I

There are a number of routes to occasionalism in seventeenth-century phil-osophy; different philosophers were attracted by different arguments, or wherethey used the same arguments, they differed in the weight they gave them.Some philosophers argued that if Descartes’ doctrine of continuous creation isthought through, there is no room left for secondary causes; all causal activitymust be ascribed to God alone.1 Such an argument seems to rely on theassumption that there is no causal overdetermination. Others, such as Geu-lincx, made heavy use of the principle that if A is the cause of B, then A knowshow to bring about B; as Geulincx puts it, ‘Ego non facio quod quomodo fiatnescio’ [I do not make (i.e. cause) what I do not know how to make (cause)].2

Here I am concerned only with what is perhaps the most interesting andpowerful argument for strict occasionalism, namely the argument from thedefinition of strict causality in terms of necessary connection. According toMalebranche, ‘a true cause as I understand it is one such that the mindperceives a necessary connection between it and its effect’ (SAT 6.2.3, OCMII 316; LO 450). ForMalebranche, God satisfies this definition of true causality,for God is, by definition, omnipotent, and in the case of an omnipotent being, itis logically necessary that what such a being wills should occur. Thus Male-branche seems to subscribe to the following principle concerning God:

Necessarily, for any logically possible state of affairs p, if God wills that p, then p.

In the case of finite substances, however, there is no logically necessary con-nection between those events which we take to be related as cause and effect. Itis not logically necessary, for instance, that the linen should dry when placednear the fire. In the special case of the mind–body relation, it is not logicallynecessary that my arm should go up when I will to raise it; it is conceivable thatI should suddenly be afflicted with paralysis. So Malebranche consistentlyconcludes that my will is not the true cause of my physical movements:

Now it appears to me quite certain that the will of minds is incapable of movingthe smallest body in the world; for it is clear that there is no necessary connectionbetween our will to move our arms, for example, and the movement of our arms.It is true that they are moved when we will it, and thus that we are the naturalcause of the movement of our arms. But natural causes are not true causes; theyare only occasional causes that act only through the force and efficacy of the willof God.

(SAT 6.2.3, OCM II 315; LO 449)

1 See, for instance, C.J. McCracken, Malebranche and British Philosophy (Oxford: ClarendonPress, 1983), ch. 3, esp. pp. 93–4.

2 McCracken, Malebranche and British Philosophy, p. 105.


Berkeley and Malebranche on Causality and Volition 243

Today, of course, it is natural to object that while genuine causal connectionsare indeed necessary, the necessity in question is not logical. ButMalebranche’smistake, if it is one, is not a mere surface muddle; it is a mistake of a deep kind.Certainly in the period before Hume there was nothing eccentric about Male-branche’s analysis of the concept of true causality, and to many readers thisargument for occasionalism must have appeared a powerful one. Indeed, asLoeb notes, if one grants Malebranche’s analysis of causality in terms of(logically) necessary connection, the argument is even persuasive.3

I I

In the Principles of Human Knowledge Berkeley famously argues that many ofthe things we take to be causes are not causes at all:

the connexion of ideas does not imply the relation of cause and effect, but only ofa mark or sign with the thing signified. The fire which I see is not the cause of thepain I suffer upon my approaching it, but the mark that forewarns me of it. In likemanner, the noise that I hear is not the effect of this or that motion or collision ofthe ambient bodies, but the sign thereof.

(PHK 65, LJ 2 69)

Such supposed causes as the fire are thus signs by which God communicateswith us, and God himself is the true efficient cause in these cases. Thus, evenin his mature philosophy, Berkeley remains something of an occasionalist.Although he no longer holds that finite spirits are impotent, at least withrespect to physical processes Berkeley continues to teach that true causalitymust be ascribed to God alone; he is also prepared to concede that the ‘signs’,such as the fire, can be called occasional causes (to Samuel Johnson, 25November 1729, LJ 2 280).

Why does Berkeley hold this remarkable view of physical processes? Berke-ley is not very forthcoming on this issue; but he seems to be in the grip of aMalebranchian argument; indeed, he appears to have in mind the argumentfrom necessary connection. In an earlier passage in the Principles Berkeleymakes an explicit reference to necessary connection:

That food nourishes, sleep refreshes, and fire warms us; that to sow in the seed-time is the way to reap in the harvest, and in general, that to obtain such or suchends, such or such means are conducive, all this we know, not by discovering anynecessary connexion between our ideas, but by the observation of the settled lawsof nature, without which we should be all in uncertainty and confusion, and a

3 L.E. Loeb, From Descartes to Hume: Continental Metaphysics and the Development ofModern Philosophy (Ithaca, NY and London: Cornell University Press, 1981), p. 205.



grown man no more know how to manage himself in the affairs of life, than aninfant just born.

(PHK 31; LJ 2 54)

Berkeley thus stresses the contingency of the regularities which we take to becausally related; as Bennett says, he seems to want to highlight the inductivenature of our knowledge of them.4 It is natural to suppose, then, that Berkeleyis committed to the doctrine that genuinely causal connections, by contrast,must be knowable a priori. But if this is Berkeley’s position, then it posesproblems for his differential treatment of bodies and spirits with respect tocausality; it seems to imply that the volitions of finite spirits cannot begenuinely causal. For, as Hume was to observe, we can no more have a prioriknowledge of the effects of volitions than of the effects of bodies; it is no morepossible for me to know a priori that my arm will go up when I will to raise itthan that the kettle will boil shortly after I light the gas under it. The two kindsof cases are on a par; in each we are dependent on experience:

The influence of volition over the organs of the body . . . is a fact which, like allother natural events, can be known only by experience, and can never be foreseenfrom any apparent energy or power in the cause which connects it with the effect,and renders the one an infallible consequence of the other. The motion of ourbody follows upon the command of our will. But the means by which this iseffected . . .must for ever escape our diligent enquiry.

(E 52)

Jonathan Bennett has made an interesting attempt to defend Berkeley againstHumean strictures here: he seeks to show that, on his own principles, Berkeleycan consistently claim that finite spirits are causally active while denying thatfires make kettles boil. Bennett suggests that, despite appearances, Berkeley isnot in fact committed to the thesis that causal connections must be knowable apriori; however, according to Bennett, Berkeley does deny that they can beknown only on an inductive basis. Bennett’s way of combining these twoclaims is as follows:

If I know that I am about to scratch my elbow, having just decided to do so, it isplausible to say that my knowledge—though not a priori, not knowledge of alogically necessary consequence of my decision—is not inductively based either.5

Following Hart and Hampshire, Bennett suggests that this knowledge aboutone’s future actions is based on reasons, which is decision. Thus, in the eyes ofBennett, Berkeley is entitled to assert the asymmetry, in respect of causality,between arm-raising and boiling kettles.

4 Jonathan Bennett, Locke, Berkeley, Hume: Central Themes (Oxford: Clarendon Press, 1971),pp. 201–2.

5 Bennett, Locke, Berkeley, Hume, p. 202.



This is an intriguing line of defence, but as Bennett admits, it faces textualdifficulties.6 Berkeley says things in places which suggest that our knowledge ofthe relation between volition and upshot is inductively based after all; with regardto imagination, for instance, Berkeley writes: ‘I find I can excite ideas inmymindat pleasure, and vary and shift the scene as often as I think fit. It is no more thanwilling, and straightway this or that idea arises inmy fancy. This much is certain,and grounded upon experience’ (PHK 28, LJ 2 53). Following Bennett, I believethat, on the most natural reading, this passage asserts that the relation betweenvolition and upshot can be known only on an inductive basis. As Bennett puts it:‘I find “by experience” that certain volitions are attended or followed by certainupshots, and I trust (in God) that this correlation will continue to hold in thefuture.’7 But in that case it looks as if, by Berkeley’s lights, the relation cannot begenuinely causal. So it seems that Berkeley has difficulty maintaining the asym-metry between physical processes and the volitions of finite spirits. In spite ofhimself he gets pulled back into unqualified occasionalism.

Pressure towards occasionalism, at least with regard to voluntary physicalmovements, is also exerted by Berkeley’s immaterialism. As we have seen, inthe Commentaries Berkeley comes to insist, against Malebranche, that wemove our limbs ourselves; and this claim is stressed not just in the Principlesand the Dialogues but also in later works (De Motu 25, LJ 4 37; Siris 161, LJ 585). Yet a little reflection on Berkeley’s immaterialism suggests that he is notreally entitled to make such a claim: to put the point another way, it is not clearthat Berkeley is in any better position than Malebranche to attribute to the willcausal power over the movement of our limbs. Consider how Berkeley mustanalyse the case of my raising my arm to scratch my ear. Berkeley will say thatI perform a volition, and that the upshot of this volition is that my arm goesup. Now, for Berkeley, to say that my arm goes up is simply to talk aboutchanges in the sensory state of myself and other perceivers. But this change insensory state is not brought about by me but by God, for sensory ideas arecausally independent of my will (PHK 29, LJ 2 53); God changes my ideas andthose of other perceivers so that we have the appropriate sensations as of myarm going up.8 But Berkeley is not in a position to say that my volitiongenuinely causes God to perform the appropriate actions; surely I cannotcause God to do anything. Rather, as Taylor says, my volition seems morelike a signal to God to exercise his causal power in a particular way; in other

6 Bennett, Locke, Berkeley, Hume, pp. 206–7.7 Bennett, Locke, Berkeley, Hume, p. 206.8 In PHK 146 (LJ 2 107–8) Berkeley seems to suggest that God is not the causal source of our

sensations, but only of most of them; this leaves open the possibility that our wills are the causesof those sensations involved in our own voluntary physical movements. However, Berkeley doesnot develop this suggestion. It is possible that Berkeley simply means to allow for the fact thatmental images are causally dependent on our wills.



words, my volition seems more like an occasional cause in this case.9 Ofcourse, as Berkeley says, ‘’tis we that will [the movements]’; it is indeed wewho do the willing. But what is at issue between Malebranche and Berkeley iswhether this willing is causally efficacious, and Berkeley, like Malebranche, isdeeply committed to the view that it is not.In fairness to Berkeley, it must be noted that immaterialism leaves the will

sovereign in one sphere; the thesis that bodies are collections of ideas exerts nopressure towards an occasionalist account of imagination. Consistently withhis immaterialism, Berkeley can say that we are causally active in imaginingthe Eiffel Tower or pink elephants; not merely do we perform volitions, butthese volitions are causally efficacious. Unlike sensory ideas, ideas of imagin-ation are not causally dependent on the will of another spirit, God; they arecausally dependent on our own wills. It may seem, then, that in imaginationBerkeley has found a stronghold where he can take his stand against unquali-fied occasionalism; here, it seems, he has found a way of denying somethingthat Malebranche would accept. But the appearance is misleading. For, as wehave seen, there is another force in Berkeley’s philosophy which pushes himtowards occasionalism, and this does not discriminate between the cases ofvoluntary physical movement and imagination. According to Berkeley, it is byexperience that we find that our ideas of imagination appear when we willthem (PHK 28, LJ 2 53). But if this means, as I think it does, that theconnection between volition and upshot can be known only inductively, itseems that, for Berkeley, it cannot be genuinely causal.Berkeley is thus in great difficulties on the subject of volition. Officially, he is

committed to the position that finite spirits are causally active; unofficially, he issubject to pressures which make it difficult for him to maintain this anti-Malebranchian stance.Why, then, does Berkeley reviseMalebranche’s unquali-fied occasionalism in away that seems so unsatisfactory? It is of course temptingto say that the answer, or part of the answer, is to be found in Berkeley’s concernwith the defence of common sense; Berkeley ‘sides in all things with the Mob’(PC 405, LJ 1 51), and the mob believe that they move their legs themselves.But it is difficult to know what role common sense really plays in Berkeley’sphilosophy, and how much weight he attaches to it. In any case, the defenceof common sense cannot be the whole answer: it cannot explain Berkeley’sdifferential treatment of bodies and spirits with respect to causality, forcommon sense presumably tells us that bodies are just as much causally activeas our wills. It is necessary, then, to look for other reasons which Berkeley mayhave for attributing causal powers to finite spirits but not to bodies. Let us beginby looking in the direction of theology.

9 C.C.W. Taylor, ‘Action and Inaction in Berkeley’, in J. Foster and H. Robinson (eds.), Essayson Berkeley: A Tercentennial Celebration (Oxford: Clarendon Press, 1985), p. 222.



I I I

Berkeley the theologian would surely insist that it is important not to putbodies and finite spirits on the same causal footing. There are good theologicalreasons for trying to show that bodies are not endowed with genuine causalpowers; by contrast, there are no such reasons for trying to establish the samethesis with regard to finite spirits. Indeed, Berkeley would want to go furtherthan this; he would want to insist that good theology requires us to conceive ofour minds as genuine causes. These theological ideas are not very intuitivetoday, and they therefore need to be explained.

First of all, we should notice an important area of agreement betweenBerkeley and Malebranche which has only recently begun to receive properattention. In an early entry in the Commentaries Berkeley deplores the ‘rise ofidolatry’ (PC 17, LJ 1 10), and the discrediting of idolatry remained a majormotive in philosophy for Berkeley as for Malebranche.10 For both philoso-phers, the Aristotelian philosophy of nature was vitiated by a dangerous andfundamental error; indeed, in a well-known chapter of the Search, Malebranchedescribes it as ‘the most dangerous error of the philosophy of the ancients’(SAT 6.2.3, OCM II 309; LO 446). This error is the belief that nature is a realmof secondary causes, or entities endowed with genuine causal powers andforces. Such a conception of nature encourages idolatry by promoting the beliefthat bodies are endowed with godlike properties which make them worthy ofworship; as Malebranche quaintly puts it, it encourages us to pay sovereignhonour to leeks and onions (SAT 6.2.3, OCM II 311; LO 447). This view ofnature might be understandable, and indeed is only to be expected, in a paganphilosopher such as Aristotle, but it is inexcusable in Christian philosopherswho are informed by the Scriptures of God’s immediate operations and of thetotal and direct dependence of all things on him. It is thus important to showthat this ‘nature this philosopher [Aristotle] has established is a pure chimera’(SAT, Elucidation XV, OCM III; LO 668). Berkeley follows Malebranche veryclosely here; he too maintains that this conception of nature is a ‘vain chimera’:

But you will say, hath Nature no share in the production of natural things, andmust they be all ascribed to the immediate and sole operation of God? I answer, ifby Nature is meant only the visible series of effects, or sensations imprinted onour minds according to certain fixed and general laws, then it is plain that Naturetaken in this sense cannot produce anything at all. But if by Nature is meant somebeing distinct from God, as well as from the Laws of Nature, and things perceivedby sense, I must confess that word is to me an empty sound, without an

10 On the concern with idolatry in Malebranche and Berkeley, see McCracken, Malebrancheand British Philosophy, pp. 211–17. For a remarkable use of the ‘image of God doctrine’ whichseems close in spirit to Berkeley, see Leibniz, Principles of Nature and of Grace 14, G VI 60; AG211.



intelligible meaning annexed to it. Nature in this sense is a vain chimera intro-duced by those heathens, who had not just notions of the omnipresence andinfinite perfection of God. But it is more unaccountable that it should be receivedamong Christians professing belief in the Holy Scriptures, which constantlyascribe those effects to the immediate hand of God, that heathen philosophersare wont to impute to Nature.

(PHK 150, LJ 2 109–10)

Berkeley even follows Malebranche to the extent of quoting scriptural passagesas evidence of the ‘immediate and sole operation of God’.

To ascribe causal powers to bodies, and thus to treat them as endowed withgod-like properties, is, then, a thesis which encourages idolatry. By contrast, forBerkeley, no idolatry is involved in ascribing such god-like powers to humanminds or finite spirits. Far from being impious, such an attitude is actuallyrequired by the Christian religion, for according to Genesis, man is made in theimage of God. Edward Craig has shown that the Genesis doctrine, as applied tohuman minds, plays a central role in seventeenth-century philosophy; indeed,it motivates much that would be otherwise obscure.11 In this respect Berkeley isvery much of his age; he too gives a prominent place in his philosophy to thedoctrine that the human mind is made in the image of God. In the Dialogues,for instance, Philonous remarks that ‘I have . . . though not an inactive idea, yetin myself some sort of an active thinking image of the Deity’ (DHP III, LJ 2232). The Genesis text also seems to lie behind a remarkable passage in Siris:

In the human body the mind orders and moves the limbs; but the animal spirit issupposed the immediate physical cause of their motion. So likewise in themundane system, a mind presides: but the immediate mechanical, or instrumen-tal cause that moves or animates all its parts, is the pure elementary fire or spiritof the world.

(Siris 161, LJ 5 85)

Berkeley seems to be suggesting that our likeness to God is exemplified in theanalogy between the mind’s power over its body and God’s dominion over theworld. Like Descartes, Berkeley may well believe that ‘it is above all in virtue ofthe will that I understand myself to bear in some way the image and likeness ofGod’ (Meditations IV, AT VII 57; CSM II 40).12

Here it is instructive to compare Berkeley’s positionwith that ofMalebrancheto whom hemay well be replying. Malebranche, like other seventeenth-centuryphilosophers, pays his respects to the Genesis doctrine; he even claims toaccommodate it in his own philosophy. In presenting his case for vision in

11 E.J. Craig, The Mind of God and the Works of Man (Oxford: Clarendon Press, 1987), esp.ch. 1.

12 It should be pointed out that Descartes makes this claim in the context of his discussion ofthe role of the will in assent.



God, Malebranche claims that our minds are united to God (specifically, theWord), and for Malebranche, ‘it is through this union of our mind with theWord of God . . . that we aremade in the image and likeness of God’ (SAT 3.2.6,OCM I 446; LO 235). But Berkeley could plausibly claim that Malebranchecannot really do justice to the Genesis doctrine. All the emphasis in Male-branche’s philosophy falls on the disanalogy between human minds and God.For Malebranche, as we have seen, God is not merely omnipotent; he is the soletrue cause; finite minds, by contrast, including of course the human mind, arecausally impotent. Moreover, as Malebranche himself insists, the doctrine ofvision in God reaches parallel conclusions in the epistemological sphere (SAT6.2.3, OCM II 315; LO 449). According to the doctrine of vision in God, Godalone is the locus of ideas, and these ideas are necessary for all genuineknowledge of the world; the human mind is thus incapable of achieving suchknowledge unless it is related to the ideas in God. In the metaphorical languageof which Malebranche is so fond, our mind is in a state of darkness unless it isilluminated by divine light. Thus the mind is not only causally impotent; byitself, it is also as it were cognitively impotent. Berkeley would be justified inclaiming that, despite Malebranche’s lip service to the Genesis text, his philoso-phy can give no real sense to the doctrine that the human mind is made in theimage of God.

From Berkeley’s perspective, then, Malebranche had mounted a powerfulattack on idolatrous attitudes towards physical nature, but he had paid too higha price for his success; he had undermined idolatry at the cost of compromisingthe Genesis doctrine that themind is made in the image of God. For Berkeley, itwas important to re-establish the asymmetry between bodies and finite spiritsfor which Scripture provided warrant. For theological purposes it was essentialto discover an argument which drove a wedge between bodies and finite spiritswith regard to causality. Such an argument should at least meet the desider-atum of showing that bodies are causally powerless while having no suchimplications for the status of finite spirits. Now Berkeley’s immaterialismseems to supply him with just such an argument. Bodies are collections ofideas, and ideas are ‘visibly inert, there is nothing of power or agency includedin them’, so bodies are powerless and hence not causes (PHK 25, LJ 2 51).13

Possibly Berkeley himself became dissatisfied with this argument; certainly, asBennett says, the second premise is ‘tremendously unclear’.14 Moreover, theargument seems to involve an instance of the fallacy of composition: from thefact that each individual idea is inactive, it does not follow that a collection ofideas is inactive. But whether Berkeley thought the argument was actuallyflawed or merely psychologically ineffective, he supplemented it with another,more Malebranchian argument for the thesis that bodies are causally

13 See Bennett, Locke, Berkeley, Hume, p. 199.14 Bennett, Locke, Berkeley, Hume, p. 199.



powerless—one that did not depend on immaterialism. Unfortunately, thissecond argument, from the non-inductive basis of our knowledge of genuinecausal relations, is not well-suited for Berkeley’s purposes, for as we have seen,it tends to undermine the very asymmetry between bodies and finite spiritswhich, for theological reasons, Berkeley is anxious to uphold.

IV

Berkeley also has more purely philosophical reasons for departing fromoccasionalism in the way he does, and these take us to the heart of hisphilosophical quarrel with Malebranche. So far we have tended to emphasizeBerkeley’s affinities with Malebranche at the expense of his links with Locke,but we can no longer afford to ignore the Lockean side of Berkeley’s inherit-ance. For Berkeley is committed to certain fundamental Lockean assumptionsabout concepts, and these assumptions are important for understanding hisdeparture from unqualified occasionalism. In the first place, Berkeley followsLocke in regarding concepts as psychological items for which it is appropriateto seek a causal explanation; with respect to any concept, it always makes senseto ask how we acquired it, or more crudely, where it came from. So muchBerkeley has in common with both Locke and Descartes, but he also makes themore distinctively Lockean assumption that the source of our concepts lies inexperience. It is this latter claim, in particular, which helps us to understandhis philosophical reasons for insisting on the causal activity of our mind.Consider, then, our concept of causality from a Berkeleian perspective.

Berkeley cannot strictly say that we have an idea of it, for ideas, for Berkeley,are images, and we can form no image of causal power. But we do possess anotion of causality, and this notion is not only a psychological possession; ithas its source wholly within our experience of volition. The concept ofcausality cannot be abstracted from volition, and has no application beyondit. It is on the basis of our experience of volition that we form the notion of abeing with unlimited causal power; when such a concept is suitably augmentedto include other perfections, we have the notion of God. Berkeley evenprovides an argument to show that our mind is the image of God, or rather,that our notion of God is made in the image of our mind:

taking the word idea in a large sense, my soul may be said to furnish me with anidea, that is, an image or likeness of God, though indeed extremely inadequate. Forall the notion I have of God, is obtained by reflecting on my own soul, heighteningits powers, and removing its imperfections. I have therefore, though not an inactiveidea, yet in my self some sort of an active thinking image of the Deity.

(DHP III, LJ 2 321–2)



Thus Berkeley is committed to the thesis that unless we experience causality inourselves, we should have no concept of causality.

Berkeley’s position is vulnerable on several grounds. Suppose that, for thesake of argument, one were to accept the empiricist programme of finding thesource of concepts within our own experience. It might still be claimed that anempiricist account of our concept of causality is consistent with the occasion-alist doctrine that our minds are causally impotent. Consider, by way ofanalogy, the case of our concept of infinity. Conceptual empiricists such asLocke and Berkeley typically claim that we acquire this concept from experi-ence by suitably processing our concept of the finite. In the same way aconceptual empiricist could claim that we acquire the concept of genuinecausality from experience by suitably processing the concept of causal impo-tence which we acquire from both sensation and introspection. One might alsoseek to criticize Berkeley from a more external standpoint by charging that hisderivation of the concept of causality from experience is circular. We aresupposed to acquire this concept by introspecting and noticing that ourmind exercises genuine causal activity in volition. But in order to notice thisit seems that we must already be in possession of the concept of causality.

Let us now consider two distinctive criticisms that Malebranche wouldmake of Berkeley’s position. In the first place, Malebranche would insist thatwe must distinguish between true and false ideas of causality. If what is inquestion is the idea of power, then Malebranche would claim that, strictlyspeaking, we have no idea of this at all; for Malebranche, the term ‘power’ isempty of all real content. The true idea of causality is the idea of a necessaryconnection between two events such that if one occurs, the other must occur.15

Thus any serious philosophical enquiry concerning the concept of causalitymust be addressed to the concept of necessary connection.

This clarification of the concept of causality is only a preliminary move,however. For Malebranche has a deep reply to Berkeley which challenges hisbasic assumption about concepts. For Malebranche, in contrast to Descartesand Locke, the empiricist programme does not simply give a wrong answer toa legitimate question about the origin of ideas; it goes wrong in a morefundamental way. The whole project of seeking to explain the origin ofconcepts is misguided in principle, for it involves something like a categorymistake; it makes the assumption that concepts are psychological entities forwhich it is appropriate to seek a causal explanation. Malebranche may some-times write as if he shares this assumption, but it forms no part of hisconsidered position. Strictly speaking, for Malebranche, concepts are notpsychological but, as we might say, abstract logical entities; such entitieshave a locus—God—but it makes no sense to suppose that they have a causal

15 I owe this formulation to McCracken, Malebranche and British Philosophy, p. 99.



source. Thus to Berkeley’s challenge: ‘Where could our notion of causalitycome from if not from experience?’ Malebranche would reply: ‘It does notcome from anywhere; it’s not a psychological possession at all.’ This does notmean that Malebranche would similarly dismiss the question of how it ispossible for us to think of causality; on the contrary, he would regard thisquestion as legitimate, and he would seek to answer it in terms of our beingrelated to concepts (ideas) in God. Thus, in response to this question Male-branche would invoke his famous doctrine of vision in God. Berkeley of courseinsisted, and insisted rightly, that he rejected this doctrine, at least as it ispresented in The Search After Truth.16

We have seen, then, that Berkeley found it important for theological reasonsto maintain the asymmetry between bodies and finite spirits with regard tocausality. Sound theology requires us to attack the idolatrous philosophy ofnature which is the legacy of the pagan Aristotle; to this extent Berkeley agreeswith Malebranche. But sound theology also requires us to uphold the Genesisdoctrine that the human mind is made in the image of God, and in Berkeley’seyes this doctrine is dangerously compromised by Malebranche’s philosophy.As we have seen, Berkeley also has more purely philosophical reasons fordeparting from a strictly occasionalist position with regard to finite spirits. Butunfortunately, in attacking the roots of idolatry Berkeley also helped himself tothe Malebranchian argument which tended to undermine the causal asym-metry between bodies and finite spirits which he sought to defend. Moreover,Berkeley seems not to have noticed that even his immaterialism when thoughtthrough tended in an occasionalist direction. We can see why Berkeley foundit necessary to depart from Malebranche’s unqualified occasionalism, but wecannot defend his departures on grounds of philosophical consistency. Berke-ley’s position on causality is, at bottom, incoherent. Even in his publishedwritings Berkeley remains more of an occasionalist than he is willing to allow.

16 See chapter 15 in this volume for a discussion of the relationship between Berkeley’s theoryof perception and Malebranche’s later version of the doctrine of vision in God.



17

Hume, Malebranche, and theLast Occult Quality

In recent years philosophers have become increasingly aware that the periodbetween Descartes and Hume was one of intense and imaginative enquiry intothe nature of causality.1 Despite his boast of beginning again on new founda-tions, Descartes did no serious rethinking about causal relations or their rolewithin the newmathematical physics; rather, he uncritically adopted Scholasticassumptions and principles which had no real place in his own, very differentconceptual framework. It was left to Descartes’ successors to complete theCartesian revolution in this area of philosophy by making the clean breakwith Scholasticism which Descartes had failed to achieve. In particular, Male-branche’s occasionalism is no longer seen as a clumsy ad hoc solution to themind–body problem; it is now viewed, correctly, as a principled thesis whichhas a crucial place in the development of thought about causality in general.Thus, the Humean theory of causality did not spring fully armed into the worldlike Athena from the head of Zeus; its emergence was anticipated in crucialrespects by Malebranche. Indeed, it is not too much to say that a consensus hasbegun to emerge in this area. Malebranche’s occasionalism represents aninteresting, if unstable, halfway house position on the road to Hume.2

In this essay I wish to challenge this emerging consensus by outliningan alternative way of thinking about the relationship between Malebrancheand Hume. According to the picture that I will sketch, Malebranche is in some

1 Earlier versions of this essay were read to departmental colloquia at the University ofCalifornia, Irvine; the University of Virginia; Cornell University; and to the Eastern PennsylvaniaPhilosophy Association Conference at Bloomsburg University. I am grateful to members of theaudiences on each occasion for helpful comments. I should also like to thank Justin Broackes forhis editorial suggestions.

2 Elements of this emerging consensus are found in C.J. McCracken,Malebranche and BritishPhilosophy (Oxford: Clarendon Press, 1983), ch. 7; S. Nadler, ‘Malebranche on Causation’, inNadler (ed.), The Cambridge Companion to Malebranche, pp. 133–6; N. Jolley, The Light of theSoul: Theories of Ideas in Leibniz, Malebranche, and Descartes (Oxford: Clarendon Press), ch. 6.The expression ‘halfway house’ is my own (Light of the Soul, p. 103), but it also seems to capturethe views of McCracken and Nadler.


respects the more progressive and interesting of the two philosophers; indeed,Malebranche grasped a moral of the scientific revolution of the seventeenthcentury that eluded Hume. For one way of reading Malebranche’s doctrine ofoccasionalism credits it with the insight that there is no place for the notion ofnatural causality on the new mechanical conception of the physical world. Theconfused Scholastic notion of causality must be replaced by the more precisenotion of law; such a notion is more precise, or in Cartesian terminology, moreclear and distinct, because laws can be formulated in terms of mathematicalequations. On this view, then, as the French scholar Lévy-Bruhl has suggested,causality is simply the last of the occult qualities.3 The true heir of Malebrancheamong the British Empiricists is not so much Hume as Bertrand Russell, who inhis famous paper ‘On the Notion of Cause’ argued on somewhat similar groundsthat ‘theword “cause” is so inextricably boundupwithmisleading associations astomake its complete extrusion from the philosophical vocabulary desirable’, andfurther, that ‘the law of causality [i.e. the causal principle], I believe, like muchthat passes muster amongst philosophers is a relic of a bygone age, surviving likethe monarchy, only because it is erroneously supposed to do no harm.’4

It is perhaps wise to conclude these introductory remarks by forestallingpossible misunderstandings. In the first place, it must be conceded that, unlikeRussell, Malebranche does not jettison causality altogether, even if in some sensehe eliminates it from the created world; on the contrary, Malebranche famouslyretains the notion of causality in the case of God, and in respect of such atheologically minded philosopher, this is a rather significant qualification.I shall not deny that Malebranche’s theological commitments complicate thestory that I wish to tell, but I do claim that purely philosophical motives werepushing him in the direction of Russell. Moreover, it is no part of my intention inthis essay to suggest that the philosophical debate over causality was conclusivelywon by Russell; even today the view that the concept of causality is central toscientific explanation has distinguished advocates among philosophers. But I dowish to argue that, in the context of the new mathematical physics of the earlymodern period, there were powerful reasons for preferring a law-based model ofscientific explanation to a cause-based model. As we shall see, Malebranche wasphilosophically responsive to the sciences of his time in away thatHumewas not.

I

One of the difficulties of understanding the polemics of Hume and Male-branche on causality is that they both set their sights on different targets. In a

3 L. Lévy-Bruhl, History of Modern Philosophy in France, cited in McCracken, Malebrancheand British Philosophy, p. 102.

4 B. Russell, ‘On the Notion of Cause’, Proceedings of the Aristotelian Society 13 (1913), 1.


Hume, Malebranche, and the Last Occult Quality 255

curious passage in the Treatise Hume remarks that the ‘terms of efficacy,agency, power, force, energy, necessity, connexion, and productive quality areall nearly synonymous’ (T 1.3.14, 157). It is far from clear that this is the case.True, when we believe that the stone caused the window to break, we areinclined to say both that the stone forced the window to break, and that thewindow had to break in these circumstances. It is difficult to see that theseclaims are equivalent, or nearly equivalent. Perhaps on this issue Malebrancheis more clear-sighted than Hume, for at his best he seems to argue through adilemma. If causal claims are analysed in terms of force or energy, then theresult is so much meaningless verbiage; if, however, they are analysed in termsof necessary connection, then they are analysed in terms of a coherentconcept; the trouble is that nothing in the world falls under it.

What I have called the emerging consensus tends to focus onMalebranche’sargument for occasionalism from necessary connection, for this furnishes hismost powerful and intriguing case for the doctrine. According to Malebranchein The Search after Truth, ‘a true cause is one such that the mind perceives anecessary connection between it and its effect’ (SAT 6.2.3, OCM II 316; LO450). Now the mind does perceive a necessary connection between the will ofGod and its upshot, for God is by definition infinite, and it is a contradictionto say that an infinite being wills a state of affairs and that that state of affairsdoes not obtain. The same definition provides the basis for the negative thesisthat nothing else is a true cause. For the mind does not perceive a necessaryconnection between any events in the created world; for example, it is logicallypossible that the stationary billiard ball fails to move when struck by one inmotion. It is likewise logically possible that my arm remain at rest when I willto raise it. It follows, then, that no event in the world is a genuine cause.

In the light of this argument it is not difficult to see why Malebranchianoccasionalism has been regarded as an unsatisfactory halfway house. On thecredit side, it might be said that Malebranche had advanced at least halfwayalong the road, for he anticipates at least two Humean commitments. Not onlydoes he insist on necessary connection as the essence of causality, but likeHume he stresses that there are no objectively necessary connections betweenevents. (It may of course be objected that whether there is an objectivelynecessary connection is a function of how events are described, but that isby the way.) But it is also not difficult to see why on the debit side Malebrancheis thought to have advanced no further than halfway, and why this halfwayposition is unsatisfactory. For the argument relies on what is clearly a ration-alist commitment: causal relations are logically necessary and thus perspicu-ous to the intellect. Yet Malebranche also claims that events in the world donot satisfy this constraint on genuine causality. It may seem better philosoph-ical strategy to insist, as Hume does, on dropping the intelligibility require-ment for causal relations; true, necessary connection is indeed an ingredient ofcausality, but it needs to be reinterpreted in psychological or subjective terms.



By taking this bold step Hume is able to avoid Malebranche’s desperateremedy of taking causality out of the world and kicking it upstairs. Hume ina sense is able to accommodate the commonsense conviction that there arecausal relations in the world while telling a radically new story about thenature of the causal relation itself. Thus, while Hume owes more than wasrealized to Malebranche’s occasionalism, he retains his status as an originalthinker by virtue of his decisive break with the tradition of causal rationalism.5

Considered on its own terms Malebranche’s position has more to recom-mend it than appears at first sight. Malebranche’s insistence on the intelligi-bility of the causal relation may seem like a quaint relic of rationalism, but itis perhaps not as quaint as it appears. Even today a close cousin of Male-branche’s thesis retains its hold on our intuitions—not in connection withcausality perhaps, but rather in connection with the related concept ofexplanation. Consider the fact that explanation contexts, arguably unlikecausal contexts, are referentially opaque. Suppose, for the sake of argument,that historians make true statements of the form ‘The desire for the restor-ation of national greatness explains German support for the leader of theNazi party.’ But it would be distinctly odd and false to say: ‘The desire for therestoration of national greatness explains German support for the politicianwho most resembled Charlie Chaplin.’ Yet the phrases ‘leader of the Naziparty’ and ‘the German politician who most resembled Charlie Chaplin’ areco-referring expressions—a fact that Charlie Chaplin himself exploited togreat comic effect in The Great Dictator. While the former statement is true(let us suppose), the latter is false because it fails to satisfy an implicit demandthat we make on explanations: explanations give us insight into why the eventto be explained happened. Now it may be objected that the demand forinsight here is less than a demand for logical necessity; but it nonetheless hassomething in common with the rationalist demand for the intelligibility ofthe causal relation.A related point is that it will not do to say that in his definition of genuine

causality Malebranche has simply confused or conflated causal and logicalnecessity. Here of course there is a danger of begging the question againstMalebranche and the causal rationalists. But critics of the Malebranchianaccount of causality face a further problem. It is arguably a strength of Male-branche’s position that the only concept of necessity that is coherent is stronglogical necessity; it is the only one of which we have a clear grasp. Those whoinsist that the necessity of the causal relation is weaker than this face the task ofarticulating a coherent conception of what nomic or physical necessity mightconsist in. Even philosophers who applaud the general Humean strategy ofreinterpreting the concept of necessary connection so that it can accommodate

5 This view is endorsed by both McCracken and Nadler.



commonsensical causal judgements are unlikely to claim that Hume mademuch of a contribution to this task.

But the real weakness of the emerging consensus lies elsewhere, and it is this:it tends to be based on a controversial assumption about good philosophicalstrategy; this is the assumption that it is perverse to come up with an analysis ofthe concept of causality such that it has no application to events in the world.Surely, it may be said, philosophers should start with our unreflective causaljudgements—for example, that fires make kettles boil—and tailor their analysisof causality to them. But by making this assumption, defenders of the emergingconsensus miss the deep philosophical motivation for occasionalism—namely,to articulate an ontology that can underpin the newmathematical physics of theseventeenth century. And inMalebranche’s view, the concept of natural causal-ity is not a useful or valuable one in this context; it is a concept, rather, whichfinds its true home in the outdated framework of Scholastic metaphysics.Malebranche’s polemics against natural causality may be intemperate, but it isnot difficult to see his point here. The Scholastic universe is a world of individualsubstances ranged into natural kinds, each endowed with a distinctive set ofcausal powers; in the Cartesian system, by contrast, there are no such sub-stances. As John Cottingham has written, ‘there was simply a material plenumwhose behaviour at any givenmoment is derivable from the initial specificationsof themotions, size, shape, and arrangements of its parts.’6 In the understandingof real physical change in the system ‘what is invoked is not a causal structure ofinteracting substances and forms, but simply an initial set of divinely ordainedspecifications concerning the quantity of motion of the system as a whole.’7 InMalebranche’s proto-Russellian view, the successor concept to that of naturalcausality is the concept of law. Malebranche regularly insists that physicalexplanations invoke what he calls the laws of the communication of motionsin terms of which earlier states of the universe can be mapped on to later states.Malebranche is arguably the first philosopher for whom the concept of law inthe unambiguously descriptive sense plays an absolutely central role.

I I

The place occupied by law in Malebranche’s philosophical system has oftenbeen ignored in the past, perhaps because the textbook account of occasional-ism owed so much to Leibniz’s caricature.8 Nonetheless, all responsible

6 J. Cottingham, ‘A New Start? Cartesian Metaphysics and the Emergence of ModernPhilosophy’, in Sorell (ed.), The Rise of Modern Philosophy, p. 164.

7 Cottingham, ‘A New Start?’, p. 164.8 For a discussion of Leibniz’s critique of occasionalism, see R.S. Woolhouse, ‘Leibniz and

Occasionalism’, in R.S. Woolhouse (ed.), Metaphysics and Philosophy of Science in the



readers of Malebranche today acknowledge that the occasionalist universe is aplace governed by physical and psycho-physical laws, which, apart from themiracles recognized by Christianity, hold with strict universality. Indeed, theexistence of such laws plays a central role in Malebranche’s whole projectof theodicy, that is, of reconciling the justice of God with the existence ofthe various kinds of evil in our world. But there is some question as to howMalebranche’s insistence on the role of laws within the occasionalist system isto be understood. In particular, Malebranche’s occasionalism raises difficultquestions concerning the relationship between laws and divine causality. Suchquestions need to be addressed if we are to defend the thesis that, forMalebranche, scientific explanations are concerned with laws, not causality.It is tempting to suppose that the key to the relationship is that laws and

divine causality provide answers to distinct questions. Physical questionsconcerning the behaviour of bodies are to be answered by citing laws of nature;the behaviour of billiard balls following collision, for example, is to be explainedby deductive subsumption under a covering law (e.g., one of ‘the laws of thecommunication of motions’). But in company with his fellow-Rationalists so-called, Malebranche further believes that there is a metaphysical question to beanswered: it is the question of why there are these laws of nature. A Spinozistcan of course answer this question by saying that the laws of nature in the worldare absolutely necessary. They follow from the very nature of God conceived—let us say—under the attribute of extension. God’s nature is itself absolutelynecessary, and the attribute of extension logically fixes or determines the verylaws of physics. Such an answer to the question would be rejected by Male-branche, who agrees with Leibniz in regarding the laws of nature as contingent.Thus, like Leibniz, Malebranche believes that we need to be able to explain whythese laws are instantiated in our world rather than other possible laws. It isonly at this stage that we appeal to God by saying: because God willed them.And then in a Leibnizian spirit we can push the questioning one stage furtherback: why did God will them? Here the answer will again be a variant on aLeibnizian theme: God’s ways must honour him by virtue of their simplicity,and just these laws best satisfy this criterion. On thismodel, then, laws of natureand divine causality answer physical and metaphysical questions respectively.Such an approach to understanding the relationship between laws and

divine causality has obvious attractions. Not only does it sharply demarcatethe spheres of laws and causality, but it also does justice to Malebranche’sinsistence that there is a necessary connection between a true cause and itseffect. Thus on this approach God’s volitions clearly satisfy the definition oftrue causality: it is a necessary truth that if God wills the laws of nature, thelaws of nature obtain. The interpretation also has the merit of doing justice to

Seventeenth and Eighteenth Centuries, pp. 165–83; repr. in V. Chappell (ed.), Gottfried WilhelmLeibniz, Part II (New York and London: Garland, 1992), pp. 435–53.



Malebranche’s insistence that divine causality is not to be invoked in theexplanation of physical phenomena.

If one asks me, for example, how it comes about that a piece of linen dries whenone exposes it to the fire, I should not be a philosopher [i.e. a natural philosopheror scientist] if I reply that God wills it; for one knows well enough that everythingwhich happens, happens because God wills it.

(Conversations chrétiennes III, OCM IV 77)

The solution is attractive, but unfortunately it cannot be right, for it runs intotrouble from other central components of Malebranche’s teaching about laws.On the interpretation I have sketched, the laws of nature that obtain in ourworld are the upshots of divine volitions; they are simply the effects of God’scausally efficacious will, and are thus purely passive, as it were. But Male-branche regularly insists that the laws of nature are efficacious; they arethemselves active. In The Search after Truth, for instance, Malebranche writesthat ‘[God] also willed certain laws according to which motion is communi-cated upon the collision of bodies, and because these laws are efficacious theyact whereas bodies cannot act’ (SAT 6.2.3, OCM II 314; LO 449). Thus anyinterpretation of the laws of nature and their relationship to divine causalitymust be able to give some account of how laws can be efficacious.

The doctrine of efficacious laws poses two troublesome problems of con-sistency. In the first place, it may seem that the doctrine is in conflict withthe central teachings of occasionalism. In other words, it may seem that thedoctrine of efficacious laws smuggles genuine causality into the world by theback door; it is laws, not particular bodies or events, that are endowed withgenuine causality, and if such laws are regarded as structural features of theworld, then there are creatures that are genuine causes. Such a thesis wouldclearly be contrary to the occasionalist tenet that God is the one true cause.I have addressed this problem elsewhere by suggesting that, for Malebranche,laws are not in fact features of the created world; they are not ontologicallydistinct from God himself.9 Malebranche does indeed subscribe to a volition/upshot model of divine causality, but laws of nature belong on the volition, notthe upshot, side of the divide.

For the purposes of the present paper, however, the second problem ofconsistency is more pressing. The doctrine of efficacious laws may seem to bein conflict with ascribing to Malebranche a purely law-based model of scien-tific explanation. For if the laws of nature are efficacious, it seems they havecausal powers, and if this is so, then insofar as scientific explanation appeals tolaws of nature, it also appeals to genuine causes. Yet, as we have seen,Malebranche wishes to insist that scientific explanation makes no appeal todivine volition, and thus no appeal to genuine causality.

9 See chapter 6 in this volume.



It is natural to adopt the same strategy for solving this second problem as forsolving the first—that is, by making a distinction with regard to divine voli-tions. In order to answer the first charge of inconsistency, it was the distinctionbetween volition and upshot that was crucial: laws of nature belong on thevolition side of the divide. In order to answer the second charge it is rather thedistinction between the act and the content of the divine volition that is crucial.In terms of this distinction we can explain how in one sense scientific explan-ation does indeed appeal to the divine will and in another sense it does not.Scientific explanations appeal to divine volitions in the sense that they invokethe propositional contents of these volitions; they cite, for example, the laws ofthe communication of motions where these are construed as universallyquantified propositions that support counterfactual conditionals. But in an-other sense scientific explanations involve no appeal to divine volitions; that is,they abstract entirely from God’s eternal act of willing, say, the laws of thecommunication of motions. Thus, in this way, it seems that Malebranche canconsistently hold that laws of nature are not ontologically distinct from God,while denying that scientific explanations appeal to the divine will.As propositional contents of divine general volitions, laws of nature are clearly

capable of entering into scientific explanations. But it seems that we have paid ahigh price for this result; it appears that we are now no longer able to do justice tothe claim that laws of nature are efficacious. For, as propositional contents ofdivine general volitions, laws of nature would seem to be abstract entities, andabstract entities are of the wrong ontological type to be capable of causinganything. It is true that there are places where Malebranche seems prepared toascribe causal powers to abstract entities; at least in his later writings divine ideasare said to be efficacious—they cause perceptions in finite minds. And ideas, forMalebranche, are most naturally treated as ‘third realm’ entities. But even ifMalebranche does think that, as abstract entities, propositional contents of divinevolitions are capable of possessing causal properties, that would be of noassistance to the present interpretation. For it would still be true that by appealingto laws of nature scientific explanations invoke items that are genuinely causal.All things considered, the most fruitful approach to the problem is to give up

the attempt to take the doctrine of efficacious laws strictly at face value. Indeed,Malebranche’s general theory of causality suggests that there are reasons fornot taking it in this way. For, as we have seen, for Malebranche, if A is the causeof B, then there is a necessary connection between A and B, but there is nonecessary connection between the laws of nature, considered in themselves,and particular events in the world. As Bennett says, ‘if a particular clap ofthunder were necessitated by the laws of physics, there would be thundereverywhere and always’.10 It is clear, then, that in order to satisfy the ‘necessary

10 J. Bennett, A Study of Spinoza’s Ethics (Cambridge: Cambridge University Press, 1984),p. 113.



connection’ requirement for genuine causality, we must take into account notmerely the laws of nature but the initial conditions of the universe. And whenwe do so we obtain a plausible account of where divine efficacy is to be located:what is really efficacious is neither the laws of nature taken by themselves, nor isit evenGod’s willing these laws; it is rather what wemight call God’s compoundvolition of the laws of nature and the initial conditions of the universe. On theassumption that the laws of nature are not merely probabilistic, there is indeeda necessary connection between this compound volition on God’s part andparticular events in the world. Here of course it is relevant to note that if Godwills that p, then not just p but whatever is logically implied by p is the case.

Thus, the present interpretation may not preserve the letter of the doctrine ofefficacious laws, but arguably it does preserve its spirit. It is plausible to supposethat, forMalebranche, the heart of the doctrine is that the laws of nature belong onthe volition side of the divide between divine volitions and their upshots; therefore,they are not ontologically distinct from God himself, the only causally efficaciousbeing. Such an interpretation is in line with a very natural reading of Male-branche’s theory of efficacious ideas. There Malebranche is chiefly concerned toguard against the supposition that ideas are to be numbered among items to befound in the created world. In his theory of efficacious laws of natureMalebrancheis also chiefly concerned to guard against the corresponding supposition.

We have now reached a positionwhere we can achieve a coherent perspectiveon Malebranche’s view of scientific explanation. Scientific explanations do notappeal to genuine natural or secondary causes, for there are no such entities.11

Equally, they do not appeal to genuine or divine causality; by citing the laws ofnature they invoke the propositional contents of divine general volitions andabstract entirely from the efficacy of these volitions. In its focus on laws ratherthan causality there is indeed a sense in which Malebranche’s view of scientificexplanation is a significant precursor of the Russellian view. It is true thatMalebranche’s account of scientific explanation differs from Russell’s own inimportant and to some extent predictable ways. For one thing, the concept ofcausality has not been jettisoned from philosophy altogether, as Russell recom-mended it should be; it has only beenmarginalized for the purposes of scientificexplanation. Further, for Malebranche, even scientific explanation has a theo-logical dimension to it that is alien not only to the Russellian but to all modernaccounts. According to Malebranche, when scientists seek for laws of nature,whether they realize it or not, they are attempting to discover the contents of thedivine mind. Nonetheless, there is a real sense in which Russell’s teaching is in aclear line of descent fromMalebranche’s occasionalism, despite the strangeness

11 Scientific explanations do of course cite occasional causes which Malebranche sometimescalls particular causes (see e.g. Conversations chrétiennes III, OCM 477). However, the occasionalor particular causes are simply antecedent conditions which, in conjunction with the laws ofnature, explain particular events.



of the latter doctrine. Here a familiar parallel may be helpful. No one, I think,doubts that Berkeley’s idealism, for all its theistic framework, is a significantprecursor ofmodern linguistic phenomenalism; indeed, Berkeley’s doctrine wasan inspiration for the modern theory. Malebranche’s occasionalism may nothave been an inspiration for Russell’s teaching, but it is nonetheless a significantprecursor of that teaching.

I II

In order to criticize what I call the emerging consensus, there is no need todeny that Hume adapted Malebranchian ideas to his own distinctive purposes.Commentators such as Charles McCracken have impressively documentedthe extent to which Hume is indebted to Malebranchian materials for hisnegative arguments concerning causality; they have shown, in particular, howhe takes over the Malebranchian insight that there are no objectively necessaryconnections linking events.12 Hume’s positive account of necessary connec-tion is thought to owe less to Malebranchian teachings. Curiously, however, itis by way of this account that I wish to bring out the difference in motivationbetween the two philosophers.Philosophers have not always emphasized, as much as they should, that

Hume’s whole positive approach to the issue of necessary connection is clearlymodelled on seventeenth-century discussions of secondary qualities. Hume’sambition is to do for necessary connection what his predecessors in earlymodern philosophy had done for the sensible qualities (such as colour, sound,taste, and odour). His predecessors maintained against the Scholastics thatsuch qualities are not straightforwardly manifest properties of bodies; Humebelieves that we can make progress in philosophy by extending this insight tothe case of necessary connection. But within the camp of early modernphilosophers there was no unanimity about the status of the so-called second-ary qualities; even Descartes himself seems to hesitate between regarding themas sensations, physical textures, and powers to produce ideas or sensations inthe mind. Hume’s own account of necessary connection is modelled on theview of secondary qualities that was consistently adopted only by Malebrancheand later Berkeley; for Hume, necessary connection is purely subjective. ‘Uponthe whole, necessity is something that exists in the mind, not in objects’(T 1.3.14, 165). Hume even flags his indebtedness to Malebranche by quotinghis remark—this time without acknowledgment—that ‘the mind has a greatpropensity to spread itself on external objects’ (T 1.3.14, 167; cf. SAT 1.12.5,

12 See McCracken,Malebranche and British Philosophy, pp. 257–61; cf. Nadler, ‘Malebrancheon Causation’, pp. 133–6.



OCM I 138; LO 58) when he explains the origin of the mistaken belief thatnecessary connection is an objective relation between events in the world.

Hume, then, found Malebranchian ideas helpful in framing his positiveaccount of the nature of necessary connection. But it is a telling fact that theideas in question were not taken fromMalebranche’s discussion of causality; aswe have seen, they were taken rather from his account of the status of secondaryqualities. And this serves to underline a deeper irony in the story: Hume’s wholestrategy, at least in his positive discussion of causality, is deeply unMalebran-chian. To say this is not to make the rather superficial point that Hume replacestheology with psychology; that is, it is not to say that whereasMalebranche tooknecessary connection out of the world to put it in God, Hume takes it out ofthe world to put it in themind.13 The point is quite different from that. In crudeand general terms Malebranche’s account of natural causality is through andthrough eliminativist; our belief that there are genuine natural causes (asopposed to occasional ones) is simply false. By contrast, Hume’s account ofnatural causality is through and through reductionist;14 we may be mistaken inour view of what constitutes natural causality, but we are not mistaken in ourbelief that there is such a thing in the world. Hume’s central aim is to show howsuch causality can be reduced to constant conjunction plus a subjective dispos-ition of themind to form certain expectations. It is this fundamentally reductivestrategy that is embodied in Hume’s second definition of cause (T 1.3.14, 170).

For all his brilliant innovations, Hume’s aim is in a sense a conservative one;by means of his reductive analysis he seeks to show how the truth of ourordinary, unreflective causal judgements can be preserved. And it is surelyrelevant to understanding this conservative aim that, for Hume, the notion ofcausality is one that we cannot do without; for Hume has no doubt that scienceitself is essentially concerned with the search for causes. In the Treatise Humetells the reader that he has ‘just now examin’d one of the most sublimequestions in philosophy, viz that concerning the power and efficacy of causes;where all the sciences seem so much interested’ (T 1.3.14, 156). The Enquirypoints in the same direction:

For surely, if there be any relation among objects, which it imports us to knowperfectly, it is that of cause and effect. On this are founded all our reasoningsconcerning matter of fact or existence. By means of it alone we attain anyassurance concerning objects which are removed from the present testimony ofour memory and senses. The only immediate utility of all sciences is to teach us,

13 See McCracken, Malebranche and British Philosophy, p. 263.14 The reductionist reading of Hume’s account has been challenged in J.P. Wright, The

Sceptical Realism of David Hume (Minneapolis: University of Minnesota Press, 1983), and inG. Strawson, The Secret Connexion: Causation, Realism, and David Hume (Oxford: ClarendonPress, 1989). For a cogent critique of Wright’s and Strawson’s views, see K.P. Winkler, ‘The NewHume’, Philosophical Review 100 (1991), 541–79.



how to control and regulate future events by their causes. Our thoughts andenquiries are, therefore, every moment employed about this relation.

(E 7.2, 76)

Hume, of course, is not innocent of the concept of scientific law; in the EnquiryHume remarks that ‘every part of mixed mathematics proceeds upon thesupposition that certain laws are established by nature in her operations,and abstract reasonings are employed, either to assist experience in thediscovery of these laws, or to determine their influence in particular cases’(E 1.4, 31). But nowhere does Hume see any rivalry between the search forcauses and the search for laws; there is no suggestion that the notion of causeneeds to be replaced by the notion of scientific law.Hume, then, was not well positioned to appreciate fully the strictly philo-

sophical motivation of Malebranche’s occasionalism; he failed to see howMalebranche and others sought to replace the concept of cause by the morefruitful and precise concept of law. As we have seen, Hume was indeedindebted to Malebranche’s occasionalism in its negative arguments; he under-stood and adapted to his own purposes Malebranche’s arguments to the effectthat there are no objectively necessary connections in nature. But beyond that,Malebranche’s occasionalism seemed like a metaphysical extravagance, a merecuriosity. As he famously said in the Enquiry, ‘we are got into fairy land, longere we have reached the last steps of our theory’ (E 7.1, 72).

IV

If I am right, then, Hume failed to appreciate the significance of the occasion-alist insistence on eliminating natural causality in favour of the concept of law.Why might this have been the case? One possible explanation is both specula-tive and superficial; it appeals to a change in the philosophical climate sincethe time of Malebranche. Characteristically, seventeenth-century philosophershad an inside knowledge of the scientific developments of their age; not all ofthem were scientists of the stature of Descartes and Leibniz, but many of themwere practising scientists; even Malebranche was scientifically literate enoughto be capable of engaging with Leibniz about the merits of Descartes’ laws ofmotion; the pages of The Search After Truth and the Elucidations are full ofmathematical formulae. By the time of Hume, by contrast, the intimateassociation between philosophical and scientific culture no longer existed;certainly, at the very least, we can say that Hume’s own education andexpertise were more humanistic than scientific.15

15 For an account of Hume’s education, see E.C. Mossner, The Life of David Hume, 2nd ed.(Oxford: Clarendon Press, 1980), ch. 4. Although Hume had some exposure to natural



Such claims may be greeted with some scepticism. After all, it may be said,on the title page of the Treatise Hume proclaims that it is his ambition tointroduce the experimental method into moral subjects; indeed, he evenmodels himself on the greatest of all seventeenth-century physicists when heclaims to have discovered a kind of attraction in the mental realm. I am not ofcourse forgetting or disputing such well-known facts or even playing downtheir significance for understanding Hume. But it must, I think, be concededthat nothing in the Treatise suggests a deep or inside knowledge of Newtonianmathematical physics. Everything about the book is consistent with our beingable to say of Hume what Russell said of Bergson: he was one of thosephilosophers who are too apt to take their views of science from each otherthan from science.16

A second approach to the issue would take a different and philosophicallymore interesting form. We might concede that Hume shows no signs ofappreciating what I call the deep philosophical motivation of occasionalism;that is, he shows no signs of seeing that causality is an occult quality that mustbe eliminated rather than rehabilitated. Nonetheless, we shall see that thisfailure is in no way a defect in Hume’s philosophy if we appreciate the natureof his project. Hume is not writing about causality as a metaphysician ornormative epistemologist; unlike Locke, he is not even playing the role of‘under-labourer’, seeking to clarify the assumptions and concepts of the newscience for the benefit of the educated layperson. Rather, Hume is seeking tooffer a systematically naturalistic theory of human nature; it is human nature,not inanimate physical nature, which is his real subject.17 Now human beingsmake inferences from the observed to the unobserved, and Hume wants toknow how they do it. Human beings believe that events are related by causallynecessary connections, and Hume wants to know how this belief arises in theirminds. Thus when we take Hume’s naturalistic ambitions seriously, we seethat he has good reasons for ignoring the case for eliminating causality infavour of law. The kind of considerations that impress Malebranche as ametaphysician of causality are strictly irrelevant to the Humean project.

This is a significant defence of what Hume actually does, and how oneresponds to it will depend on one’s stance on deep and vexed issues inHumean exegesis. It is possible, I think, to concede that Hume’s naturalisticproject must be taken seriously while insisting on the presence of distinct andmore traditional strands in his thought that are not fully integrated with that

philosophy at Edinburgh University, he seems to have spent more time studying courses in theArts or Humanities such as Greek, logic, and metaphysics. It is also worth noting Mossner’sremark that ‘collegiate education at Edinburgh in the early eighteenth century was more akin tothat of a modern classical high-school than a modern college’ (p. 41).

16 Russell, ‘On the Notion of Cause’, 6.17 The naturalistic side of Hume’s philosophy is strongly emphasized in B. Stroud, Hume

(London: Routledge and Kegan Paul, 1977).



project; it is not simply wilful blindness that has led commentators to offernon-naturalistic interpretations of Hume’s philosophy. Certainly there areplaces where Hume sounds as if, in opposing the occasionalists, he werewriting as one metaphysician in response to others; he is of the belief thathis thesis—that all ideas derive from impressions—places him in a position tomake an original contribution to the metaphysics of causality. Malebrancheand his fellow occasionalists have fancifully eliminated natural causality, andto that Hume responds, in terms of the empiricist theory of ideas, by offering areductionist account, which nonetheless incorporates key occasionalist in-sights. And natural causality needs to be rehabilitated in the interests ofscience; as Hume says in the Treatise, the issue of the power and efficacy ofcauses is ‘one of the most sublime questions in philosophy . . . where all thesciences seem so much interested’ (T 1.3.14, 156).In this essay I have criticized the view that Malebranche’s occasionalism is a

halfway house on the road to Hume by arguing that it distorts the motivationof the two philosophers. This may suggest that there is some larger moral to bedrawn about the perils of a ‘Whig’ approach to the history of philosophy; itmay suggest, namely, that we should avoid writing the history of philosophyfrom the standpoint of subsequent developments and awarding marks tophilosophers according to their approximation to illustrious successors. Butit is not clear that this is the right moral to be drawn; I myself have suggestedthat part of the fascination of Malebranchian occasionalism lies in its proto-Russellian themes. Indeed, as we have seen, it might be said that Malebranchehere stands in roughly the same relation to Russell as Berkeley’s idealism doesto modern linguistic phenomenalism. Perhaps the important point is not thatwe should avoid writing the history of philosophy in the light of illustrioussuccessors, but rather that we should be clear about who the successors trulyare; and for this, attention to philosophical motivation is essential. But thecomparison with Russell does suggest a warning. Let us come back to ourearlier worry: whereas Russell wants to extirpate the term ‘cause’ from thephilosophical vocabulary, Malebranche wants to retain the notion in the caseof God. The danger of the comparison with Russell is that we shall be led toassume that the total Malebranchian position lacks philosophical integrity,and that only theological motives prevented him from going as far as Russellhimself. We may perhaps say, with due caution, that Malebranche’s occasion-alism is a halfway house on the road to Russell, but it would be wrong to inferfrom this that the house is philosophically unstable.



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Index

accidents 155–6Adams, R.M. 84, 193Al-Ghazali 4Alquie, F., 49n, 52–3, 74, 103–4, 236animals 64–7, 77–8, 209–10, 214, 223–8Aristotle 13–14, 17, 74, 248, 253Arnauld, A. 5, 26, 58, 83–5, 86, 92–3, 95,

96, 106, 135, 138, 174, 175, 177atemporality 178–80Augustine, St 33, 44, 69, 114autarkeia 169, 173, 178Ayer, A.J. 10Ayers, M.R. 199–200

Bayle, P. 5, 139–40beast-machine doctrine 64, 66, 78,

223, 228Bennett, J. 32, 57n, 101, 221, 245–6,

250, 261Berkeley, G. 187, 189, 198on abstract ideas 9, 199, 231, 237–41on causality 242, 244–5, 247, 251idealism of 10, 184, 186, 189, 267on idolatry 248–50immaterialism of 246–7, 250on material substance 234–5and occasionalism 6, 230, 242, 247phenomenalism of 184, 241on vision in God 229–30on volition 245–7, 251

body 21, 23, 33, 39, 40, 41, 62essence of 22mind better known than 21, 23scientia of 18

Bourguet, L. 177Boyle, R. 144–5Brentano, F. 57Broad, C.D. 117–18Brykman, G. 230

Causal Adequacy Principle 31, 33–5, 36, 42causality 3–7, 99, 104, 168, 242, 244, 247,

250–3, 254–8, 259–60, 261–2, 265,266, 267

authorial 172, 175, 178divine 93, 96, 175, 177, 260, 262final 166immanent 151, 153, 157, 158, 159intersubstantial 153, 154, 157, 175intrasubstantial 157, 160, 161, 162, 163,

164, 167and necessary connection 101, 153, 230,

236, 243, 252, 256transeunt 151 see also occasionalism

causal likeness principle 29Clarke, S. 144–5Collins, A. 214, 223continuous creation 4, 40, 97–8, 157,

158, 175Cottingham, J. 16–17, 31, 258Couturat, L. 2, 151, 192Cover, J. 176, 178Craig, E. 153, 249Cudworth, R. 99n

Des Bosses, B. 191, 192Descartes, R.on animals 8, 64, 77–8, 210, 212, 223–4Causal Adequacy Principle of 4, 31,

35, 36, 42and causal likeness principle 29and clear and distinct ideas 16, 17, 23, 79and cognitio 20–1, 22, 24dualism of 4, 26, 194, 213, 219on eternal truths 14–15, 201on innate ideas 40, 109–10, 210–12interactionism of 28, 39, 42, 137on mind as better known than body 12,

18, 19, 20–1, 23, 27, 80and scientia 13–14, 15–19, 20–1, 22,

23–7, 90, 200on secondary qualities 36–7, 62on sensation 8, 41–2, 75–6theory of ideas of 7, 34–5, 108on thought as essence of mind 25, 71,

217, 220on true and immutable natures 25and wax meditation 22–3


determinism 26–7De Volder, B. 147–8, 149, 171dispositional properties 26, 37, 110,

115–18, 131, 146, 161–2divine illumination 43–6, 52, 56, 73, 127;

see also vision in God

Epicurus 89, 215essence 25, 70, 141–2, 173, 221–2

nominal 222real 222

eternal truths 14–15, 200–4Euclid 25evil 93, 259

forceactive 197derivative 148, 149primitive 148, 197–8

Foucher, S. 114freedom 26, 86, 127Furth, M. 183, 189–191

Gassendi, P. 19–20, 21–3, 26, 80, 85, 87Gaukroger, S. 17geometry 18, 25, 27, 79, 81, 83, 85,

127, 185Geulincx, A. 243God 4, 15, 23, 24–5, 30, 31, 46, 47, 53, 55,

66, 67, 125, 129–30, 132, 157, 246,248–9

as absolutely perfect being 124action on creatures of 151, 152, 155, 156analogy with author 173, 176benevolence of 197and continuous creation 4, 40, 97–8,158, 163, 175

as creator 32, 122–3, 158, 160, 163, 166essence of 236–7general volitions of 93, 96, 97, 98,101–2, 261

glory of 148idea of 205ideas in 44–5, 49, 50, 52, 53, 54, 59–60,102–3, 162, 231, 232–3, 234, 235, 236,238–9, 240, 241

infinity of 256justice of 67, 93, 259mirror of 180–1omnipotence of 129, 151, 225, 236,243, 250

omniscience of 97, 129as one true cause 92, 99, 135, 168, 242,250, 260

particular volitions of 95, 97–8as person 54as region of ideas 54, 114, 230, 236, 253simplicity of 27, 201transcendence of 163–4will of 54, 94, 247, 260, 261

Gueroult, M. 55–6, 72

Hacking, I. 10–11, 14Hampshire, S. 245happiness 124, 125–6, 131–4Hart, H.L.A. 245Hobbes, T. 31Hume, D.and causality 3, 4, 29, 168, 254–5and constant conjunction 138–9, 264and laws of nature 265and necessary connection 256, 263–4and occasionalism 265–7and secondary qualities 263–4on volitions 245

Husserl, E. 57, 74

ideasabstract 9–10, 199–200, 201, 203,205–6, 208, 209–10, 212, 223–5, 229,237–41

as abstract entities 44, 53, 58, 59, 63clear and distinct 16, 17, 23, 79, 194, 209as dispositions 115, 116, 162efficacious 49–54, 72, 102–3, 232–5eternity of 45, 102formal reality of 34–5, 40, 42, 203, 204infinity of 87, 102innate 44–5, 70, 105, 106–7, 108–14,116, 117, 118, 119, 120, 121, 127,199–200, 205, 210–11

as logical concepts 59, 76, 231–2necessity of 45, 87, 102objective reality of 34–5, 38–40, 41, 42,62, 203, 204

obscure and confused 75, 209imagination 44, 70, 246, 247intellectin broad sense 44pure 43, 44–7, 48–9, 56, 103

intentionalitycontent theory 58

276 Index


as mark of the mental 8, 68object theory 58–9, 68

John, St 44, 65Julius Caesar 162–3

Kant, I. 12Kenny, A. 30, 32–3knowledgea priori 45, 79–82, 85, 86, 88, 127, 245through consciousness 12, 79–80, 88through ideas 79, 88incorrigible 87see also scientia

laws of natureand causal powers 136, 139, 142as contingent 145, 259descriptive sense 144–5efficacious 5, 93–4, 99–100, 103–4,260–1

prescriptive sense 144–5and regularities 140search for 265

Leibniz, G.W.on appetition 164–7, 180–1on bodies as aggregates of monads 183,188, 190, 191–2, 194

on complete concepts 162concept-containment theory of truthof 2, 122, 151–2

and Daseinstreben doctrine 166–7on divine concurrence 128, 157, 175idealism of 184on influx 153–7, 168on innate ideas 105, 113–14, 116, 117,118, 119, 120, 121

and Law of Continuity 159on laws of nature 120, 140–1, 142–5logicist interpretation of 2, 122on materia prima 195on miracles 119, 135, 139–40, 143on monads 149, 165, 170, 174, 176–7,179–82, 188–90, 191–2, 193, 194, 195,196, 197

on occult qualities 146–7and phenomenalism 183–6, 189–91,192, 195, 196, 197–8

on possible worlds 123–4, 133,160–3, 166

and pre-established harmony 120–1,149–50

and Principle of the Best 145, 185–6and Principle of Intelligibility 141and Principle of Substantial Causality 149and Principle of Sufficient

Reason 176, 182and scepticism 188–9theodicy of 121, 122, 123, 196on unconscious perceptions 119,

120, 131on vision in God 121

Levy-Bruhl, L. 5, 136, 139, 255Locke, J.on abstract ideas 9, 199–200, 201, 203,

205–6, 208, 209–10, 212, 223–5,237–8

on animals 209–10, 223–8on immortality 215–17, 227–8on innate ideas 105, 205on real and nominal essences 222and tabula rasa 105, 116on thesis that mind always thinks 9, 215,

217–20on thinking-matter hypothesis 141, 221,

225–6, 227, 228Loeb, L. 28, 29, 32–3, 151, 157, 159,

183, 190–3

Mackie, J.L. 2, 207–8, 213Malebranche, N.and adverbial theory of sensations 61, 63,

75–7on animals 8, 64–7, 77–8anti-psychologism of 79, 107, 111on efficacious ideas 49–56, 102–3,

232–4, 235, 236–7, 261on efficacious laws 5, 93–4, 99, 100,

103–4, 260–1on general volitions 93, 96–8,

101–2, 261on idolatry 248, 250on intelligible extension 46, 118–19, 233occasionalism of 2, 4–5, 92–3, 99–100,

137, 236, 243, 247on particular volitions 95, 97–8on pure perceptions 72, 73, 109and rainbow-coloured soul 61, 63, 74–5on sentiments 45–7, 51, 55, 59, 64, 233theodicy of 67, 121, 122–3

Index 277


Malebranche, N. (cont.)on vision in God 1–2, 231–2, 234, 240,250, 253

Mates, B. 114, 117, 160–3McCracken, C. 263McDonough, J. 6McRae, R. 196mind

better known than body 12, 18–19,20–1, 23, 80

‘dustbin theory of ’ 7essence of 25, 70–1, 85, 220–22freedom of 86as image of God 155, 249–50, 253immateriality of 87, 214, 215, 216,218–19, 223, 226–8

immortality of 86, 88–90, 215–17,219, 226–8

interaction with body 28, 29, 33, 41, 137no idea of 79, 85not a light to itself 45, 69, 70, 79, 233perfections of 126, 128, 129scientia of 13, 18–27, 85, 90spirituality of 86–9union with body 41, 60union with God 51, 60, 102, 233, 250

miracles 92, 119–20, 143definition of 139–40

modes 32–3, 39, 71momentum, conservation of 137–8monads 149, 165, 170, 174, 176–7,

179–82, 186, 188, 189–92, 193,194, 195, 196, 197–8

atemporality of 178–80More, H. 223

Nadler, S. 5, 76, 93–7, 104, 123necessary truths 15, 45, 71Newton, Sir I. 18, 116Nolan, L. 7, 12–13, 15–18, 37n

occasionalism 2, 4–5, 92–3, 99, 100,135–41, 142, 143–4, 145, 146–8, 150,242–3, 246–7, 256–7, 259

Ockham’s razor 77O’Leary-Hawthorne, J. 176, 178

Parkinson, G.H.R. 184–6Parsimony, Principle of 66–7Pascal, B. 18Phemister, P. 13

phenomenalism 10, 183–6, 189–91, 192,195, 196, 197–8, 241, 263, 267

Plato 89, 114Platonism 87, 161, 201, 204

qualitiesoccult 146–7primary 37, 65, 195, 233secondary 36–7, 51, 61–2, 195, 233,263–4

Radner, D. 30, 64–5Radner, M. 64–5Regis, P.-S. 88, 102, 233Reid, T. 1Robinet, A. 49–50Rorty, R. 67Russell, B. 2, 10, 136, 151, 255, 262–3, 267Rutherford, D. 140–1

Schmaltz, T. 72, 85, 87–8Scholastics 3, 116, 146, 153, 154, 155, 199,

254, 258scientia 13–14, 15–19, 20–1, 22, 23–7, 79,

83, 85, 90, 200sensations 8, 41–2, 45, 46, 51, 65, 66, 71adverbial theory of 61, 63, 75–7confused 8, 45, 75not intentional 59, 61, 78

sense-perception 7–8, 33, 34, 40, 51, 58,77, 195, 231

Shakespeare, W. 172–3, 175Sleigh, R.C. 138, 174soul see mindSpinoza, B. 32, 54, 57, 133, 141, 145, 148,

165, 169–71, 173–4, 177–8, 181Stillingfleet, E. 206, 207, 223, 225–8Suarez, F. 145, 154, 155substancecausal self-sufficiency of 129, 130, 169,170, 172, 173, 174, 176, 178, 182

corporeal 190, 191created 151–2, 156, 171, 177–8definition of 171–2extended 39finite 32, 33, 113, 159idea of 205, 206–9independence of 32individual 162infinite 32–3material 234

278 Index


as mirror of God 128, 129, 181simple 169, 173, 185–6, 189, 190–2thinking 33, 34, 44, 70see also monads

Taylor, C.C.W. 246–7theodicy 67, 93, 121–3thinking-matter hypothesis 221, 225–8

understanding see intellect

Vailati, E. 145Vendler, Z. 172

vision in God 1, 2, 231–2, 234, 240, 250,253; see also divine illumination

volition 245–6, 251–2, 260, 261; see alsowill

volition/upshot 100–2, 246, 260

Whipple, J. 7, 12–13, 15–18will 42, 44, 49, 54, 70, 72, 94, 100,

101, 103, 138, 243, 246, 247, 249,256, 260, 261; see also volition;volition/upshot

Wilson, M. 21–3, 38, 197Woolhouse, R. 137

Index 279


nicholas jolley - causality and mind [2014][a]

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