Barbara C. Scholz

In its everyday use, the word ‘innate’ sayssomething about origins. If we claim someattribute is innate (or inborn, or inherit-

ed), we are saying that it originates internally— its cause is located inside the organism.What is not innate originates in the externalworld. When behaviours or capacities tobehave are innate, the word ‘instinct’ isapplied. If a behaviour or capacity is notinstinctive, then its origin must be outsidethe organism. The metaphor has no roomfor the complexities of ontogenesis. Sayingthat Raskolnikov had a criminal instinctlabels his criminality as having an internalgenesis, but does not explain how it devel-oped, because everyone agrees that instinctscan be overcome (a left-handed child can betaught to use his or her right hand instead).

The notion of ‘innate ideas’, which is evident in philosophy from Plato to Leibnitzand beyond, divides ideas into those thatspring from within and those that are causedby anything else. The idea thus amounts tolittle more than an opposition to learningtheory — to call an idea or principle ‘innate’ is to claim that it is unlearned. Thefolk-psychological metaphor of innatenessexhibited in classical philosophy can perhapsbe forgiven for its explanatory failure, butscience cannot. Do terms such as ‘innate’ and‘instinct’ embody at least the beginnings of acoherent explanatory concept? Or do theyoccur in contemporary psychological andbiological literature as fossilized folk labelswith no explanatory function?

We see the concept of instinct used with atleast some explanatory force when Darwinwrote, in The Descent of Man, that instinctsare “gained step by step, through the variabil-ity of the mental organs and natural selection,without any conscious intelligence on thepart of the animal during each successive generation”. He was saying that, as long asthere is variation of heritable propensities forbehaviour within a population, the distalcauses of instincts are environmental. Thisdoes more than label the source of instinct. Itprovides an explanation of how innatebehavioural capacities arise: they are theresult of selective pressures on a population.The metaphor suggested by the prefix ‘in-’ of‘inborn’, ‘instinct’ and ‘innate’ is thus attenu-ated somewhat.

But there is also a weakening of the folk-psychological idea that what is innate isunlearned; in fact, this idea does not reallysurvive at all in the darwinian view. Darwin

wrote that he was “very far from wishing todeny that instinctive actions may lose theirfixed and untaught character, and bereplaced by others performed by the aid offree will”. He noted in On the Origin of Speciesthat ‘instinct’ is not definable, and does notdenote a natural class. Instead, ‘instinct’ represents a cluster concept — some, but notall, instincts are unlearned.

It is not going too far to say that Darwinexplains the origin of instincts at the cost ofbeing unable to characterize what is beingexplained. Instinctive behaviours no longerclearly originate inside the organism, nor arethey uniformly unlearned.

By the late nineteenth century, ‘instinct’was being used by psychologists to label avast collection of behaviours and capacities;one disgruntled critic counted 280 exam-ples. Someone had to try to make a scienceout of this burgeoning catalogue. That was the task taken on by the anti-behaviouristKonrad Lorenz — disregarding Darwin’swarning that instincts are not a natural class.Lorenz’s theory of instincts aimed to identifygenetically determined, species-specifictraits that can be explained by natural selec-tion. As far as he was concerned, the internalorigins of instincts are genetic, and this factalone can explain how individual organismscome to develop stable, developmentallyfixed behaviours. They would therefore bemanifest in isolation experiments, whichwere supposed to show what an organismdid when deprived of any opportunity tolearn a behaviour through interaction withan external environment. With Lorenz, then, the internal/external dichotomy offolk-psychology returns in force. But theunderlying assumption that there is a vastdifference between instincts and all otherbehaviours remains unexplored.

Lorenz was widely criticized for his fail-ure to understand the relationship betweengenes and behaviour, and for simplylabelling this relationship “maturation”.Early critics such as Daniel Lehrman com-plained that not only did Lorenz misconceiveorganism–environment interactions, butmore importantly, he used the concept ofmaturation as a way of ignoring develop-mental complexity.

It would seem, then, that if the folk-psychological idea of what is innate is to befitted into a biologically grounded psychol-ogy, it will have to be based on a dichotomybetween genetic information on the onehand and everything else on the other.

The recent trend known as developmen-

tal systems theory (DST) rejects suchdichotomizing. In fact, it rejects the entireinternal/external distinction that is endemicin folk-psychological ideas of innateness,and recommends the abandonment of suchunhelpful metaphors. In the DST view,nature/nurture disputes cannot be resolvedby research into how much must be attrib-uted to internal factors and how much toexternal ones. Such investigations merelyrehash the dispute. It is not news that organ-isms select their environments, and thatenvironments are inherited by organisms.Nor should it be news that focusing obses-sively on which parts are innate and whichare not obscures understanding of develop-mental processes. What is news is thatdichotomous metaphors must be dissolvedby recasting our conceptions of heritabilityand natural selection to include both what iswithin and what is without.

For the proponents of DST, in otherwords, Raskolnikov was a criminal neithersolely because of a criminal instinct withinhim, nor solely because the environment of StPetersburg criminalized him. Yet somehow,he developed into a criminal, nonetheless.The complex, web-like processes of that development could be a profitable subject for science as well as novels. ■

Barbara C. Scholz is in the Department of Philosophy,San José State University, San José, California, USA.

FURTHER READINGOyama, S., Griffiths, P. E. & Gray, R. D. Cycles ofContingency: Developmental Systems and Evolution(MIT Press, Cambridge, Massachusetts, 2001).Oyama, S. Evolution’s Eye: A Systems View of theBiology–Culture Divide (Duke Univ. Press, Durham,North Carolina, 2000).

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NATURE | VOL 415 | 14 FEBRUARY 2002 | www.nature.com 739

Criminal creation: the misdeeds of Crime andPunishment’s Raskolnikov (here in a 1935 film)were probably born of both ‘instinct’ and society.

InnatenessReconciling ‘instinct’ with biological reality mayrequire a recasting of evolutionary metaphors.

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