The Death of Computationalism

杜國正資訊工程學系49521011

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Computationalism

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mindsⅡ

information-processing systems

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information from world(input)↓

brain + mind(hardware + program)

↓mental state change, behavior, etc.

(output)

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brain = hardwaremind = program

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brain = hardwaremind = program

(?)

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Chinese Room[John Searle, 1980]

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Chinese request(input)↓

a monolingual English-speaking man+ a set of rules written in English

(hardware + program)↓

Chinese response(output)

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Understanding?

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He is a good guy.

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He is a good guy. → (PropN.) + (V.) + Indet. + (Adj. + N) → NP + V. + (Indet. + NP) → NP + (V. + NP) → (NP + VP) → S

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He is a good guy.

Who is `he?'

What's the meaning of `good?'

Is there any hidden message?

How does `he' look?

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Syntax ≠ Semantics

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?

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More formal version...[John Searle, 1990]

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3 Axioms

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(A1) Programs are formal

(A2) Minds have mental contents

(A3) Syntax by itself is neither constitutive of nor sufficient for semantics

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(A1) Programs are formal (syntactic) Have ability to manipulate symbols (using syntax) But don't know what they mean

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(A2) Minds have mental contents (semantics) Our thoughts have meanings They represent things and we know what are they

represent

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(A3) Syntax by itself is neither constitutive of nor sufficient for semantics Already showed by Chinese Room thought exp.

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(A1) Programs are formal (syntactic) (A2) Minds have mental contents (semantics) (A3) Syntax by itself is neither constitutive of

nor sufficient for semantics

Leads conclusion (C1) Programs are neither constitutive of nor

sufficient for minds

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Thus,

mind ≠ program

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Given another axiom:

(A4) Brains cause minds basic modern scientific consensus

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Leads another conclusion:

(C2) Any other system capable of causing minds would have to have causal powers (at least) equivlent to those of brains

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Further: (C1) and (C2)

no programs can produce minds“equivlent casual powers” produce minds

→ (C3) programs do not have those powers

→ (C4) brains do not use programs to produce minds

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Thus,

brain ≠ hardware… that uses programs to produce mind

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References:

➔ http://en.wikipedia.org/wiki/Computationalism➔ http://en.wikipedia.org/wiki/Cognitivism_(psychology)

➔ http://en.wikipedia.org/wiki/Chinese_room

➔ http://www.iep.utm.edu/c/chineser.htm

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The End