The Chinese Room Argument Part II Joe Lau Philosophy HKU

The issues 4 Certain computations are sufficient for cognition (computational sufficiency). –Objection : The Chinese room argument –Evaluation : Not valid. 4 A more general argument –The argument from syntax and semantics

The argument 4 Computer programs are formal (syntactic). 4 Human minds have mental contents (semantics). 4 Syntax is neither constitutive of nor sufficient for semantics. 4 Conclusion : Programs are neither constitutive of nor sufficient for minds.

Initial comments 1. Programs are formal. 2. Minds have contents. 3. Formal syntax not enough for contents. Conclusion : 4. Programs not enough for minds. Comment #1 : The argument is valid. That is, if the premises are true, the conclusion must also be true. So we have to decide whether premises 1 to 3 are true or not. Comment #2 : The second premise is obviously true. To have a mind, one must have mental states with content. Thoughts, beliefs, desires all have content (intentionality, aboutness). Brentano’s “mark of the mental” Comment #3 : The Chinese room argument is an argument is supposed to provide independent support of premise #3.

First premise : “Programs are formal” 4 True in the sense that : –Symbols are defined independently of meaning. –Computational operations are defined without reference to the meaning of symbols. 4 False in the sense that : –Programs cannot / do not contain meaningful symbols. –The function of symbols is to encode content!

Third premise : “Syntax not sufficient for semantics” 4 Question : Do the symbols have meaning or not? –If so, then there is content / semantics. –The symbols in the Chinese room do have content. –Symbols in AI programs can have assigned content. –So programs with meaningful symbols might still be sufficient for minds.

What is “semantics” for Searle? “Having the symbols by themselves … is not sufficient for having the semantics. Merely manipulating symbols is not enough to guarantee knowledge of what they mean.” So having meaningful symbols in a system is not enough for mental content. The system must know what those symbols mean. But why?

Response 4 Mental representations (symbols) are used to explain intentional mental states. –E.g. X believes that P = X has a mental representation M of type B with content P. –X is not required to “understand” M. 4 They cannot do that if they themselves have to be understood or interpreted. –Infinite regress otherwise.

Summary 4 Searle thinks that the symbols in a system must be understood / interpreted by the system to generate meaning / understanding. 4 Begs the question against the thesis of computational sufficiency : –Understanding is having symbols that encode information in the right way. –The symbols do not require further understanding or interpretation.

Remaining issues 4 Suppose formal operations on meaningful symbols can be sufficient for mental states. 4 Q1 : Where do the meanings of symbols come from? 4 Q2 : Can formal operations be sufficient to give symbols meaning?

Where does meaning come from? 4 The meaning of words (linguistic meaning) depends on conventions governing their use. 4 Words are “voluntary signs” (John Locke)

A different theory is needed 4 The theory of linguistic meaning does not apply to mental representations : –No conventions governing the use of the mental representations. –Presumably we cannot change the meanings of mental representations arbitrarily through conventions.