Searles Argument

1
Searles Argument

• The Chinese Room

2
Types of Argument

• Empirical Arguments
• What do the experiments (models) show?
• Example What does Deep Blue tell us about
  machine intelligence?
• Conceptual arguments
• Example
• Computers couldnt think because computers are
  programmed, and being programmed is incompatible
  with thinking

3
Turings Position

• Whats the argument?
• Is it empirical or conceptual?
• Conceptual argument that empirical evidence
  should decide the issue.

4
Searles Approach

• Offers a conceptual argument to show that
  machines cannot think.

5
Consciousness vs. Intentionality

• Conscious states feeling pain, seeing color
• Intentional states (also called propositional
  attitudes) having a belief, desire, knowing
  something, etc.
• Turing, and Searle criticizing Turing, are
  concerned about whether machines can think, that
  is, whether they can have intentional states.

6
The thought experiment

• Can a digital computer have the intentional state
  of understanding? (E.g. Ignat understands that
  grass is green.)
• Background Research in AI has attempted to build
  digital computers which can understand texts.
• Thought experiment Imagine a computer which
  exhibits the same behavior as a person who
  understands Chinese. (It passes a version of the
  Turing Test.)
• Imagine that you are the central processing unit
  (CPU) of that computer.
• Searle thinks that the CPU, the person, doesn't
  understand.

7
Analysis - simple argument

• Computer programs are formal.
• Human minds have mental contents
• Syntax by itself is neither constitutive of nor
  sufficient for semantics
• Conclusion Programs are neither constitutive of
  nor sufficient for minds.

8
Syntax vs. Semantics

• Syntax formal arrangement of tokens
• Semantics meaning of the tokens.

9
Searle's fuller commentary - simulation vs. real
nature

• Searle thinks that computers can simulate
  intelligence, but not be intelligent.
• A computer simulation of digestion isnt
  digestion.
• A computer simulation of intelligence isnt
  intelligence????
• Searle's holds that real intelligence requires
  the causal powers that brains have. Without
  those, no simulation, no matter how good, is real
  intelligence

10
Objections and Searles responses

• Systems Objection
• CPU doesnt understand, but the whole computer
  does.
• Robot Objection
• Give the computer a body, and it understands.
• Other Minds Objection
• Only know other people think by analyzing their
  behavior. The same goes for the computer.

11
Searles Conclusion

• Merely symbol manipulating doesn't give you
  intentionality.
• Meaning is derivative It is in the minds of the
  programmers.
• Chinese room shows this The formal system does
  not add any intentionality.
• Stones, water pipes, silicon and copper etc. are
  the wrong kind of "stuff" to have intentionality.