Searle, The Myth of the Computer

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Searle, The Myth of the Computer

• Thesis Computers cannot be minds.

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Two levels of explanation of human behavior

• 1. Commonsense psychology use beliefs and
  desires (perhaps also hidden motives and
  self-deceptive beliefs) to explain why people act
  as they do, (mental level)
• 2. Neurophysiology scientific explanations of
  how the brain works, how it results in responses
  and behaviors. (physical level)

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• Could there be a third level of explanation which
  integrates the two and explains the interaction
  between mind and brain?
• Searle claims to have seen many attempts fail in
  his lifetime e.g., behaviorism, Freudian
  psychology. He thinks that AI is bound to fail.

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Strong AI Thesis

• Minds are very complex digital programs.
• Mental states are computer states, and any system
  with the right program and the right input would
  produce the right output.

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Objections to Strong AI Thesis

• 1. Implausible to think that specific biochemical
  powers of brain are irrelevant to the mind
• 2. Computers dont symbolize or represent
  anything, they are just formal counters. But to
  be a mind or to have consciousness of the human
  sort, one has to be able to use symbols to
  represent ones thoughts.

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Syntax/Semantics

• Syntax the formal properties of a formal system
  or language, including the tokens or symbols that
  are considered to be part of the language, and
  the rules for combining the symbols.
• Semantics the meanings or interpretation of the
  symbols and the well formed symbol strings.

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Symbols two lives

• Formal tokens or symbols can thus have two lives
  a syntactical life, in which they are meaningless
  markers moved according to the rules of a
  self-contained game, and a semantic life, in
  which they have meanings and significant
  relations to the world.

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The Chinese Room Example

• The man in the room has a syntax, but no
  semantics, and this is just the situation of the
  computer.
• What does it take to have semantics?

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Searles Interpretation

• What this simple argument shows is that no
  formal program by itself is sufficient for
  understanding, because it would always be
  possible in principle for an agent to go through
  the steps in the program and still not have the
  relevant understanding. (Searle, p.211)
• Does Searle beg the question about what it is to
  understand a language?