Behaviorism

Talk about mental phenomena is shorthand for talk about actual and potential patterns of behavior (quite likely multi-tracked).

Objection: There is no non-circular list of actual and potential behavior conditions that are necessary and sufficient for a mental state.

Identity theory

Each type of mental state is identical with some type of physical state within the central nervous system.

Considerations in favor:

• Our apparent physicality.
• Our mental activity exists for evolutionary reasons; mental activity that exists for evolutionary reasons has a neural grounding.
• Neural dependence and simplicity.
• Prediction: Neuroscience will be successful. This prediction is borne out.

Eliminative materialism

Considerations in favor:

• Lack of success of folk psychology.
• Lack of success in early versions of other scientific theories.
• Other theories are not as good

Considerations against:

• Introspection
• Self-defeat
• Exaggeration

Functionalism

Defining features of mental states are the causal relations to (1) environmental effects, (2) other mental states, and (3) bodily behavior.

Considerations in favor:

• Aliens and functional isomorphism
• Gradual replacement

Considerations against:

• Inverted spectrum (but qualitative character may differ without the state differing)
• Qualia
• Chinese room

Searle’s argument

1. (Premise) If a computer program could understand Chinese, then the person in the Chinese room who memorized all the rules and symbols understands Chinese.
2. (Premise) The person in the Chinese room does not understand Chinese.
3. Therefore, a computer program cannot understand Chinese.

Argument against functionalism

1. (Premise) If functionalism is correct, then a computer program could understand Chinese.

2. (Premise) A computer program cannot understand Chinese.

3. Therefore, functionalism is not correct.