Philosophy 4610

1. Philosophy 4610 Philosophy of Mind Week 4: Objections to Behaviorism The Identity Theory

2. Carnap: “Psychology in Physical Language” • Carnap (1891-1970) was a dedicated physicalist who believed that everything in the world is physical • He argues that we can take any sentence that seems to describe a mental experience or event and rewrite it in a completely physical language.

3. Carnap and Logical Behaviorism • Logical Behaviorism is the view that when we talk about “the mind,” we are really just talking about the behavior of the body (and hence about something that we can describe completely in physical terms. • For instance, we might translate, “Abner is angry” as: “Abner’s face is red; his fist is shaking; and he is yelling.” • How might we translate other “mentalistic” sentences?

4. Logical Behaviorism: objections • Logical behaviorism seems plausible for mental states that are always closely connected to behavior. But what about my mental state of thinking about the weekend or dreaming of a better future? • It seems clear that sometimes our behavior does not manifest our true mental states: for instance we may be acting, or covering up how we truly feel.

5. Logical behaviorism: dispositions • According to Carnap, at least some mental states are actually not actual behaviors but rather dispositions to behave. To say that I am thinking about the future is just to say that I would say “yes” if I were asked whether I was thinking about the future. • Just as a glass can be “fragile” even if it is not actually breaking, I can be in a certain mental state even if I am not actually exhibiting it right now.

6. Dualism and logical behaviorism: Summary • Descartes thought that mind and body were two completely separate substances, interacting through the pineal gland. • Ryle criticizes this view for failing to explain our knowledge of others’ minds and for giving an implausible picture of human beings as “ghosts in machines.” • Carnap’s physicalist picture – logical behaviorism – identifies the mind with outer, public behavior and with dispositions to behave.

7. Putnam: “Brains and Behavior” • Hilary Putnam (1926-) is also a physicalist, but he criticized logical behaviorism and contributed to the development of an alternative theory.

8. Problems with Logical Behaviorism? • If logical behaviorism is true, then every sentence about a mental event must be translatable into a sentence about behavior that means the same thing. • For instance, every time we say, “Mr. A is in pain,” this must be translatable into some sentence about Mr. A’s actual or possible behavior. • But Putnam thinks this is not plausible.

9. Super-Spartans and X-Worlders • To show this, Putnam imagines a race of “Super-Spartans” who are culturally trained never to show any signs of pain. • We can even imagine a race of “X-Worlders” who not only never show pain, but they never even talk about pain.

10. Super-Spartans and X-Worlders • For the X-worlders, it does not even make sense to think that there is any translation from “Mr. X has pain” to a sentence about pain-behavior. Nevertheless it still makes sense to think they may have pain: • “What is true by hypothesis is that we couldn’t distinguish X-worlders from people who really didn’t know what pain is on the basis of overt behavior alone. But that still leaves many other ways in which we might determine what is going on ‘inside’ the X-worlders – in both the figurative and literal sense of ‘inside’. For example, we might examine their brains.” (p. 51)

11. Smart and the Identity Theory • J. J. C. Smart (1920-) gave the classic formulation of the Identity Theory • According to the Identity Theory, the mind just is the brain. When we talk about mental events such as pains, feelings, and sensations, we are just talking about states and processes in the physical brain.

12. Smart and the Identity Theory • Like Carnap and Putnam, Smart is also a physicalist: • “It seems to me that science is increasingly giving us a viewpoint whereby organisms are able to be seen as physico-chemical mechanisms: it seems that even the behavior of man himself will one day be explicable in mechanistic terms. There does seem to be, so far as science is concerned, nothing in the world but increasingly complex arrangements of physical constituents.”

13. Smart and the Identity Theory • But unlike logical behaviorists, Smart thinks that all mental events – such as after-images – can be identified with states of the brain: • “Maybe this is because I have not thought it out sufficiently, but it does seem to me as though, when a person says ‘I have an after-image,’ he is making a genuine report, and that when he says ‘I have a pain,’ he is doing more than ‘replace pain-behavior,’ and that ‘this more’ is not just to say that he is in distress. I am not so sure, however, that to admit this is to admit that there are nonphysical correlates of brain processes. Why should not sensations just be brain processes of a certain sort?” (pp. 61-62)

14. Objections to the Identity Theory • According to the Identity Theory, the mental state of having a toothache or an after-image is the same thing as a certain brain state, X. But we can know about toothaches and after-images without knowing anything about brain states.

15. Response • According to Smart, the identity between an after-image and brain-state X is something we do not necessarily know about before we do science. It’s like the identity between water and H20. We can know all about water without knowing anything about H20, but that doesn’t mean they’re not identical. We just have to do some science to find out that they are.