defense Smarts of the identity theory
phil 20208 Je Speaks September 7, 2006
1 Four theories of sensation reports . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Smarts statement of the identity theory . . . . . . . . . . . . . . . . . . . . . . 3 Objections to the identity theory . . . . . . . . . . . . . . . . . . . . . . . . . .
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1
Four theories of sensation reports
In the opening pages of Sensations and Brain Processes, Smart discusses four very different views about what one is doing when one says things like I have a yellowish-orange after image: We are reporting an irreducibly psychical something. This goes naturally with a dualist view of mental properties, on which events like having after-images are irreducibly psychical. We are reporting our behavioral dispositions. This goes naturally with a behaviorist view of sensations, on which sensations are patterns of and dispositions to perform certain behavior. We are not reporting anything. This is the view that Smart attributes to Wittgenstein. On this view, reports of sensations are more like expressions e.g., crying, wincing, laughing than they are like descriptions of happenings of some sort or other. We are reporting a brain process. This goes naturally with an identity theory of sensations and other mental events, on which they are identical with (the same thing as) brain processes. This the view that Smart wants to defend. Ultimately, Smart nds each of the rst three options wanting. He rejects the idea that sensations are irreducibly psychical on grounds of parsimony, and because they would be nomological danglers. He rejects the behaviorist view on the grounds that afterimage sensations, unlike (perhaps) pain sensations are not associated with a stable class
of behavioral dispositions. He rejects the expressivist view on the grounds that when we report after-images we are genuinely reporting something. This leaves the view that we are reporting a brain process as the only view standing. Our next step is to understand what that view involves.
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Smarts statement the of identity theory
Smart describes his view of sensations as follows: Let me rst try to state more accurately the thesis that sensations are brain processes. It is not the thesis that, for example, after-image or ache means the same as brain process of sort X . . . It is that, in so far as after-image or ache is a report of a process, it is a report of a process which happens to be a brain process. . . . All it claims is that in so far as a sensation statement is a report of something, that something is in fact a brain process. Sensations are nothing over and above brain processes . . . When I say that a sensation is a brain process or that lightning is an electric discharge, I am using is in the sense of strict identity. . . . When I say that a sensation is a brain process or that lightning is an electric discharge I do not mean just that the sensation is somehow spatially or temporally continuous with the brain process or that lightning is just spatially or temporally continuous with the discharge. (144-5)
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Objections to the identity theory
After presenting the theory, Smart turns to a series of replies to what he takes to be the most pressing objections to the theory. We will discuss the following objection...