There is a standard story about the emergence of the identity theory. Namely, before (say) 1956, because the concept of an experience was not synonymous with the concept of a brain state, we knew a priori that experiences could not be brain states. Let’s call this the semantic argument against identity theory.
It was eventually pointed out that you could have different concepts that refer to the same object (e.g., lightning and electrostatic discharge), at which point identity theory became viable again.
There are two references I hae that suggest the semantic argument was a real force, in analytic philosophy, that blocked the identity theory. First, UT Place, in ‘Is Consciousness a Brain Process?’, wrote:
The all but universally accepted view that an assertion of identity between consciousness and brain processes can be ruled out on logical grounds alone derives, I suspect, from a failure to distinguish between what we may call the ‘is’ of definition and the ‘is’ of composition.
Basically he is saying that even if it is not definitional of ‘consciousness’ that it is a brain process, that is not sufficient to show that it isn’t a brain process. As he goes on to say, he considers such identity claims to be “a reasonable scientific hypothesis, in the way that the statement, “Lightning is a motion of electric charges, ” is a reasonable scientific hypothesis.”
Putnam makes the point more explicitly in his essay ‘Mind and Body’ when recounting the history of the identity theory:
[An old-school philosopher] frequently regards talk of properties as interchangeable with talk of concepts. For such a philosopher, properties cannot be the same unless it is a conceptual truth that they are the same; in particular, the property of having a sensation with a certain qualitative character cannot be the same as the property of being in a certain brain-state, since the corresponding predicates are not synonymous…
Was such a semantic argument, specifically against identity theory, ever clearly made in writing? I’m looking for references.
If both Place and Putnam hadn’t said what they did, I would find it unbelievable that people would have bought the force of the semantic argument. Long before Ryle, Frege’s claims about sense and reference already established that
co-referring terms don’t have to have the same meaning (e.g., morning
star evening star). Were Place and Putnam referring to actual people, or to the zeitgeist in the heyday of analytic philosophy?
Perhaps some might say the semantic argument was implicit in Ryle, who thought that concepts about mental states could be analyzed, without remainder, into claims about behaviors and behavioral dispositions. However, this seems a different argument: Ryle claimed that a behavioral analysis literally left nothing out, so there is nothing left for a neuronal story to do once the behavioral story was told. That, I think, was the “logical” error Ryle spoke of, the “category mistake” of thinking that there was more to the mind than behavior. Asking where the ‘mind’ is once behavior has been delineated is like asking where the ‘university’ is once all of the buildings, people, and other details of the university have been delineated. This seems to be different than the semantic argument as I have described it.
So, am I wrong about Ryle: did he actually use the semantic argument against identity theory? And regardless of Ryle, are there clear instances of the argument anywhere in the literature?