Jean-marc pizano Frege to the contrary notwithstanding, it looks as though practically any linguisticdifference between prima facie synonymous expressions, merely syntactic differences distinctly included, can berecruited to block their substitution in some Mates context or other. In thecurrent jargon, the individuation of the propositional attitudes apparently slices them about as thin as the syntacticindividuation of forms of words, hence not only thinner than reference can, but also thinner than sense can.
The other obstacle to saving the Frege programme was that it took for granted that the semantic question ‘How can coreferential concepts fail to be synonyms?’ gets the same answer as the psychological question ‘How can there bemore than one way of grasping a referent?’ The postulation of senses was supposed to answer both questions. Iargued, however, that given Frege’s Platonism about senses, it’s by no means obvious why his answer to the firstwould constitute an answer to the second; in effect, Frege simply stipulates their equivalence. I supposed the moral tobe that Frege’s theoretical architecture needs to be explicitly psychologized. Modes of presentation need to be ‘in thehead’.
The short form is: the Frege programme needs something that is both in the head and of the right kind to distinguish coreferential concepts, and the Mates cases suggest that whatever is able to distinguish coreferential concepts is apt forsyntactic individuation. Put all this together and it does rather suggest that modes of presentation are syntacticallystructured mental particulars. Suggestion noted.
The other research programme from which my budget of constraints on theories of concepts derived is the attempt, in cognitive science, to explain how a finite being might have intentional states and capacities that are productive andsystematic. This productivity/systematicity problem again has two parts: ‘Explain how there can be infinitely manypropositional attitudes each with its distinctive propositional object (i.e. each with its own content)’ and: ‘Explain howthere can be infinitely many propositional attitudes each with its distinctive causal powers (i.e. each with its own causalrole in mental processes).’ Here I have followed what Pylyshyn and I (Fodor and Pylyshyn 1988) called the ‘Classical’computational tradition that proceeds from Turing: mental representations are syntactically structured. Theirconditions of semantic evaluation and their causal powers both depend on their syntactic structures; the formerbecause mental representations have a compositional semantics that is sensitive to the syntactic relations among theirconstituents; the latter because mental processes are computations and are thus syntactically driven by definition. So theClassical account of productivity/systematicity points in much the same direction as the psychologized Fregeprogramme’s account of the individuation of mental states: viz. towards syntactically structured mental particularswhose tokenings are matched, case for case, with tokenings of the de dicto propositional attitudes.
Syntactically structured mental particulars whose tokenings are matched, case for case, with tokenings of the de dicto propositionalattitudes are, of course, exactly what RTM has for sale. So RTM seems to be what both the Frege/Mates problems andthe productivity/systematicity problems converge on. If beliefs (and the like) are relations to syntactically structuredmental representations, there are indeed two parameters of belief individuation, just as Frege requires: Morning Starbeliefs have the same conditions of semantic evaluation as Evening Star beliefs, but they implicate the tokening ofdifferent syntactic objects and are therefore different beliefs with different causal powers. That believing P andbelieving Q may be different mental states even if ‘P and Q have the same semantic value shows up in the Matescontexts. That believing P and believingQ may have different causal powers even if ‘P and ‘Q have the same semanticvalue shows up in all those operas where the soprano dies of mistaken identity.
So RTM looks like a plausible answer to several questions that one might have supposed to be unrelated. I hope that isn’t an accident. This book runs on the assumption that it isn’t, hence that we need RTM a lot. RTM, in turn, needs atheory of concepts a lot since compositionality says that the contents and causal powers of mental representations areboth inherited, eventually, from the contents and causal powers of their minimal constituents; viz. from the primitiveconcepts that they contain. RTM is simply no good without a viable theory of concepts.