Taking Seriously Knowledge as a Mental State

Frege, it is often said, liberated the theory of meaning and logic from epistemology. He despised the neo-Kantian Erkenntnistheorie of his time as just another form of psychologism. He was not interested in how we come to know numbers, meanings and logical laws, but in what it is for numbers, meanings, and logical laws, to be the objects of knowledge, independently of any human subject. He accepted that there must be some way in which the various objective entities which he postulated are grasped by the mind and thus known, but he was not interested in spelling out how this was achieved. The positivists, on the contrary, wanted to epistemologise meaning and logic: for them the theory of meaning was epistemology done by other means. 1 So they were interested in how we come to know the meanings of various kinds of statements. The linguistic turn, in its ordinary language version, liberated again the theory of meaning from epistemology: the only kind of knowledge that one needs to understand the expressions of our language is a knowledge of rules and practices associated to them. The formal version of the linguistic turn, which studied the semantics of natural languages through the lenses of formal semantics, was also anti-psychologistic: to know the meaning of expression we need only to know their truth conditions and the abstract functions associating semantic values to possible worlds. It is only recently that the so-called cognitive turn reintroduced epistemological and psychological elements in semantic theory. For the analytic tradition in which the philosophy of language took the place of primary philosophy, the notion of knowledge was never really expelled, but, to use a phrase of D avidson‟s, “epistem ology w as seen in the m irror of the theory of m eaning”. Michael Dummett (1975, 1976) has interpreted F rege‟s insistence on the idea that the sense of an expression is associated with our understanding and our knowledge of what the expression refers to (and in the case of the sense of sentences, of our understanding and knowledge of their truth conditions) as imposing a knowledge constraint of meaning. The meaning of an