Friday, 4 April 2008

McDowell's Truth Theory and Frege Puzzles (Jackie Carter)

In what follows, Jackie Carter offers a clear and concise summary of McDowell's proposed solution to the Frege Puzzle. Enjoy!

So, I think that McDowell's concept of truth seems somehow unsatisfying on its face.... [H]owever, I came to find it much more palatable -- in part because of its implications for philosophy of language and in particular the Frege Puzzle. Anyway, this is my effort to explain why McDowell's truth theory, which makes "true" a status internal to a world view, helps solve the elusive Frege Puzzle. (Disclaimer: my grasp of this feels rather tenuous.)

Recall that (briefly put) Frege's Puzzle is that "Hesperus=Hesperus" seems to have a cognitive value different from that of "Hesperus=Phosphorus." The problem is that if all the proper names do is pick out some referent (some object in the world), then the two identities seem to do the very same thing - the latter seems no more informative than the former. Intuitively, Frege thinks we should avoid this conclusion, so he proposes that names not only pick out referents but also have "senses." So, in the first identity, the sense of the name is the same on both sides, while in the second identity the senses are different. QED, the second identity is of greater "cognitive value" because it involves equating two different senses.

But then the question is what exactly is the "sense" of a word? Frege wants it to play the intensional role of meaning, though he leaves the concept of sense rather mysterious (which then leads Russell and Searle to offer some rather problematic explanations).

McDowell distinguishes between sense and reference as knowledge of truths on the one hand, and knowledge of objects on the other. So, someone who knows the sense of "Hesperus=Phosphorus" has knowledge of a truth, which someone who only knows "Hesperus=Hesperus" is lacking.

{McDowell writes, “Knowledge of the reference of a name…could reasonably be held to be knowledge which, in the context of appropriate further knowledge not itself involving the name, would suffice for understanding utterances containing the name – that is, precisely, knowledge of its sense” (McDowell's "On Sense and Reference," p. 163). }

But if we understand "sense" to be knowledge of truths, we run into problems if truth & truth conditions are purely extensional (as in a deflationary account like Rorty's or even Davidson's). Truth (and along with it, truth conditions) is a mere translational relation between object language and metalanguage, but the "sense" that a given individual associates with a word, sentence, or phrase is supposed to be intensional. Moreover, different people know different truths about different names; e.g., the truths that I know about the object "Hesperus" may differ from those of another. So, how can sense just be knowledge of truth conditions, which would be objective (external, the same for everyone).

The point here is when we say:

"Hesperus = Phosphorus" is true iff Hesperus is Phosphorus,

the right hand side (RHS), which captures the "sense" of the identity, may be different for different agents. For McDowell, truth is intensional, so when we disquote (ie, move over to the RHS), we are already talking about the conception of an agent (we are internal to the world view of an agent). Because truth and truth conditions are intensional, sense is intensional, which enables it to play to intensional role of meaning. That is, the notion of sense, knowledge of truths or truth conditions, can thus capture the intensional notion of meaning.

In short, McDowell’s understanding of truth as internal to the worldview of an inquirer allows him to make truth, and therefore sense, an intensional concept. For McDowell, an account of truth conditions cannot be decoupabled from an account of agents’ beliefs. The right hand side of a Tarski sentence gets at an agent’s worldview and tells us something about her beliefs.

For Davidson, by contrast, a truth theory must include both an extensional account of truth conditions and an intensional account that derives from empirical human behavior. For McDowell, there is no reason to separate these accounts. It is unclear how (and if) someone with an extensional, deflationary truth theory like Davidson's can explain meaning, i.e. sense. So the Frege puzzles seem to go unsolved if truth conditions (the RHS of T-sentence) do not get us to the intensional perspective.

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