03 January 2010

Social Externalism, Senses, and Frege's Puzzle

Akeel Bigrami's "Naturalism and Reference" is pretty terrific.

There's a bit in Bilgrami's Crispin Wright piece (also on his website) that I'd been puzzling over for a while. Bilgrami argues there that if an individual can fail to know the sense of one of his expressions, then Frege's puzzle rears its head again (and so the original motivation for positing senses falls away). So social externalism (a la Putnam, Kripke, or Burge) must be false: what I mean can't depend on what my social group says I mean. This is an attractive conclusion, but I couldn't follow Bilgrami's argument for it. Turns out "Naturalism and Reference" is largely devoted to laying out this argument.

It seems that the inspiration for the argument comes from a criticism Jerry Fodor makes against senses (following someone named "Mates" who Bilgrami doesn't cite; I will simply credit Fodor for this line of thought in my post). Fodor wants to handle all of language denotationally -- only reference, not sense, strikes Fodor as naturalistically acceptable. (I'll leave Fodor's supposed naturalistic reconstruction of reference out of this; I'll also not be concerned with Fodor's response to the puzzles, but only with his criticism of the orthodox (Fregean) response.) Now, this is just the position that Frege is arguing against in "Sense and Reference".

As a reminder, the challenge Frege poses for such a position is to make sense of the difference between "Hesperus" and "Phosphorus" in sentences like

a) John believes that Hesperus is visible from his window in the evening.
b) John does not believe that Phosphorus is visible from his window in the evening.

Given a purely denotational theory of meaning, it looks like John is irrational (since Hesperus is Phosphorus; they're two names for the planet Venus). But John needn't be irrational for sentences a and b to both be true; John could simply be ignorant of the fact that "Phosphorus" names the same heavenly body as is visible early in the evening. A purely denotational account of meaning thus seems committed to treating garden-variety ignorance of this sort as a failure of logic: John is said to both believe and not believe the same proposition.

The same issue arises also in our attempt to evenstate the puzzle: if "Hesperus" and "Phosphorus" have the same meaning (since they denote the same planet), why would it be wrong to rephrase b as b'

b') John does not believe that Hesperus is visible from his window in the evening.

since b and b' ought to be the same sentence?

Thus Frege posits "senses", ways in which a subject is presented with objects, as a component of meaning alongside reference. "Hesperus" and "Phosphorus" are said to have different senses despite having the same reference, and thus the puzzles dissolve. So goes Frege's account.

Fodor does not see how this is supposed to help. He asks why the puzzle can't simply arise again at the level of sense. Suppose "Besperus" has the same sense as "Hesperus", but John doesn't know that; you can then replace b with b''

b'')John does not believe that Besperus is visible from his window in the evening.

and it looks like Frege's puzzle arises anew. Now, this requires that it be possible for someone to fail to know the sense of something they (e.g.) utter. But Fodor thinks that this could easily happen, on Frege's picture. For Frege, senses are Platonic entities which exist in the Third Realm (being neither mental nor physical, and being the common inheritance of the whole human race); they are entities which we express in our various human tongues. Now, if senses are at all like other entities, then we should be able to misidentify them: we can grasp a sense without knowing all of the senses it's identical to. I can grasp a mug without knowing it's identical to the mug you forgot to wash, or used to rinse your mouth with; likewise I should be able to grasp a sense without knowing everything about it, e.g. that the sense of "Besperus" is identical to the sense of "Hesperus". And if John does just this, then you can recreate Frege's Puzzle with a and b''. "Hesperus" and "Besperus" have the same reference and the same sense, and yet there is a difference between them that stands unexplained.

Bilgrami takes this as a good reason to reject Platonism about senses, and that seems right to me. If senses are not entities which are present to the mind, but are simply ways in which referents are present to the mind, then this puzzle doesn't arise. If "Besperus" and "Hesperus" have the same sense, then they present one with an object in the same way, and John can't be confused in the way this puzzle posits. Seeing something in a certain way doesn't meant that one sees two items, the "something" and the "certain way". Like Carnap said, being in a state does not mean there exists a state which one is in (unlike being in a can, which does mean that there exists a can that one is in).

(As an aside, I suspect that Frege just thought (or would've thought if anyone raised this puzzle to him) that we couldn't grasp senses without identifying them perfectly; they are really weird like that. "Grasping of senses" thus looks like some magical happening, but I don't think Frege was worried by that sort of thing at all: it's a problem for psychology, not logic, how "grasping" is supposed to work (says Frege in "The Thought"). This is of course not a very happy position for anyone less willing to burden psychologists than Frege was, i.e. for anyone other than Frege himself.)

But, this is not the only possibility Fodor raises for someone getting senses wrong. Even if senses are not entities, it might be the case that (as many in the literature have claimed, e.g. Tyler Burge and Hilary Putnam) sense is dictated by one's linguistic community. "Social externalists" about meaning say that the sense of what one says depends on what one's words mean in the language one is speaking, where a language is an essentially social/shared/public creature (like French or Mandarin), something with a community of users that can criticize/endorse various uses of words. One makes noises, and then they mean what the communal norms say they mean. (This is perhaps an uncharitable way of putting it, since the relevant community is always supposed to be something of which the speaker is a part. Still, the point remains that for social externalists, one can mean something radically different than what one thought one meant, because of how a word is used in one's linguistic community [apart from oneself].)

Now, the problem here is fairly straightforward: Suppose "bachelor" and "unmarried man" have the same (social externalist) sense in a given linguistic community of which John is a member. Then you can recreate Frege's puzzle with c and d:

c) John believes that Tom is a bachelor.
d) John does not believe that Tom is an unmarried man.

Now, this might seem queer at first glance; it might be thought that John can't be truly described by c and d without being irrational, so you can't reframe Frege's puzzle in these terms. (The issue of the analytic/synthetic distinction is tied up in how one reacts to this; Bilgrami has a lovely brief parenthetical about this on page 12 of his paper that he says he won't be elaborating on for reasons of space. I will plead similarly.) I think this can be smoothed by adding e to the mix

e) John believes that to be a bachelor is to be a bearded Oxford alumnus, and that bearded Oxford alumni may or may not be married.

i.e., if we say that John is a member of the linguistic community who thinks some strange things. The social externalists are committed to this not disbarring John from the linguistic community, as the discussion in the literature of a fellow who says "I have arthritis in my thigh" shows: they would say of John that he believes of unmarried men that they may or may not be unmarried (but must have beards and diplomas from Oxford). Social externalists thus think that one can fail to know (at least on odd occasions) what senses one's words have. And so Fodor complains that adding senses to the picture doesn't dissolve Frege's puzzle; they simply push it back a level. For c and d can both be true despite "bachelor" and "unmarried man" having the same sense (and the same extension), and this is not a case of John being irrational but of him being ignorant of an empirical fact (i.e. that his linguistic community treats "bachelor" as a synonym for "unmarried man" and not for "bearded Oxford alumnus"). So senses fail to do the job demanded of them.

Fodor is right: if social externalists are right about senses, then senses don't take the teeth out of Frege's puzzle. But the correct move (says Bilgrami, and I agree) is to modus tollens this modus ponens and reject social externalism about sense. One can't fail to know the sense of what one says, contra social externalism (at least one can't fail to know it due to philosophical problems -- one can mean things without knowing it due to e.g. Freudian-style unconscious intentions to insult the reader, or in other psychologically interesting diseases of rationality; these weird psychological phenomena are not what motivate social externalist accounts of sense, and I believe they are largely a distraction from the issue under discussion).

So, there's a pretty little argument that social externalism gives a false account of senses, couched in Fregean terms: the things that dissolve Frege's puzzle from "Sense and Reference" can't fly free of the subject's grasp like the social externalist picture lets them. (Too bad I didn't get clear on this before I finished my thesis; it would've been nice to work it in somewhere.)

1 comment:

Presskorn said...

On a peripheral note: "Mates" probably refers (altough perhaps not all that rigidly) to Benson Mates, the recently deceased proffessor of philosophy from Berkeley...