Wednesday, April 25, 2007

Gavagai again again

A new version of my discussion of Quine's "argument from below" is now up online (shorter! punchier! better!) Turns out it was all to do with counterpart theory all along.

Here's the blurb: Gavagai gets discussed all the time. But (unless I'm missing something in the literature) I've never seen an advocate of gavagai-style indeterminacy spell out in detail what exactly the deviant interpretations or translations are, that incorporating the different ways of dividing reference (over rabbits, rabbit-stages or undetached rabbit-parts). And without this it is to say the least, a bit hard to evaluate the supposed counterexamples to such interpretations! So the main job of the paper is to spell out, for a significant fragment of language, what the rival accounts of reference-division amount to.

One audience for the paper (who might not realize they are an audience for it initially) are folks interested in the stage theory/worm theory debate in the philosophy of persistence. The neuvo-Gavagai guy, according to me, is claiming that there's no fact of the matter whether our semantics is stage-theoretic or worm-theoretic. I think there's a reasonable chance that that he's right.

Stronger than this: so long as there are both 4D worms and instantaneous temporal parts thereof around (even if they're "dependent entities" or "rabbit histories" or "mere sums" as opposed to Real Objects), the Gavagai guy asks you to explain why our words don't refer to those worms or stages rather than whatever entity you think *really are* rabbits (say, enduring objects wholly present at each time).

By the way, even if these semantic indeterminacy results were right, I don't think that this forecloses the metaphysical debate about which of endurance, perdurance or exdurance is the right account of *persistence*. But I do think that it forces us to think hard about what the difference is between semantic and metaphysical claims, and what sort of reasons we might offer for either.

Parsimony and the fundamental (x-posted from metaphysical values)

A bit cross-posting this one...

In his APA comments on Jonathan Schaffer, Ross asks about some of Jonathan's ideas about the applicability of Ockham's razor. The question arises if you buy into some robust distinction between "fundamental" and "derivative" existents. Candidate fundamental existents: quarks, electrons, maybe organisms (or maybe just THE WORLD). Candidate derivative existents: weirdo fusions, impure sets, maybe tables and chairs (or maybe everything except THE WORLD).

Let's call the idea that "derivative" as well as "fundamental" entities are (thump table) existing things the expansivist interpretation of the fundamental/derivative distinction. Call the idea that only the fundamental (thump table) exists the restrictivist interpretation of that distinction.

Jonathan's position is that Ockham's razor, rightly understood, tells us to minimize the number of fundamental entities. Ross's idea (I think?) is that this is right iff one has a restrictivist understanding of the fundamental/derivative distinction. But Jonathan, pretty clearly, has an expansivist understanding of that distinction: he doesn't want to say that the only thing that (thump table) exists is the world, just that the world is ontologically prior to everything else. So if Ross is right, his application of parsimony is in trouble.

I can see what the idea is here: after all, understanding parsimony as the instruction to minimize (thump table) existents or to minimize the (thump table) kinds of existents is surely close to the traditional understanding. Whereas the idea that we need only minimize (kinds of) existents of such-and-such a type, seems to come a bit out of the blue, and at minimum we need some more explanation before we could accept that revision to our theoretical maxims.

However... One thing that seems important is to consider what sort of principles of parsimony might be present in more ordinary theorizing (e.g. in the special sciences). The appeal of appealing to parsimony in metaphysics is in large part that it's a general theoretical virtue, applicable in all sorts of areas that are paradigms of good, productive fields of inquiry. Now, theoretical virtues in the sciences is not a topic that I'm in a position to speak with authority on. But one thing that seems to me important in this connection: if you think that the entities of special sciences aren't fundamental entities, then principles of parsimony restricted to the fundamentals aren't going to be in a position to give you much bite. (NB: I think that this was raised by someone in comments on Jonathan's paper in Boise, but I can't remember who it was...).

If that's right, then whether you're an expansivist or a restrictivist about the fundamental/derivative distinction seems beside the point. Any theorist who gives a story about what the fundamentals are that's unconstrained by what the special sciences say, is going to be in trouble with the idea that principles of parsimony should be restricted to constraints on fundamental existents: for such principles of parsimony won't then be able to get much bite on theorizing in the special sciences. I'd like to think that quarks, leptons etc are going to populate the fundamental, rather than Jonathan's WORLD. This point bites me as much as Jonathan.

There's plenty of room for further discussion here, particularly the interaction of the above with what you take to be evidence for some entities being fundamental. E.g. if you thought that various types of emergentism in special science would be evidence for "higher level" fundamental entities, then maybe the above parsimony principle would still have application to special sciences: it'd tell you to reduce to the number of emergent entities you postulate (i.e. it'd be a methodological imperative towards reductionism).

Also, it seems to me that there is something to the thought that some entities are simply "don't cares" when applying parsimony principles. If I'm concerned with theorizing about the behaviour of various beetles in front of me, I care about how many kinds of beetles my theory is giving me, but not with how many kinds of mathematical entities I need to invoke in formulating that theory. Now, maybe that differential attitude can be explained away by pointing to the generality of the mathematica involved (e.g. that total science is "already committed to them"). But one natural take would be to look for restrictions to principles of parsimony/Ockham's razor, making them sensitive to the subject-matter under investigation.

To speculate wildly: If principles of parsimony do need to be sensitized in this way, and if the study of what fundamentally exists is a genuine investigation, maybe the principle of parsimony, in application to that study, really would tell us to minimize the number of, and kinds of, fundamental entities we posit.

Monday, April 09, 2007

APA return

Back in Atlanta waiting to reboard a flight to the UK. Trying not to miss the flight this time (interestingly, the plane from SF was an hour out on the "local time" it displayed on board, which might explain the previous problems).

The APA was really fun. Highlights for me included the Hudson-fest, featuring comments from Josh Parsons, Mark Heller and Michael Rae, and interesting replies to each from Hud. Also the author-meets-critics session on dialethism which Brit mentions here. I've been thinking a lot about open futures following Brit's talk on sea battle semantics, and may have some thoughts to post soon (on the plane over to Atlanta, my frantic drawing of dots and arrows trying to figure out how counterfactuals interact with open future semantics convinced my neighbour I was an astrophysicist. Must be the big axes with "time" and "reality" on them...). Andy Egan gave two really interesting papers, on fragmented minds and aesthetic disagreement, and I really enjoyed Alyssa Ney's talk on how different theories of causation fit together (or not). And lots more nice people met and good stuff talked about!

It was fun also meeting various bloggers for the first time in the flesh.

The tale of the 14 philosophers and the limousine is already legendary, I gather (I wasn't there).

Tuesday, April 03, 2007

San Francisco

San Francisco! I'm staying at a hotel with a very posh lobby, the Sir Francis Drake, just down the street from the APA venue. I've enjoyed a hour-long double-decker train journey, and am just being struck once more about the strangeness of being in a different country.

I think food may be in order, then recovery before the hard philosophical slog restarts...

Monday, April 02, 2007

To the APA

The Boise metametaphysics conference finished today. A really fun event! I gave quick versions of my comments on Ted's naturalness paper this morning.

One thing that was kind of surprising to me is that there weren't many people defending the sort of "realist Quinean" view that I (along with a lot of people) took to be the orthodoxy. Carnapians (of various flavours), Aristotelians, and the like were more in evidence.

I found the framework and ideas in Dave Chalmers' "Ontological anti-realism" paper particularly stimulating. It suggests to me some nice ways of extending some of the views I have on ontic vagueness. Lots to think about.

Anyway, I'm now about to get on a plane for San Francisco, for the Pacific APA. It was very exciting seeing the Pacific for the first time as I flew in to SF on the way to Boise; I'm really looking forward to seeing the city and attending the conference.