Sider, structure, reduction, and knowledge first

This is a continuation of yesterday's post. Yesterday I identified what seemed to me to be a problem for the way that Ted Sider wanted to explain why various macro-level things are more privileged—basically, they're said to be more joint-carving. But as I said yesterday, I just don't see that they are.

I suspect, however, that one can get something quite a bit like Sider's picture here if one is willing to add a bit more structure. The prospects for a reasonable purely physical story about chemical objects and properties seem reasonable. It doesn't seem hopeless to try to give a reasonably simple definition of molecule or magnesium or valence in purely physical terms. So if we assume the (absolute) fundamentality of physics, we can run the story Sider wants for why we refer to molecules instead of molecules-or-cucumbers, or even molecules-before-2013-and-regions-of-space-afterwards, because the physical definition of molecule is significantly simpler than these more bizarre properties. (In the former case, a purely physical definition will be insanely complex, as in the case of pig; in the latter, it will still be not insanely complex, but more complex than that for molecule.)

This is basically just a way of expressing the familiar idea that chemistry somehow reduces to, or emerges from, physics. But if we buy into Ted's general ideas, we can add this: it is part of the objective structure of the world that chemical properties are related to physical properties in this way. The 'book of the world' will give us the chemical on top of the physical (and the chemical is objectively privileged over the schmemical).

Now what happens when we go up another level? It's pretty natural to suppose that cell biology relates to chemistry as chemistry does to physics. So --- and here's where the picture I'm describing departs from Ted's --- when adjudicating between which objects we refer to in our discourse about cell biology, objects with reasonably simple definitions in chemical terms --- not physical terms --- are privileged over ones that don't. We don't always go back to the most fundamental; we just go back to the more fundamental domain that is appropriate for the matter at hand. Often, but not always, the simpler definition is the more fundamental theory will correspond to the simpler definition in the ultimately fundamental theory; when it doesn't, I think we should go with the less fundamental one. (It's having a better chemical account that makes a particular referent of 'cell' the preferred one, not having a better physical account.)

The reason I'm interested in this, besides the fact that it's interesting, is that I'm leaning in this kind of a direction as a way of making sense of what the 'knowledge first' attitude is. (Yes, I'm reading metaphysics, but it's in the service of epistemology, I swear!) I understand it as a metaphysical thesis: knowledge is a more fundamental state than has been traditionally recognized. In the terms of this broad way of thinking about theorizing about the world, knowledge shows up at a more fundamental level than one might have thought.  (Compare a 'life first' theorist, who thinks that the attempt to define life in biological terms is a mistake; life's home is really at the chemical level—we need to invoke life to understand, say, combustion.) How early should knowledge appear? Presumably, people could differ about this. If you wanted to, you could think that knowledge was perfectly fundamental; knowledge is as basic as quarks or whatever. You'd oppose any kind of reduction of knowledge to anything. This doesn't sound very plausible, but you could say that if you wanted to. My suspicion is that knowledge will be an important theoretical term from the basics of intentional psychology.

Sider on joint-carving and reference

Humans refer to things sometimes. Ted Sider thinks, with David Lewis, that part of the story for why it is that we refer to some things, rather than other possible things, is that the things we refer to are more natural. This Sider understands as a matter of the primitive structure of the world. To takes one of Ted's examples, Ted's word 'pig' refers to pigs, instead of pigs-before-2011-AD-or-cows-afterwards. And he thinks that general considerations about fundamental structure can yield this intuitive result. Ted writes:

The point may be seen initially by making two strong, crude assumptions about "reasonably joint-carving". Assume first that a notion is reasonably joint-carving iff it has a reasonably simple and nondisjunctive definition in terms of the perfectly joint-carving notions, and second that the perfectly joint-carving notions are those of physics. Then surely no reasonably joint-carving relation that is to play the role of reference could relate a human population to bizarre semantic values. For the bizarre semantic values themselves have no simple basis in the physical, nor do they stand in any physically simple relations to human populations. Given any reduction that does relate us to bizarre semantic values, there is surely some other relation with a simpler basis in the physical that relates us to nonbizarre semantic values. (29)

There is considerable vagueness and imprecision in the notion of "reasonably" simply definitions Ted evokes, but I guess I agree that it's pretty plausible that one couldn't tell a "reasonably simple" story in purely physical terms of how humans are related to bizarre semantic values like pigs-before-2011-AD-or-cows-afterwards. But Ted needs more than just that fact; he needs the comparison. And I guess it just doesn't look very plausible to me that there is a "reasonably simple" definition available in purely physical terms of any of the pieces we need here. By any ordinary standards, a definition of pig --- or human! --- in purely physical terms will be rather unreasonably complex! So I worry that if this is the story about why we don't refer to pigs-before-2011-AD-or-cows-afterwards, it will generalize to show that we don't refer to pigs either. (A related problem; surely it's possible to refer to pigs-before-2011-AD-or-cows-afterwards, right?)

I think this problem persists, even given the less toy version of the theory. He continues the passage above:

The two assumptions of the previous paragraph are undoubtedly too crude, but the point is independent of them. Whether a notion is reasonably joint-carving --- enough to take part in special-science explanations --- has something to do with how it is based in the fundamental. So reference must have the right sort of basis in the fundamental if it's to be explanatory.

But it's just very difficult to say anything halfway reasonably simple about how any of this stuff arises from the fundamental. Things like pigs are just way too far removed from things like electrons. (And presumably, even electrons aren't fundamental anyway.)

More on this theme, and what I think we should say instead, tomorrow.

Sider on epistemic value and nature's joints

Ted Sider thinks that it's epistemically preferable to think in joint-carving terms; this is a way of better matching one's beliefs to the world. While something about that sounds right, I think that some of the the things he says must go too far. He writes, for example, that

[j]oint-carving thought does not have merely instrumental value. It is rather a constitutive aim of the practice of forming beliefs, as constitutive as the more commonly recognized aim of truth. (WtBotW p. 61)

I don't think this can be right. The idea of somebody forming beliefs without any kind of sensitivity or regard for whether they are true is incoherent; this is not so for someone who doesn't care whether her beliefs carve nature at the joints. Suppose one is charged with failing to carve at the joints with her beliefs, and replies flippantly --- so what? --- and maintains her previous beliefs? She might be criticizable on epistemic grounds, but her attitude is comprehensible, even if we do not approve of it. Compare the person who is charged with having false beliefs, and replies in the same way --- indifferently accepting the charge, and continuing to believe as before. This isn't just epistemically vicious; this runs counter to what it is to be a belief. In other words, a truth aim has a better claim to a constitutive connection to belief than a joint-carving aim does.

Here is another difference that should not be overlooked: some instances of non-joint-carving beliefs are absolutely correct to hold. Maybe they're not as good as their joint-carving cousins, but one needn't choose between them. You can believe that the emerald is green and that it is grue. In fact, that's exactly what you should do. And you shouldn't feel at all epistemically deficient for having the latter belief. Compare this to false beliefs: every false belief you have prevents you from having a true one.

Moore-paradoxes show a deep connection between belief and truth; there is a deep incoherence in the idea of accepting: "I believe that p, even though not-p." But there is no corresponding incoherence in "I believe that p, even though the terms in p do not carve at nature's joints."

Whatever epistemic value attaches to joint-carving, it is less central to belief than truth is.

Joint-Carving and Projectability

So this weird thing has been happening to me lately where I think about metaphysics. My current symptom is an attempted negotiation of Ted Sider's recent book, Writing the Book of the World. Ted's Big Idea is that there is objective structure to reality, and that this structure is really important for all kinds of reasons; I find the general picture a pretty attractive one, but I'm rather puzzled by some of his remarks on the applicability of structure to induction and confirmation.

Ted writes:

Which observations confirm a generalization 'all Fs are Gs'? A natural answer is the "Nicod principle": observations of Fs that are Gs confirm 'All Fs are Gs'. But suppose that an observation confirms any logical equivalent of any sentence that it confirms. Then, as Hempel pointed out, the observation of red roses confirms 'All ravens are black' (given the Nicod principle it confirms 'All nonblack things are nonravens', which is logically equivalent to 'All ravens are black'.) And as Goodman pointed out, Nicod's principle implies that observations of green emeralds before 3000 AD confirm 'All emeralds are grue' (sice green emeralds observed before 3000 AD are grue.) But anyone who believed that all emeralds are grue would expect emeralds observed after 3000 AD to be blue.
[This conclusion] can be avoided by restricting Nicod's principle in some way -- most crudely, to predicates that carve at the joints. Since 'is nonblack', 'is a nonraven', and 'grue' fail to carve at the joints, the restricted principle does not apply to generalizations containing them. In Goodman's terminology, only terms that carve at the joints are "projectable". (35)

I'm confused about this strategy. Ted says we can avoid the conclusion that nonblack nonravens confirm ravens' blackness because 'nonblack' and 'nonraven' don't carve at the natural joints. But 'nonblack' carves at exactly the same joint as 'black' does -- to push the metaphor only slightly further, it's the very same cut. So if 'nonblack' isn't joint-carving, and is therefore nonprojectable, then it looks like just the same would go for 'black', and mutatis mutandis for ravens and nonravens. So now it looks like I can't confirm that all ravens are black by observing black ravens. This isn't the result Ted wanted, surely.

So I'm worried that one of these things must be true:

1. The story quoted above about why red roses don't confirm that all ravens are black is wrong;
2. Black ravens don't confirm that all ravens are black; or 
3. The 'black' joint is natural, but the 'nonblack' joint isn't.

When I asked Carrie about this, she suggested that Ted might be intending something like (3) here. After all, she pointed out, there might be more of an objective sense in which all black things resemble each other than that in which all non-black things do. I guess the thought would be that the metaphor is breaking down here; 'joint-carving' isn't the right term. Maybe this is right, but I didn't see that Ted could go this way, since he doesn't want to take objective similarity as the most fundamental thing. He wants structure to be most fundamental, and to explain objective similarity in terms of structure.

I feel like I must be missing something obvious here, but I can't see what it is. Somebody help?