Thursday, November 18, 2010

Against Contrastivism

A conversation last night with Yuri and Andy helped me to get clearer on the argument I was trying to press in my last post. Here's the much more succinct way to make the point. It's an argument against forms of contextualism that put relevant alternatives into the proposition expressed by knowledge attributions.

Suppose I'm in a nonskeptical conversation, talking about Henry, who is standing in front of a barn. I have no reason to suspect any funny business, so I say, sensibly enough:

(K) Henry knows that he is standing in front of a barn.

Here are are three pretty plausible claims:

(1) If there isn't any funny business going on, my utterance of K is true.

(2) If it turns out that (unbeknownst to me) Henry is in fake barn country, (looking at the only real barn) my utterance of K is false.

(3) My sentence (K) expresses the same proposition, whether or not it turns out that Henry is in fake barn country.

If you think all of these things, then you can't think that the proposition I express builds in the relevant alternatives. Either the possibility that <the thing Henry is standing in front of is a fake barn> is relevant, or it's not, but it's his environment, not my context, that makes it relevant.

So if you want a Schaffer-style extra-argument-place approach to knowledge, this provides a reason not to let that argument place be one for a set of relevant alternatives. You might instead be a function from subject's situations to sets of relevant alternatives.

Yesterday I also included a parallel argument relying on pragmatic encroachment sorts of cases. I think it's a good argument too, but this one proceeds on less contentious premises.

Wednesday, November 17, 2010

Are 'epistemic standards' contrast classes?

Suppose you agree with Jonathan Schaffer that 'knows' takes an extra argument place, and that variation in what fills this slot explains the context-sensitivity of 'S-knows-that-p' attributions. Knowledge relates, say, a subject, a proposition, and, let's call it, the 'epistemic standard'. Nothing yet is assumed about what sort of thing that is. Schaffer thinks the epistemic standard is a contrast class, or, equivalently, a question. So "George knows he has hands" can express either of these three-place knowledge relations, depending on the context:

(1) K (George, <George has hands>, {<George has hands>, <George is not the sort of creature who has hands>, <George has lost his hands>})

(2) K (George, <George has hands>, {<George has hands>, <George is deceived by an evil demon into thinking he has hands>})

We could disambiguate in English, saying, "George knows he has hands rather than stumps", to get something like (1), or "George knows he has hands rather than being deceived by an evil demon into thinking he has hands" to get (2).

Identifying the epistemic standard with contrast classes does much of the work that a contextualist might legitimately seek -- for instance, it disambiguates the sentence above into a modest one and one inconsistent with skeptical intuitions -- but I think there might be a few reasons to prefer something different. Here are two related challenges to contrastivism that are not, I think, general challenges to the shifty variable approach.

Gettier cases. Suppose Henry's in fake barn country, but you and I don't have any reason to think that's so. (Neither does he.) I say to you, "Henry knows that he's looking at a barn." My sentence is ambiguous; what's the shifty epistemic standard? We can get an anti-skeptical reading with a contrast class of, e.g., barns and silos. But the antiskeptical reading in this case is very counterintuitive. To get the skeptical reading, which is the standard one, we need the contrast class to include fake barns. But given our situation, it's quite mysterious how the fake barn possibility got to be part of the semantic content of my sentence. (Compare the possible world in which everything seems exactly the same to all three of us, but Henry is in real barn country.)

Low-Attributor, High-Subject Bank Cases. Hannah and Sarah are desperate to get to the bank before Monday, and they have good but not great reason to think they can go tomorrow. You and I don't know and don't care how important it is to them; I say to you: "Hannah knows the bank will be open tomorrow." Here are two representative possible contrast classes: {<bank open tomorrow>, <bank not open Saturdays>}; {<bank open tomorrow>, <bank recently changed its policy and will be closed tomorrow>}. The latter is needed for the skeptical reading, which is the intuitive one; but what about me and my context could make it the case that this skeptical possibility is relevant? Again, compare the corresponding low-subject stakes version, which seems just the same to me.

Now I'm a good semantic externalist. So don't take me to be arguing that in each case, the intrinsic similarity entails sameness of semantic content. The argument can't go that directly. Nevertheless, in the relevant cases, it does look to me pretty strange that fake barns should appear in my content only if Henry happens to be in fake barn country, or that the policy-changing case is part of my content only if Hannah and Sarah's stakes are high. Intuitively, these features to which I'm blind are relevant to the truth of the knowledge attributions, but they are not relevant to their truth conditions.

Contrary to contrastivism, the subject is not irrelevant; the subject's practical and environmental features do play some role in determining what alternatives are relevant. This, to me, suggests that we might not want to put the relevant alternatives themselves into the semantics of my sentence. Don't make epistemic standards contrast classes; we can let the shifty epistemic standard be something else. Here's a modest suggestion: epistemic standards are functions from situations to contrast classes. A given standard tells you, for any situation the subject might be in, which possibilities are relevant. The speaker's context fixes the standard; the standard and the subject's situation fix the relevant alternatives. So speaker and subject are both 'relevant'.

Notice, by the way, that you don't have to go along with the encroachment stuff  to prefer this treatment to Schaffer's. The Gettier case provides, I think, a less contentious way of motivating just the same point. If you're one of those contextualists who is motivated in part by denying pragmatic encroachment, then you should think that no standard will deliver different alternatives for situations that differ only in stakes. (So you'll explain away intuitions about bank cases.) But unless you're also willing to explain away intuitions about Gettier cases, you should still have the standards be sensitive to the subject's environmental situation.

Sunday, November 14, 2010

Contextualism, Indexicalism, and Constrastivism

One of the questions I've been thinking about lately (unrelated to most of my recent blog posts) concerns the best linguistic implementation of contextualism about 'knows'. I've committed myself to contextualism in a couple of papers, but so far I have tried to avoid a commitment to any particular semantic treatment of 'knows'.

I take it the minimal commitment of contextualism starts with something like this: statements of the form 'S knows that p' can express different propositions in different conversational contexts. And to this, presumably, we add that the context-sensitivity of these sentences derives from the 'knows' -- it's not enough that various singular terms (the 'S's') or statements of propositions (the 'p's') are sometimes context-sensitive. But this leaves open some choices for what to do with 'knows'.

One choice is to treat 'knows' as an indexical, which refers to different relations in different conversational contexts. Call this "indexicalism." The other choice is not to treat 'knows' as an indexical, suggesting that something about it generates context-sensitivity in some other way. (It is unfortunate that 'non-indexical contextualism' has been used as a name for a different view, which is not a contextualist one by the standard of the previous paragraph.) Jonathan Schaffer has argued for a version of contextualism of this latter type. Schaffer's view, 'contrastivism,' is that 'knows' univocally picks out a three-place relation, relating a subject, a proposition, and a contrast class. The contrast class is often left implicit in sentences of the form 'S knows that p', and so it is filled in tacitly; since different contexts will suggest different ways of filling it in, 'S knows that p' ends up expressing different propositions in different contexts. (Schaffer uses his terms differently, too; he calls my indexicalism 'contextualism'.)

Schaffer's isn't the only way of being a contextualist who doesn't treat 'knows' as an indexical. Contrastivism is only one example of a view of this kind -- this kind of view needs a name! I really want to use 'non-indexical contextualist'... do y'all think I could reclaim that label? I think the view I'm describing is extremely well deserving of that name... Anyway, whatever you want to call it, there are lots of things besides contrast classes that might be arguments for 'knows'. I rather suspect that a view of this sort is correct, and one of my projects at the moment is to articulate such a view and explain why it might be preferable to any other form of contextualism.

So we have at least three different forms of contextualism on the table:

  1. Indexicalism. 'Knows' is an indexical; which epistemic relation it expresses depends on the conversational context. As far as I can tell, no one has actually seriously defended this view, even though it's often taken to be the standard claim of contextualism.

  2. Contrastivism. Jonathan Schaffer's view. 'Knows' univocally expresses a ternary relation Kspq, relating a speaker, a proposition, and a contrast class. This last is often filled in by the conversational context.

  3. Non-contrastivist extra-argument-place views. (I guess we need a name for this one too.) 'Knows' univocally expresses a ternary relation Kspx, where x is something other than a contrast class, and is often filled in by the conversational context. Until we get more specific, we might think of x as standing generically for an 'epistemic standard'.

I'm curious as to whether these exhaust the options for the contextualist. They do if the only ways that 'S knows p' can be relevantly context-sensitive are for 'knows' to be an indexical, or to take an extra argument place supplied by context. Anybody see any more choices here?

Friday, November 12, 2010

The Knowledge Norm of Practical Reasoning

For reasons exactly like the ones outlined in the previous post, these two claims are importantly distinct:

(1) If S knows p, then S can appropriately rely on p in practical reasoning.

(2) If S knows p, then p is warranted enough to justify S in phi-ing, for any phi.

I argued a couple of weeks ago that (1) is not strong enough to establish pragmatic encroachment. I suggested then that this was a problem for Fantl and McGrath; the discussion with Jeremy in the comments thread is part of what helped me to see the distinction between (1) and (2) more clearly. If their argument proceeded from (2), rather than (1), my argument doesn't apply. However, in light of the important distinction between these two claims linking knowledge and action -- I won't speak for anybody else, but this is a distinction I certainly hadn't been thinking clearly about before recently -- we should, if relying on claims like (2), proceed carefully, distinguishing arguments for (2) from arguments for (1).

I gave in my most recent post, linked at the top, an argument against a strictly weaker principle than (2). If that argument was right, then (2) is false. Let phi be an action that, for accidental reasons concerning the background environment, is only justified if S has some super-knowledge access to p. The example from that post was, let phi be the assertion that p, and let the background be such that S has promised, in a morally weighty way, not to assert p unless S knows that she knows that she is absolutely certain that p; let p be known, but the higher condition not be met. Then S is not justified in phi-ing, under the circumstances, even though she knows p, and even though, were p better warranted, she would be.

But maybe that argument went a little too quick. For maybe it's question-begging to assume, as I did, that one can know p without being in the super-epistemic position, under the circumstances described. Maybe the act of promising collapses that distinction. If so, then my argument against (2) can be resisted. Indeed, it's sort of the point of (2) that the 'standards' for knowledge raise to as high a level as one might need in any given circumstance.

But -- and here's the main point of this post -- one can retain (1) without collapsing that distinction. That's another respect in which (1) is interestingly different from (2).

Assertability and Norms of Assertion

Here's a crazy thesis that nobody holds:

(1) If S knows that p, then S is permitted to assert that p.

There are boring counterexamples to (1). For instance, there are cases in which I am morally forbidden from asserting things that I know. This, of course, shows nothing interesting about the relationship between knowledge and assertion. So to capture the content of the interesting claim in the neighborhood, we move from (1) to something subtler and less crazy; maybe something like one of these:

(2) If S knows that p, then no epistemic shortcoming in S can explain why asserting that p would be inappropriate.

(3) If S knows that p, then S is in a strong enough epistemic position to assert that p.

(4) If S knows that p, then improving S's epistemic position won't put S in a position to assert p.

Maybe (2)-(4) are equivalent to one another; I'm not sure. They do a better job than (1) does at rendering certain kinds of cases of knowledge without assertability irrelevant. But they, too, are subject to conclusive refutation in a way orthogonal to the knowledge norm of assertion. My argument against (1) concerned cases in which I'm morally prohibited from asserting something, even though I know it -- maybe telling the Nazis where the Jews are hiding or something like that. But there are also cases in which I'm morally prohibited from asserting something, even though I know it, where a failure in my epistemic position plays a role in explaining the prohibition. There are boring cases like this. For instance, suppose that I've made a promise to assert that p only if I know that q. (Maybe promising by itself is insufficient for the relevant duties; stipulate that we're talking about a promise that carries serious moral weight.) Now suppose I know p, but don't know q. It's impermissible to assert that p, even though I know p -- and even though a deficiency in my epistemic position plays a role in explaining why p is unassertable. These cases, too, show that (2)-(4) don't get to the heart of the matter.

And it won't help to relativize the claims about strength of position to p, either. That is, these attempts at the knowledge norm face the same problem:

(5) If S knows that p, then S is in a strong enough epistemic position with respect to p to assert that p.

(6) If S knows that p, then improving S's epistemic position with respect to p won't put S in a position to assert p.

(7) If S knows that p, then p is, for S, warranted enough to justify S in asserting that p.

For take the special case of the sort of example given above where q is a proposition about S's epistemic position with respect to p. For instance, suppose I've promised not to assert p unless this condition is met: I know that I know that I'm absolutely certain that p. Suppose also that I know p, but don't know that I know that I'm absolutely certain that p. Under the circumstances, p is unassertable, because my epistemic position with respect to p isn't strong enough. But that doesn't show us anything interesting about the knowledge norm of assertion, if the latter is meant to be understood as showing something interesting distinctively about assertion.

What the knowledge norm of assertion suggests is that there's a special way that assertions can fail qua assertions. It says that if S knows p, then an assertion that p doesn't fail in this particular way. It doesn't provide any sufficient conditions for not failing in some other way, even when you build in all of these conditions about S's epistemic position.

Therefore, none of (1)-(7) are closely related to:

(Norm) Knowledge is the constitutive norm of assertion.

This post has gone on long enough for now, but I'll close by just asserting that many attempts to argue against the knowledge norm of assertion really look like arguments against some or all of (1)-(7); this is a mistake. I've argued that (1)-(7) are definitely false, for boring reasons that don't have anything to do with assertion in particular. If all you have is a case along with intuitions about what is known and what is unassertable, and why it's unassertable or under what circumstances that unassertability would be rectified, then you don't have anything strong enough to speak directly to (Norm). To evaluate (Norm) via the method of cases, you'd need to have intuitions about whether the assertion suffers from a particular kind of failure qua assertion. These, I think, we rarely have at any kind of pretheoretic level.

Thursday, October 28, 2010

Knowledge Norms and Pragmatic Encroachment

I'm thinking a bit more today about the point I made in a post yesterday about the use of intuitions about cases to evaluate knowledge norms. That point was basically that facts about whether S knows p and whether S is well-enough situated epistemically in order appropriately to X don't by themselves say anything about the knowledge norm of practical reasoning; S may know p without X's being appropriate just by virtue of p's not being a good enough reason to X. Yesterday I used this observation to rebut a certain kind of argument against knowledge norms.

I now think that, in addition to that use, this observation undercuts certain implications sometimes drawn from knowledge norms. In particular, I think it points to a lacuna in one of the central arguments of Fantl and McGrath's defense of pragmatic encroachment. I think this is a pretty fair reconstruction of their §4.3:

  1. KJ: If you know that p, then p is warranted enough to justify you in phi-ing, for any phi.

  2. Consider some low-stakes action, X, for which LOW has q as a sufficient reason; LOW can appropriately perform X. (Their example: Matt knows the train is a local; this justifies his boarding it.)

  3. There is a possible counterpart of LOW in the same epistemic position but with higher stakes, HIGH, such that HIGH cannot appropriately perform X. (Their example: Jeremy really needs to get off at a local stop; the stakes are too high for him to risk boarding.)

  4. So q is not well-enough warranted to justify X in phi-ing.

  5. So HIGH does not know q.

  6. So two subjects in the same epistemic position can differ with respect to knowledge of q.

  7. So purism is false.

(For maximum faithfulness to F&M's broader intentions, we should understand this entire argument, including its conclusion, as being offered under the conditional assumption that fallibilism is true -- that it's possible to know that p, even though there is some epistemic possibility that not-p.)

I'm concerned with the move from (3) to (4). It has pretty much the same form as the arguments sketched above, except that it's holding different bits fixed. Jessica Brown argued from what she saw as intuitive verdicts about knowledge and appropriate action against the knowledge norm; Fantl and McGrath argue from intuitive verdicts about appropriate action and the principle of the knowledge norm against the knowledge verdict Brown found intuitive. My argument shows the flaw in both of these arguments. (In a sense, they are instances of the same argument, run in different directions.)

The move from (3) to (4) relies, like Brown's surgeon case argument, on the assumption that the knowledge of q, the non-actionability of X, and the knowledge norm are incompatible. But as I've shown, they're not. They're incompatible only on the assumption that q is, if possessed as a reason, a good enough reason to X. And there just aren't obvious intuitive verdicts about facts like these; neither are there clear theories that dictate which claims like these to accept. It's obvious enough whether S knows q, and whether S would be justified in Xing -- but whether q itself is well-enough justified to be among the reasons S has for Xing is an esoteric question on which naive intuitions are silent.

Everybody who accepts (2) and (3) has to think there's some important difference that derives from a change in the stakes that bears on actionability. But you can think this without giving up on KJ, fallibilism, or purism, if you want to. You can say that what propositions are good enough reasons to X depends in part on the stakes. That is: whether p is known is stakes-independent; so too is whether p is warranted enough to be a reason for phi-ing, for any phi. What varies by stakes is whether p, supposing that it is a reason, is by itself a good enough reason to phi. When the stakes are high, p, though still genuinely a reason, isn't a good enough reason. In lower stakes, p is a good enough reason. Insensitive knowledge; insensitive reasons for action; sensitive needs of actions for reasons.

This does look to me like a significant and substantive gap in F&M's argument. I'm generally pretty sympathetic to F&M-style views -- I'm a different sort of contextualist than those who are motivated by 'intellectualism' -- but this does look to me to be a potentially promising avenue for resisting pragmatic encroachment from F&M-style arguments.

It will not obviously help, however, with the knowledge intuitions about bank cases and the like. Lots of pragmatic encroachment people seem to be turning their emphasis away from these cases recently, in favor of broader theoretical arguments. Certainly, this seems to be one of F&M's aims. I rather suspect, though, that the pragmatic encroachment theorist may end up needing to rely on judgements about cases more than they think. (I don't know that that's a problem.)

Wednesday, October 27, 2010

Knowledge Norms and Intuitions about Cases

Here's a boring thought experiment that doesn't demonstrate anything.
Smith burgled the house last night; Detective Stanley is investigating the crime scene. He acquires evidence sufficient for knowledge that the burglar came in through the window, but finds very little evidence about whether it was Smith or someone else who committed the crime.

Here are two intuitive verdicts that aren't in any tension at all:

  1. Stanley knows that the burglar came in through the window.

  2. Stanley would need to have more evidence in order for it to be appropriate for him to arrest Smith.

Everybody can accept these obvious claims. In particular, these obvious claims are in no tension with the knowledge norm of practical reasoning, which claims that p can be an appropriate reason for action for S if and only if S knows that p. It would be an anemic objection to the knowledge norm to point out that Stanley knows that the burglar used the window, but needs more evidence in order for it to be appropriate to arrest Smith. That the burglar used the window just isn't a strong enough reason to arrest Smith, so this case doesn't tell us anything about what is and is not a reason. So it doesn't tell us anything about knowledge norms.

The moral of the story is that claims about who knows what, and about what actions are inappropriate, are in general insufficient to refute the knowledge norm of practical reasoning. (So, mutatis mutandis, for the knowledge norm of assertion.)

When you look at the case given above, this moral is really obvious. But sometimes, I think, it's neglected. Jessica Brown, for instance, argues against the knowledge norm of practical reasoning by citing this case:
A student is spending the day shadowing a surgeon. In the morning he observes her in clinic examining patient A who has a diseased left kidney. The decision is taken to remove it that afternoon. Later, the student observes the surgeon in theatre where patient A is lying anaesthetised on the operating table. The operation hasn’t started as the surgeon is consulting the patient’s notes. The student is puzzled and asks one of the nurses what’s going on:

Student: I don’t understand. Why is she looking at the patient’s records? She was in clinic with the patient this morning. Doesn’t she even know which kidney it is? Nurse: Of course, she knows which kidney it is. But, imagine what it would be like if she removed the wrong kidney. She shouldn't operate before checking the patient’s records.

We have, as before, a pair of intuitive verdicts: one attributing knowledge, and another denying appropriateness of action. Brown considers this to be a counterexample to the knowledge norm of practical reasoning, but the case of the burglar shows that this cannot not enough. Just as the burglar argument was transparently invalid, because the burglar's use of the window wouldn't be sufficient reason for arresting Smith, Brown's argument is valid only on the assumption that the disease in the left kidney would be a sufficient reason for operating without checking the charts. But Brown has given us no reason to think that is so. It's entirely open to the defender of the knowledge norm to argue that knowledge of p is sufficient for p to be a reason, but that in this case, p isn't a good enough reason for action.

This strategy is always available. I think this shows that trading in intuitions about who knows what, and who ought to do what, is not a helpful strategy for evaluating knowledge norms.

Modals and Modal Epistemology

I've just uploaded a new draft of my paper on modals and modal epistemology. (I posted an earlier draft a few weeks ago.) If anyone's interested, it's here:

Modals and Modal Epistemology

Comments are extremely welcome. I hope to submit it soon, so if you wanted to provide feedback in the next week or so, you'd be a total hero. But I'm interested to hear thoughts later, too, of course.

Tuesday, October 19, 2010

Merely verbal disputes are rare

Pretty much everybody, I think, agrees that some disputes are merely verbal. For example, I may overhear someone say "Derek has big hair," think of my colleague Derek Ball, and retort, "you're wrong, Derek has short hair." If it turns out that my interlocutor was referring not to Derek Ball but to Derek Parfit, then our dispute was merely verbal. She and I were talking past one another; "Derek" in her mouth meant something different than did "Derek" in mine, and it turned out we were both right in our respective claims about each "Derek." So much is pretty uncontroversial, I think. When one party says sentence S, expressing proposition p, and another party wrongly takes q to be expressed, and takes himself to disagree in arguing against q, we have a merely verbal dispute.

In some recent work, Dave Chalmers argues that the phenomenon of merely verbal disputes is broader than the example above suggests. He rejects the necessity direction of
A dispute over S is verbal iff the parties use S to express distinct propositions p and q (respectively) and the parties do not disagree over the truth of p or of ¬q.

His argument appears to be one involving intuitive counterexamples. I'm not convinced.

Tuesday, October 05, 2010

Imagination and Belief in a "Single Code"?

A robust and celebrated fact is that imagining that p is often in various respects similar to believing that p. For example, when I imagine, say in the context of engaging with a fiction, that a great injustice has been committed, I feel angry in a way similar to the way I'd feel if I believed that a great injustice has been committed.

Shaun Nichols attempts to offer an explanation for this and other similarities in his paper "Imagining and Believing: The Promise of a Single Code". I'm having a pretty hard time seeing how his explanation is supposed to work.

The explanation Nichols offers, citing his previous work with Steve Stich, is that imagination and belief are distinct propositional attitudes with distinct functional roles, but that the propositional contents of each are given by representations in the "same code". What exactly does this mean?

Wednesday, September 29, 2010

Belief and Desire as Commitment

According to a common view, beliefs suffer a coherence constraint that desires do not. If I believe that p, then I'm very unlikely, at the very same time, to believe that not-p -- and if I do, that's a clear rational failing. But desiring various contradictory things is commonplace.

I don't want to dispute that the English statement of the common view just given can often express a truth. But I think it's a mistake to infer from this that there's something interestingly different between the natures of belief and desire. The words 'belief' and 'desire' are used loosely to refer to a few different kinds of things. And the ones that are of most interest in a lot of philosophy, I think, are structurally much more similar than the common view would lead one to think.

Tuesday, September 28, 2010

Particular Beliefs and Belief-Desire Psychology

Let us suppose that Dmitri knows how to sing the "Il balen" cadenza from Verdi's Il Trovatore.

There's a debate about whether Dmitri's knowing how to sing the cadenza amounts to knowing some proposition. According to 'intellectualists', knowing how to X just is (to an approximation), knowing, for some w, that w is a way to X. I don't mean to weigh in on that debate just now, but one of the moves in it is relevant for an issue concerning imagination, which is my current research topic du jour. The move is, on its face, an argument against the thesis that knowing how is knowing that -- it argues that in some cases in which know-how is clearly present, the relevant know-that is not present, because the requisite beliefs are absent or even disbelieved. For example, Dmitri may, consistent with his knowing how to sing the cadenza, have entirely erroneous beliefs about how he does it. Maybe he thinks that he clenches his abdominal muscles, when what he really does is expand his ribcage. He thinks that he opens his mouth widely, but what he actually does is lift his soft palate. The way he sings the cadenza is by expanding his ribcage and lifting his soft palate, but he doesn't know that, because he doesn't believe it. Charles Wallace offers a version of this argument. (This was brought to my attention in a forthcoming paper by my new colleague Ephraim Glick.)

Sunday, September 26, 2010

Inference in Imagination, Belief, and Desire

Shaun Nichols writes:
In addition to a pretense box, Stich and I propose a mechanism that supplies the pretense box with representations that initiate or embellish an episode of pretense, the “Script Elaborator”. This is required to explain the bizarre and creative elements that are evident in much pretend play. However, there are also much more staid and predictable elaborations in pretend play. This too is well illustrated by Leslie’s experiment. Virtually all of the children in his experiment responded the same way when asked to point to the “empty cup”. How are these orderly patterns to be explained? In everyday life when we acquire new beliefs, we routinely draw inferences and update our beliefs. No one knows how this process works, but no one disputes that it does work. There must be some set of mechanisms subserving inference and updating, and we can simply use another functional grouping to collect these mechanisms under the heading “Inference Mechanisms”. Now, to explain the orderly responses of the children in Leslie’s experiment, we propose that the representations in the pretense box are processed by the same inference mechanisms that operate over real beliefs. Of course, to draw these inferences the child must be able to use real world knowledge about the effects of gravity and so forth, and so Stich and I also suppose that the inferences the child makes during pretense can somehow draw on the child’s beliefs.

This is, I think, a fairly typical statement of one important respect in which belief is often said to be similar to imagination: each is subject to the same inference mechanisms. Nichols includes this chart:


Notice the 'inference mechanisms' that act on beliefs and imaginings alike.

Now I can see well enough that pretense and belief inferences tend to go in the same way. If I know full well that p only if q, and believe p, I'll often come to infer to a belief that q, just as, if I imagine p, I'll often come to infer to imagine q. (Modulo various familiar complications: sometimes I give up the previous belief, etc.) But doesn't just the same thing happen with desire? If I desire that p, and know full well that p only if q, I'll very often, through a very ordinary sort of means-end reasoning, come to desire that q, modulo various familiar complications like the possibility that I'll stop desiring p.

Take a background situation where I know that nothing funny is going on with the cups; gravity is normal, the water is liquid, etc.

Suppose I believe the cup had water in it and has been turned over. Then I'll believe that the cup is now empty.

Suppose I imagine or pretend that the cup had water in it and has been turned over. Then I'll imagine or pretend that the cup is now empty.

Suppose I desire that the cup had water in it and has now been turned over. Then I'll desire that the cup is now empty.

This suggests to me that the similarities between imagination and belief, in contrast with desire, are exaggerated by, e.g., the diagram above. Those inference mechanisms apply to desires just as well as to beliefs and pretenses. Are there similarities in inference mechanisms that distinguish beliefs and pretenses/imaginings from propositional attitudes more generally?

Friday, September 24, 2010

New draft paper on modals and modal epistemology

I've just completed a draft of a new paper on modals and modal epistemology, developing some of the ideas in my last few blog posts, and engaging with Timothy Williamson's discussion of counterfactuals and modal epistemology. Here's the abstract:
Modals and Modal Epistemology

Abstract. I distinguish (§§1-2) two projects in modal epistemology, and suggest (§3) that Timothy Williamson’s treatment of modal epistemology, relating truths of modality to counterfactual conditionals, is best understood as a way of addressing the mystery of why we should have developed cognitive access to facts of metaphysical modality. I offer (§4) a reconstruction of his argument, so interpreted. I compare Williamson’s counterfactual-based approach to metaphysical modality with a treatment in terms of quotidian modals (§§5-6), relating each to the dominant linguistic treatments of modals and conditionals (§§7-8). The insights offered by these linguistic treatments will emphasize the similarity of the counterfactual approach with the quotidian modals approach—in particular, they will demonstrate that the counterfactuals approach does not enjoy the advantage over the latter that Williamson claims for it. The ultimate lesson to be drawn (§9) is that there is a respect in which investigation into metaphysical modality is sui generis; but this is not a respect that renders modal epistemology implausibly mysterious.

The draft is online here. Comments are definitely very welcome -- feel free to email me, or leave a comment to this blog post, or get in touch with me in whatever other way seems like a good idea.

Sunday, September 19, 2010

Williamson on modal epistemology and counterfactuals

This post is an exercise in Williamson exegesis. I'm looking primarily at chapter five -- the modal epistemology chapter -- of The Philosophy of Philosophy. (That chapter substantially overlaps a couple of earlier papers as well.) As many readers will know, Williamson emphasises the equivalence of claims of metaphysical modality with particular counterfactuals (such as the ones discussed in my recent post here), and suggests, therefore, that our ordinary imagination-based capacity for the evaluation of counterfactual conditionals brings along with it a capacity for knowledge of metaphysical modality. As Williamson says, "the epistemology of metaphysical thinking is tantamount to a special case of the epistemology of counterfactual thinking."

There are important interpretive questions that are too easily overlooked. The question I'm after right now is just: what in particular is Williamson trying to accomplish in this material? I think that many people are not always clear about this question. (Williamson is one of these people.)

One candidate project is to answer what I'll call the 'how' question:

How do we have modal knowledge?

A possible answer to the how question suggested by Williamson's work, which emphasizes the equivalence of modal claims with certain counterfactuals, is that we acquire modal knowledge by coming to have counterfactual knowledge, and exploiting the connection between counterfactual truths and modal truths. I think understanding Williamson's project in this way would be a mistake.

Wednesday, September 08, 2010

Counterfactuals and Modals

I like the approach to counterfactuals that treats them as modals. The sentence 'if A were the case, C would be the case' says that, out of some restricted class of possibilities, all the A possibilities are C possibilities. Which restricted class is in play is of course in part a context-sensitive matter. The relevant class of possibilities is relevant for other modal language, too. I've argued, controversially, that this is the case for 'knows'. But there are much less contentious cases, too. Consider bare modals like 'might' and 'must'; these definitely take context-sensitive domains, and those domains look to play central roles in the interpretation of counterfactual conditionals, too.

There is a kind of conflict between sentences like these, uttered back to back in a given conversational context:

(1) If he were to break thorough his chains, he would save the girl.

(2) He couldn't possibly break through his chains.

The 'kind of conflict' here isn't necessarily a matter of semantic inconsistency. (The approach to modals and counterfactuals I have in mind has the second entailing the first -- if there's no possibility of his breaking his chains, then, trivially, all possibilities in which he breaks through his chains are ones in which he kills his captors.) It's rather something like a pragmatic tension. The 'couldn't possibly' claim requires the modal base to be devoid of cases in which he breaks through his chains; such a base renders the counterfactual trivial -- so the counterfactual strongly prefers a context in which there are some chain-breaking possibilities among the modal base. (Compare: "There's nothing in this bottle." "All the air in the bottle is musty.")

Given this connection between bare modals and counterfactual conditionals, it's pretty straightforward to see that certain equivalences will hold as well. In particular, these two sentences will, in any given context, have the same truth value:

(3) He can't phi.

(4) If he were to phi, then p and not-p.

Thursday, September 02, 2010

Varieties of Modality

We all know that metaphysical possibility isn't the same thing as physical possibility, or other 'restricted' notions.

It is sometimes suggested that the modifiers ‘metaphysically’, ‘physically’, ‘epistemically’, etc., in phrases like ‘metaphysically possible’ act as restrictors on the more general, univocal, property of possibility. (Compare: someone can be surprisingly wealthy, unjustly wealthy, or extremely wealthy — these are all just more specific ways of being wealthy.) On this model, there is a property — possibility — and modal language attributes it, often specifying the way in which the relevant situation is said to be possible. When we say that it is physically possible that a man should run the 100m-dash in 9.50 seconds, we say that this achievement is among a particular subset of the possible: the physically possible.

This isn't exactly how I think about possibility language, but it's not too far off.

One question raised by this approach concerns just what the unrestricted modality includes. It’s clear enough that the physically possible is a restriction on the metaphysically possible. One might continue to suggest that the metaphysically possible is a subset of the conceptual or logically possible—and perhaps further into various logically impossible ‘possibilities’. Or one might somewhere draw the line. George Bealer, in his contribute to the Gendler & Hawthorne Conceivability and Possibility anthology, draws the line at the metaphysically possible. He writes:
[S]ome people insist on distinguishing logical possibility and metaphysical possibility and so are led to the following: p is logically possible iff p is merely consistent with the laws of logic (i.e., not ruled out by logic alone). This usage, however, invites confusion. There are many logically consistent sentences that express obvious impossibilities (e.g., ‘Bachelors are necessarily women’, ‘Triangles are necessarily circles’, ‘Water contains no hydrogen’). If you buy into calling mere logical consistency a kind of possibility, why not keep going? For example: p is ‘sententially possible’ iff p is consistent with the laws of sentential logic. Then, since ‘Everything is both F and not F’ is not ruled out by sentential logic (quantifier logic is what rules it out), would it be possible in some sense (i.e., sententially possible) that everything is both F and not F?! Certainly not my ear! (78-79)

I don't think this comprises a very good argument, for at least two reasons.

First, the logical structure of the argument for drawing the line at metaphysical possibility is suspect. It follows a particular erroneous form of a slippery slope argument: if you permit X (which doesn’t seem too bad), then what’s to stop you from going on to permit Y (which seems terrible)? The difference in felt terribleness, if there is one, would provide just the needed traction between X and Y in order to avoid the slip. Remember that drawing the line at metaphysical possibility represents a substantive choice; one might try draw it even more narrowly — at physical possibility, say. Imagine a philosopher who refuses to countenance those ‘metaphysical possibilities’ which violate the laws of physics; he will insist that they’re in no sense possible. Against someone like Bealer, who believes in such physically impossible possibilities, he might offer just the same retort: “if you buy into calling mere metaphysical consistency a kind of possibility, then why not keep going?” If there is reason to countenance metaphysical possibilities—and I agree with Bealer that there is—then presumably, we will justify it by reference to the useful work to which thinking about metaphysical modality can be put. But for all Bealer has said, it may well be that further conceptual or logical possibilities can be put to similar work. (This seems to me very plausible.)

The second reason to be concerned with Bealer’s argument is that he makes an insufficient case for the undesirability of the bottom of his slippery slope. Bealer apparently finds the suggestion that there is a sense in which this contradiction is possible implausible. He doesn’t say why, but the invocation of how it strikes his ear suggests it may be based in a linguistic intuition; it just sounds terrible, perhaps, to say that there’s a sense in which it is possible that everything is both F and not F. But that there is some sense in which it possible does not, of course, imply that it’s a very interesting sense, or one that ordinary speakers are used to thinking about. Bealer ostends a notion of ‘sentential possibility’, abstracting away from any use to which thinking about it might be put. It shouldn’t come as any surprise, then, that, so presented, we shouldn’t have any interest in thinking about such ‘possibilities’. That doesn’t mean they’re not there, ready for us to take them up if and when the course of inquiry demands it. (Again, a philosopher who thought of physical possibility the way Bealer feels about metaphysical possibility might respond just the same way Bealer does, in response to what is conventionally recognized as the physically impossible metaphysically possible. "It's just not possible in any sense for humans to travel faster than light." Actually, I suspect that most people who haven't studied metaphysics are likely to respond this way.)

Tuesday, August 31, 2010

Draft monograph on rationalism

As you may have noticed, I haven't been posting here much lately. That's for a couple of reasons. One is that, as many of you will know, my personal life has lately been very exciting. Carrie Jenkins and I are recently engaged to be married. So that's pretty awesome. It also means I'm spending a good chunk of my time working on wedding planning.

The other reason I haven't been posting much is that, for all of this summer, and much of the past year, I've been, when focused on philosophy, focused on work on a co-authored book monograph with Benjamin Jarvis. That's been on a relatively grand scale, and didn't lend itself well to blogging. However, we now have a draft of a book monograph, and we're ready to give it a limited distribution to philosophers who might have comments and suggestions for us.

Our book is tentatively titled Rational Thinking: Philosophical and Quotidian. It offers a theory of mental content, a characterization of the relation between rationality and apriority, and a treatment of philosophical methodology. It is descended in fairly direct ways from the work we've done in our two previous co-authored papers, here and here.

If you're interested in having a look, email me and I'll send you the pdf. I'm placing a detailed table of contents below the fold, to better indicate the sort of topics we're covering.

Maybe now that we've gotten the manuscript to this stage, I'll find myself blogging on philosophy more often. I have an idea for a paper about the relation between modal epistemology and linguistic treatments of modality.

UPDATE 15 JULY 2011: new TOC and downloadable new draft available here. Old TOC below.

Friday, April 16, 2010

In Defense of a Kripkean Dogma

In Defense of a Kripkean Dogma, with Ishani Maitra and Brain Weatherson, penultimate draft: 22 February, 2010, forthcoming in Philosophy and Phenomenological Research.
In “Against Arguments from Reference”, Ron Mallon, Edouard Machery, Shaun Nichols, and Stephen Stich (hereafter, MMNS) argue that recent experiments concerning reference undermine various philosophical arguments that presuppose the correctness of the causal-historical theory of reference. We will argue three things in reply. First, the experiments in question—concerning Kripke’s Gödel/Schmidt example—don’t really speak to the dispute between descriptivism and the causal-historical theory; though the two theories are empirically testable, we need to look at quite different data than MMNS do to decide between them. Second, the Gödel/Schmidt example plays a different, and much smaller, role in Kripke’s argument for the causal-historical theory than MMNS assume. Finally, and relatedly, even if Kripke is wrong about the Gödel/Schmidt example—indeed, even if the causal-historical theory is not the correct theory of names for some human languages—that does not, contrary to MMNS’s claim, undermine uses of the causal-historical theory in philosophical research projects.

Experimental Philosophy and Apriority

Experimental Philosophy and Apriority, Draft of 15 April, 2010

One of the more visible recent developments in philosophical methodology is the experimental philosophy movement. On its surface, the experimentalist challenge looks like a dramatic threat to the apriority of philosophy; ‘experimentalist’ is nearly antonymic with ‘aprioristic’. This appearance, I suggest, is misleading; the experimentalist critique is entirely unrelated to questions about the apriority of philosophical investigation. There are many reasons to resist the skeptical conclusions of negative experimental philosophers; but even if they are granted—even if the experimentalists are right to claim that we must do much more careful laboratory work in order legitimately to be confident in our philosophical judgments—the apriority of philosophy is unimpugned. The kinds of scientific investigation that experimental philosophers argue to be necessary involve merely enabling sensory experiences. Although they are not enabling in the sense of permitting concept acquisition, they are enabling in another epistemically significant way that is also consistent with the apriority of philosophy.

Presupposition and 'Knows' Contextualism

In a recent paper in Mind, Michael Blome-Tillmann defends a form of 'knows' contextualism that is broadly Lewisean. His project is, in its broad forms, very similar to that in one of my forthcoming papers. In my paper, I argue that Lewis's particular suggested rules for proper ignoring are inessential to the central contextualist insight, which is that one can model 'knows' in a way similar to context-sensitive quantifier domains, and that maybe he should have just rested happily with the latter, rather than trying to articulate all the relevant rules. Blome-Tillmann agrees with me that Lewis's particular rules are inessential to his broader project, but, unlike me, he goes on to attempt the ambitious task of articulating rules that will do the relevant work. So rather than rest content with the main contextualist point, as I do, Blome-Tillmann argues for a different solution than Lewis's to Lewis's original, more ambitious project. The suggestion is to replace the Lewisean 'Rule of Attention' with a 'Rule of Presupposition':
(RP) If w is compatible with the speakers' pragmatic presuppositions in C, then w cannot be properly ignored in C.

Pragmatic presuppositions here are meant to be understood in the Stalnakerian way. The basic idea is that there are different ways to attend to skeptical possibilities; if you just listen to a presentation of them but continue to presuppose them not to obtain, then you can still 'properly ignore' them. But if our common ground shifts so as to include those possibilities, then they are no longer properly ignored.

It may well be that the Rule of Presupposition does a better job with cases than does the original Rule of Attention on the whole. But it does worse in at least some cases. Consider some expression PHI, used to pick out an individual, whose felicity requires that some p be presupposed. For example, the expression "the man sitting at the table" requires it to be common ground that there is a uniquely salient man sitting at a uniquely salient table. Now consider a sentence of the form "PHI does not know q", where p obviously entails q--e.g., "the man sitting at the table does not know that there is a table."

Intuitively (once we've bought into contextualism), some such sentences can both be felicitous and vary in truth from context to context, even when discussing the same subject and proposition. For example, someone in a skeptical context might say "the man sitting at the table does not know that there is a table" truly, even as, in another, nonskeptical context, someone might say "the man sitting at the table does know that there is a table" and speak truly. This is the sort of result contextualists want to capture. But I don't think Blome-Tillmann can capture it. Anybody who utters that sentence felicitously is in a context in which it is presupposed that there is a table. (The previous paragraph gave a recipe for coming up with lots of similar examples.) Blome-Tillman's Rule of Presupposition, then, cannot explain the difference between the skeptical context and the nonskeptical one with respect to whether non-table-including possibilities are properly ignored. And none of Lewis's other rules, besides the Attention one that Blome-Tillman rejects, looks well-suited to do the job either.

So I don't think that presupposition can do the work Blome-Tillman wants it to do in articulating what possibilities are properly ignored. I still think it's best not to get too worked up about these details, and rest content with the contextualist insight.

Friday, March 12, 2010

Conditional knowledge attributions

I'm going to be discussing an argument that I know Jason Stanley to have given, but I'm away from my copy of his book at the moment, so I can't cite it properly, or check and see who else has discussed it (or even whether it's original to Jason). I'll follow up if citation protocol ends up demanding it.

Here's a naive argument against 'knows' contextualism. (This isn't the Stanley argument I want to discuss; it's part of the set-up for it.) Assume contextualism. Now suppose you're in a nonskeptical context, and I'm in a skeptical one, and we're both talking about me and the proposition that p, a proposition with which I stand in a pretty strong epistemic relation -- one strong enough for your non-skeptical 'knows', but not for my skeptical 'knows'. You say: "Jonathan knows p." Now, according to this naive objection, I'm forced to say this:

(1) I don't know that p, but what you said was true.

This sounds like a crazy thing to say, under the circumstances, but it looks like contextualism predicts that it should be fine.

Of course, contextualism doesn't predict that (1) should be fine; the naive objection is naive. Contextualism avoids the felicity of this utterance by observing that it won't be assertable for me. What you said entails p (even your nonskeptical 'knows' is factive). Since I'm not in a context in which "I know that what you said is true" is true, I therefore can't assert that what you said is true. Indeed, (1) is Moore-paradoxical, or near enough, since it straightforwardly and transparently entails "I don't know that p, but p."

So there's a naive objection to contextualism and a good response on the contextualist's behalf. But Jason Stanley thinks the game isn't over yet, for he has a tweak on the objection to make it less naive in a way that he thinks will avoid the response. Take the same set-up as before; you're in a non-skeptical context and you say "Jonathan knows p," and I'm in a skeptical context where "I know p" is false. Now, Jason asks, why shouldn't I give this sentence?

(2) I don't know that p, but if p is true, then what you said is true.

Here, the second conjunct doesn't entail that p, so the sentence isn't Moore-paradoxical. Insofar as (2) also sounds crazy, we have a version of the objection that isn't susceptible to the quick response given above. (Does (2) sound crazy? Is it a natural enough sentence to generate clear intuitions? I don't know. Let's grant for the purpose of argument that it sucks to have to render this sentence assertible.) The contextualist, I contend, is not committed to the assertibility of (2). Although (2) is not Moore-paradoxical, because the second conjunct does not entail p, its infelicity can still be explained as a violation of the knowledge norm of assertion, since it's second conjunct will, in the relevant cases, be unknown.

Wednesday, March 10, 2010

'Significant Possibilities' and Concessive Knowledge Attributions

Suppose you think that it's possible to know that p, even though your epistemic position vis-a-vis p is weak enough for 'it might be that not-p', in its epistemic reading, to be true. I don't really see why you'd want to think this myself, but I guess some people think that (a) this is a good reading of 'fallibilism' and (b) fallibilism is true. If you think this, then you face the problem to explain the infelicity of concessive knowledge attributions. Why's it sound so bad to say "I know that p but p might be false"?

The obvious explanation is that it's a contradiction: according to standard epistemic modal logic, 'might', in its epistemic reading, is just the dual of 'know'. But the fallibilist of this stripe has closed off that response. What's he say instead? Dougherty and Rysiew propose a pragmatic line: "p might be false," they say, implicates but does not entail that there is a significant chance of not-p. And while a chance of not-p is consistent with knowledge that p, a significant chance of not-p is not. Fantl and McGrath supplement the story by suggesting that the significance of various chances can be a stakes-sensitive matter; the same possibility, with the same likelihood, can be significant if the stakes are high, and insignificant if the stakes are low.

Now I get nervous when Gricean pragmatic stories are asked to do work like this. Too often, the data don't generalize the right ways. Here's one problem: the pragmatic effect doesn't seem appropriately cancelable. Consider:

It's possible that it will rain today, but I know it won't rain today.

The badness of this sentence is explained, on the view in question, by suggesting that the first conjunct pragmatically implicates that there is a significant chance that it will rain today. It predicts, then, that if we cancel the implication, we're left with felicity. But this prediction is not borne out; this is still bad:

It's possible that it will rain today, but there's no significant chance that it will rain today, so I know it won't rain today.

Also, there's a point that Derek Ball raised in Jason Stanley's seminar last week, inspired by Seth Yalcin: the infelicity of concessive knowledge attributions persists in non-assertoric contexts. "Suppose that you know it will rain today and it might not rain today." "If you know it will rain today and it might not rain today, then you know something that might not happen." Etc. The Gricean story is peculiar to assertions, and therefore insufficiently general.

I think there's a better view in the same spirit. (Well, maybe in the same spirit; I'm not quite sure what the intuitive motivation behind this project is. My suggestion won't vindicate the coherence of concessive knowledge propositions. But like I said, I'm not sure I see why anyone would want to do that.) The line we've been considering is one in which "there is some possibility of p" pragmatically implicates that there is some significant possibility of p. But the existential quantifier is going to have a context-sensitive domain restriction anyway. We could suppose that in the relevant contexts, we're only quantifying only significant possibilities. Then "there is some possibility of p" would, in the relevant context, entail that there is some significant possibility of p.

On this approach, you can still get a lot of the stuff that Fantl and McGrath want. On this view, whether there is a possibility of p will depend on the stakes, since all possibilities are significant possibilities, and whether a possibility is significant depends on stakes. So their 'impurism' would infect 'possibility' talk too. (This is not a result of the view they actually offer, which I'm criticizing: they have 'pure' possibilities, where talk of them implicates results about 'impure' significant possibilities.) But the concessive knowledge attributions will be genuine contradictions.

Tuesday, March 02, 2010

What is fallibilism?

I've long been troubled by failing to understand what 'fallibilism' and 'infallibilism' are supposed to amount to. Here's an example of the sort of discussion I find puzzling.

Bohghossian and Peacocke write:
A priori justification is not infallible justification. Just as one may be justified in believing an ordinary empirical proposition that is empirically revealed on empirical grounds to be false, so one may be justified (non-conclusively) in believing an a priori proposition that is subsequently revealed on a priori grounds to be false.

I find this passage puzzling, for at least two reasons. First, Boghossian and Peacocke characterize a priori propositions for Boghossian and Peacocke as those which can be known a priori; so the idea of an a priori proposition that turns out to be false looks to me to be incoherent.

Second, it's not clear what the second sentence has to do with the first. The second sentence is about what may happen when you're justified in believing something -- that thing may turn out, either empirically or a priori, to be fase. The first sentence, however, isn't a claim about all justification; it's a claim about a priori justification. It can't be that a priori justification is fallible merely because it's possible to be justified in believing some a priori proposition that turns out false; if a priori justification is fallible, then there has to be a sense in which you can be wrong even if you're a priori justified. And that just isn't established or claimed in this passage. Is the idea supposed to be that any time you are justified in believing some a priori proposition, you're justified a priori? That would fill out the enthymeme, but it has the disadvantage to being totally implausible.

So I don't really know what Boghossian and Peacocke are up to here. Or, in general, what people who talk about a priori justification being fallible are up to.

Thursday, February 25, 2010

Knowledge Entails Certainty

The idea that knowledge entails certainty is a very intuitive one. It's easy to forget this, because most of us have it drilled into us, early in our epistemological careers, that embracing a certainty requirement on knowledge leads to skepticism, and we're rightly convinced that skepticsm is crazy, so we start getting used to the idea that there can be uncertain knowledge. Someone can know that p without being certain that p. If we say it enough times, it will stop sounding like a contradiction. And most of us have now said it enough times, so that it has stopped sounding like a contradiction.

Faced with a choice between skepticism and uncertain knowledge, we should indeed choose the latter. But we shouldn't forget that it's an intuitive cost. Given the choice to avoid both, we should consider it seriously.

Is this sounding familiar? It's exactly the opening structure of Lewis's "Elusive Knowledge," but discussing certainty instead of fallibility. I think the argument goes through in just the same way. Contextualists about 'knows' are uniquely positioned to vindicate that knowledge is certain knowledge, and to do it without resulting in skepticism.

The basic structure of it is easy. Let 'knows' and 'is certain that' both be context-sensitive, and let it be that for any context c, the property picked out by the former in c entails that picked out by the latter in c. But a typical effect of asking or enquiring about 'certainty' is to induce a more skeptical context. So I might answer differently to the question "do you know that p" than I would to the question "are you certain that p". But once I've answered 'yes' to the first, I face strong pressure not to say 'no' the second -- or if I do, it will feel like a retraction.

So if you're a contextualist about 'knows,' then you can, if you want, think that knowledge requires certainty. And it looks to me as if there's every reason we should want that. "I'm not certain that p but I know that p" sounds crazy.

Tuesday, February 23, 2010

Contextualist Knowledge Norms

What should a contextualist who likes normative principles involving 'knows' say? Signing up to the knowledge norms means embracing something typically expressed by sentences fitting something like this schema:

(N) Iff S knows p, then S is permitted to phi

Some candidates for phi: S believe p; S rely on p in practical reasoning; S assert p. What I want to do right now is just outline the options for the contextualist who wants to make something suitably in the spirit of (N) true. I see four choices:

(1) Make the normative language contextualist. Now (N) is true in all contexts; "S knows p" is true in all the same contexts in which "S is permitted to phi" is true; the normative language shifts along with the 'knows' language. In skeptical contexts, "S is permitted to phi" will be false, while in nonskeptical ones, it will be true. In his "Knowledge, Context, and the Agent's Point of View," Timothy Williamson assumes this interpretation, and plausibly argues that the resultant view is pretty unattractive. If somebody says "S should phi," and somebody else says "S should not phi," and they're talking about the same S at the same time and using 'phi' to describe the same course of action, then we shouldn't think they're both right. (Jenkins and Nolan have a paper defending contextualist 'ought' discourse, though; I've been meaning to have a close look at it to see if it can help.)

(2) Limit the norm to the claim that (N) be true in any subject's context, leaving the right-hand side with an invariantist interpretation. If "S knows p" is true in S's context, then S is permitted to phi. This is DeRose's view about assertion. (His 2002 paper is not at all clear about how to interpret his version of (N), but his new book is explicit here. See my NDPR review for discussion.) We don't get the oddness that Williamson charges against (1), but there are reasons to be unhappy. For one thing, Jason suggested in seminar that this interpretation is ad hoc. I'm not sure about that. Maybe. Also, as Danielle pointed out in seminar, we do, at least apparently, get some truths that are in tension with what might be the spirit of the knowledge norms. If I'm not in S's context, for example, I might truly say "S knows p but is not permitted to phi." As I mentioned in seminar, DeRose has a defense that mitigates quite a lot against this objection -- in many of the relevant cases, we should expect speakers to adopt contextual standards appropriate to the subject's situation. I think this will work a lot, but not quite enough. (I'm worried about, for example, cases in which speakers are ignorant of the subject's situations. Here is a related blog post.) I'm also worried that there often won't be a determinate standard in place in a subject's context who isn't talking about knowledge (another blog post). I am working on idea about the assertion norm that is in this neighborhood, but, I think, gets around a lot of these objections; more on that soon.

(3) Make (N) true in some particular favored context. Suppose I'm a contextualist and I agree with Williamson when he writes that knowledge is the norm of assertion. One way to do that would be to say that the particular 'knows' relation picked out by Williamson's particular conversational context as he wrote his book is the invariantist norm of assertion. To take this strategy is to embrace a particular disambiguation of (N): Iff S knows(x) p, then S is permitted to phi. Now I'm not sure how plausible this kind of strategy will be in these instances (it certainly runs into at least some of the objections against (2)-type strategies), but it at least represents a position in logical space. I think there are some at least minimally parallel situations where this kind of strategy is correct. (This came out of a discussion I had with Derek Ball and Danielle Sgaravatti over dinner.) Here is an example of a normative principle that contains an uncontroversially context-sensitive term:

(M) S shouldn't murder anybody.

The quantifier "anybody" in English takes a context-sensitive domain, so in theory, we face the same kinds of questions about how to interpret this principle. Strategy (2) here is of course nuts; take some subject S who isn't talking about Derek, such that in his context, 'anybody' does not quantify over Derek. If S were to ask, in his present context, "is anybody taller than 6-foot-2?", the correct answer would be 'no'. According to the (2)-interpretation, (M) carries no prohibition against murdering Derek (who is tall). So the (2)-interpretation of (M) is not the best one. I think the (3)-interpretation of (M) is pretty plausibly correct; an utterance of (M) will typically be one about some privileged domain of individuals. A contextualist could interpret knowledge norms this way if he wanted to. I'm not terribly inclined toward this view, but it looks like a legitimate one.

(4) This is the kind of strategy I'm most interested in at the moment. Like the defender of (1), I want to make (N) true in all contexts, but I don't want to do it by exploiting context-sensitivity of normative language. Instead, I suggest that in at least some instances of the schema, the 'phi' bits will be context-sensitive. (Notice, by the way, that a contextualist needn't adopt a uniform treatment for all instances of the schema. There's nothing stopping him, for example, from employing strategy (4) for the norm of belief by arguing that 'believes' is context-sensitive, picking a favored context for the norm of assertion, and flatly denying the norm of practical reasoning. Norms must be considered one at a time.) Suppose I'm a contextualist about 'believes'. Then I might think that in any context c, it is permissible that 'S believes p' be true in c iff 'S knows p' is true in c. Then we can have 'knows p' and 'is permitted to believe p' swinging together, without the troublesome implication that two people could give contradictory advice, while both being correct. (Two people could each offer sentences that appear contradictory, but the sentences inside their 'oughts' will express compossible propositions.) Maybe you'll think this sounds totally ad hoc. I wouldn't blame you a bit; so far I've just pointed out a bit of conceptual space. But I'm working on a paper that pursues this strategy in some detail, hopefully along with a plausible motivation, with respect to the knowledge norm of belief. Again, more sometime soon.

Thursday, February 18, 2010

Intuition and experience

I know that there is snow outside; this knowledge is based in part on my visual experience. When I look out the window, I have experiences that partially constitute seeing snow. I also know that squares have four sides. Arguably, this knowledge is independent of experience, depending only on my conceptual competence, or rational capacities, or something like that. My knowledge that squares have four sides is not derived from experience, the way that my knowledge that there is snow outside is.

According to certain prominent rationalist views, what explains this difference is that my knowledge about squares, unlike my knowledge of snow, is based not on perception but on intuition. I have the intuition that p, and intuitions are a source of evidence, and so now I have justification for believing that p. It's hard for me to see how, on a view like this, the relevant knowledge comes out independent of experience. For intuitions are experiences, every bit as much as perceptual experiences are. Indeed, some rationalists characterize intuitions phenomenologically: intuitions feel a certain way, and having that sort of feeling provides justification for intuitive beliefs.

On this sort of view, intuitions look to be just another kind of way of experiencing the world. One way that we experience the world is by seeing things; another is by intuiting things. You can call things learned that latter way a priori if you want to, but this just doesn't look to me like belief independent from experience. On the contrary, on this sort of a view, it looks like the a priori beliefs are those that are based on a certain kind of experience: the intuitions.

Tuesday, February 09, 2010

Varieties of Enabling Conditions

A priori justification or knowledge is meant to be independent from experience in some sense. But it's a bit tricky to explain just what that sense is. It's usually allowed that there are some roles for experience that are merely enabling in a way that is consistent with apriority. For example, maybe you think particular perceptual experiences are necessary for possession of color concepts -- you have to have seen yellow in order to entertain thoughts about that color, and so your knowledge that yellow things aren't green requires having had a certain experience. If you think that, you can still think it's a priori that yellow things aren't green, because you think that the role for experience here is not warranting -- it's just part of what lets you entertain the thought in the first place. (Side note: also, if you think that, you should read my colleague Derek Ball's paper to see why you're probably wrong in thinking that you need particular experiences to have these concepts.)

There are other ways for experience to be relevant to the justification of a priori beliefs than by enabling the concepts that are part of their contents. It's also standardly allowed that certain experiences would defeat a priori justification -- the experience of lots of misleading but authoritative testimonial evidence, for example, could make it unreasonable to retain some particular a priori belief. If such obtained, then you wouldn't be justified; therefore, your justification depends on such experience not obtaining. Thus does, for example, Marcus Giaquinto distinguish between 'positive' and 'negative' roles for experience:
We could mark the distinction by saying that if a belief is rationally revisable in the light of future experience, its retention is negatively dependent on experience; and if a belief cannot have been justifiably acquired unless some experience was used as grounds in the process, its acquisition is positively dependent on experience.

But there is room for a kind of dependence on experience that is neither 'negative dependence' nor 'positive dependence' in Giaquinto's sense. And I think that it, too, is consistent with apriority. We can distinguish between the reasons in favor of some belief, on the one hand, and various conditions that are necessary for those reasons to count in favor of the belief, on the other. And in at least some cases, we should think that experiences can play that latter role in a way consistent with apriority. I'll close with an example, and continue with further thoughts and possible applications in another post.

Consider a moderately complicated proof. Suppose it requires a couple dozen lines, and involves fairly lengthy sentences. In fact, it is valid, and indeed, I have produced it correctly -- every step followed from the previous one in a way that I appreciated while writing it down on my blackboard. I've reached my conclusion, but I do not, at this moment, know it to be true. The reason this is so is that the proof is too complicated for me to know it sound straightaway; the chance of making a mistake is too great. Sometimes I apply rules incorrectly; sometimes I accidentally change variables. I don't do this very often -- no more than most philosophers -- but I do it often enough that it would be unreasonable to be confident in the soundness at this point. Instead, I should go back and check my work. I review each step, looking for mistakes, and find that I made none. Now I know the conclusion.

My experience of checking my proof played a significant role in my knowledge of its conclusion. Certainly, that latter knowledge at least counterfactually depends upon it. But these experiences, of course, weren't necessary for the possession of any concepts in the conclusion; I was perfectly capable of entertaining the thought before I began. And this is a positive dependence on experience; it's not just that I need to lack particular misleading experiences. Nevertheless, this looks like a merely enabling role for experience; my belief in the conclusion is not based on my experience of checking the proof; it is based only on the premises. If those are a priori, then my knowledge of the conclusion is too.

So there are ways for experience to play merely enabling roles beyond the ones articulated above.

Wednesday, January 27, 2010

Justification and Action

Fantl and McGrath argue that the combination of the following two views is problematic:
(JJ) If you are justified in believing that p, then p is warranted enough to justify you in phi-ing, for any phi. (Quoted from p. 99)

(Moderate Externalism about Justification) Justification does not supervene on the subject's internal states. In particular, external properties like reliability and Gettierizedness can make a difference in whether one is justified in a particular belief. (Paraphrased from p. 107)

Fantl and McGrath argue that (JJ) implies that 'purist fallibilism' about justification cannot be true. Now as I wrote a little while ago, I don't really buy into the notion of purism. And to be honest, I have some problems with the notion of fallibilism, too -- I'll try to write them up sometime soon. But set all that aside. The basic idea is that, if you accept (JJ), then you think that there might be two subjects that differ only in, for example, how important p is to each subject, such that one is justified in believing that p and the other is not. I guess I think that's right, although I'm thinking of things in a way different from the way Fantl and McGrath do.

Fantl and McGrath think that people who accept this and are also moderate externalists (hereafter 'externalists') "commit themselves to counterintuitive claims about action." First, Fantl and McGrath observe the familiar point that externalists think there could be intrinsic duplicates who differ in their justification facts; externalists, therefore they face the New Evil Demon problem. That's familiar stuff, and, as Fantl and McGrath say, there are many possible responses. But they think things get worse once you also accept (JJ). They write:
Moderate externalists who accept JJ not only have to say that two subjects who differ only in how reliable they are can differ in what they are justified in believing. They also have to say that the subjects can differ in what they are justified in doing. This is counterintuitive. (108)

It's not really clear to me that this is a counterintuitive verdict. But more to the point, I just don't see why Fantl and McGrath think externalists who accept JJ are thereby committed to it. They don't, as far as I can see, explain why they think this result should obtain. It plainly doesn't follow in any direct way from externalism and JJ; externalism says that external properties can influence belief-justification facts, and JJ gives one link between belief-justification and action-justification, but it's just nowhere near strong enough to imply, as Fantl and McGrath seem to think it implies, that external properties can shift action-justification facts.

Take subject LOW who is justified in believing p, and for whom p justifies Xing. Externalists are committed to the possibility, in at least some cases, of another subject, HIGH, intrinsically identical to LOW, who is not justified in believing p. Fantl and McGrath seem to think that externalists are committed by (JJ) to think it possible, consistent with these stipulations, that HIGH is not justified in Xing, but (JJ) just doesn't get them anywhere near that commitment. Indeed, (JJ) is silent about HIGH. This principle tells you about what happens when a subject is justified in believing p; it entails nothing about what happens when a subject is not justified in believing p. For all (JJ) says, p may justify HIGH in Xing, too. (Consider this coherent principle that entails (JJ): If anyone intrinsically identical to you is justified in believing p, then p is warranted enough to justify you in phi-ing, for any phi.)

Suppose we considered a stronger, biconditional, principle:
(JJ*) If and only if you are justified in believing that p, then p is warranted enough to justify you in phi-ing, for any phi.

I don't know whether (JJ*) is plausible or not; it's strictly stronger than the principle Fantl and McGrath defend. It gets around the problem I just raised for their charge against the externalist. But even (JJ*) isn't strong enough to deliver an entailment from externalism to a difference in what actions are justified between LOW and HIGH. Externalism and (JJ*) commit one to the verdict that p cannot justify HIGH in Xing, even though it can justify LOW in Xing. That's a far cry from the stated claim that nothing justifies HIGH in Xing. And I just don't see any plausible argument that this could be the case. It may be, for all (JJ*) says, that HIGH and LOW must be  justified in performing all the same actions, but that they have divergent propositions justifying those same actions. (The plausible way to develop this line, I think, is that HIGH's reasons are a proper subset of LOW's.)

So I don't think that externalists who like (JJ), or even those who accept (JJ*), are committed to the allegedly counterintuitive claims about action that Fantl and McGrath charge.