Monday, October 26, 2009

Sunday, October 25, 2009

Hawthorne against contextualist 'inappropriate'

John Hawthorne gives an argument that contextualists about knowledge face considerable pressure to be contextualists about terms that refer to things widely thought to be linked to knowledge, like 'is epsitemically permitted to assert' or 'relies inappropriately upon in one's practical reasoning'. I'm inclined to agree. He argues, however, that it's not at all plausible to treat words like 'inappropriately' as in the relevant way context-sensitive. Now actually, I'm sort of inclined to agree with that, too, although I'm not at all sure he's right. What I am pretty sure of is that his argument for this conclusion is pretty bad.

Suppose I'm in an everyday context and have pretty good evidence for the true p, such that 'I know that p' is true in my context. Then I go ahead and assert that p and rely on p in my practical reasoning. Now you come along in a more skeptical context where 'Jonathan knows that p' is false. Now you want to say, 'Jonathan ought not to have asserted p' and 'relying on p was inappropriate.' Hawthorne says that a contextualist treatment of this latter is implausible:
Assertability conditions and propriety conditions for practical reasoning just don't seem to vary in that way. The practical reasoning considered above is inappropriate, regardless of what an ascriber is attending to, and parallel remarks apply to the propriety of flat-out assertions of lottery propositions (in the setting envisaged). (90)

I can't read this as anything but a pretty blatant use/mention confusion. The relevant kind of contextualist can explain and predict that “the practical reasoning above is inappropriate, regardless of what an ascriber is attending to” is true. It’s exactly the same reason why, pace Lewis when he’s being sloppy, it’s not a result of contextualism about 'knows' that whether S knows p depends in part on what an ascriber is attending to. That, again, is just the same reason why it’s not true that whether you are female depends on whom I’m talking to. Your gender has nothing to do with me; neither, according to contextualism about ‘knows’, does whether you know p. And neither, according to the hypothetical view under consideration under which ‘inappropriate’ is context-sensitive, does whether your action is inappropriate depend on anything about me.

Saturday, October 24, 2009

Counterfactuals and Knowledge

I'm on the record as thinking there are tight connections between counterfactuals and knowledge.

Robbie Williams, in his "Defending Conditional Excluded Middle," denies this. At least, he argues for a strong disconnect between them. Robbie argues, among other things, that there are strong reasons to accept both (A) and (B):
(A) If I were to flip a fair coin a billion times, it would not land heads a billion times.

(B) If I were to flip a fair coin a billion times, it would not be knowable that it would not land heads a billion times.

Since, Robbie says, (A) and (B) are both true, it can't be that (A) entails the negation of (B) -- therefore Bennett's view, which connects knowledge and counterfactuals in a way implying that entailment, is false. Robbie's argument for (A) is that rejecting it would require rejecting the truth of too many of our ordinary counterfactuals, since they enjoy no stronger metaphysical grounds than those for (A) -- since there's a genuine physical probability of really wacky things happening all the time, we have nothing better than this kind of probabilistic connection between antecedent and consequent in lots of counterfactuals that we want to maintain.

The way Robbie puts the point is that denying (A) would be to commit oneself to an error theory, since it would make our ordinary judgments about ordinary counterfactuals wrong all the time. This move seems to me a bit odd; to my ear, (A) does not look obviously true. Indeed, it looks like we should reject it. That's not to say I can't be moved by an argument in favor of it -- I can -- but if we're in the game of respecting pre-theoretic intuitions, it seems to me that to accept (A) is to embrace something of an error theory, too. We can make it worse if we make the problematic possibility more salient:
(A*) If I were to flip a fair coin a billion times, the possibility of its landing heads a billion times would not be the one to become actual.

If you agree with me that (A*) is equivalent to (A), and that (A*) sounds false, then you must likewise agree with me that Robbie, in embracing (A), commits to a bit of error theory himself. That's not to say it's therefore a bad view; it's just to say that we're already in the game of weighing various intuitive costs. It's not so simple as error theories are bad, therefore (A) must be true.

(Another observation: Robbie thinks it'd be bad to deny (A) because it would make us deny the truth of many ordinary counterfactuals, which play important roles in philosophy. He writes:
Error-theories in general should be avoided where possible, I think; but an error-theory concerning counterfactuals would be especially bad. For counterfactuals are one of the main tools of constructive philosophy: we use them in defining up dispositional properties, epistemic states, causation etc. An error-theory of counterfactuals is no isolated cost: it bleeds throughout philosophy.

Perhaps this is right. But if it is true that counterfactuals play really important roles in construction of philosophical theories, then it's not just their truth that matters -- it's also our knowledge of them. So a view that preserves many of these counterfactuals as true, but that leaves us with very little knowledge about counterfactuals, seems to have a lot of what is problematic in common with the error theory Robbie discusses.)

Robbie gives three arguments for (B). I'll discuss the first two in this blog post; I think that they have analogues against (A).

Friday, October 23, 2009

Epistemic Modals and Contextualism

Here's an insanely simple argument for contextualism about knowledge. I think it's sound, although I'm not sure I'd expect many people to be persuaded by it. I'd be interested in hearing about how readers might think it best to resist it.

Here's premise one. Epistemic modals are intimately connected to knowledge in something like the following way: it might be that p iff the relevant base of knowledge doesn't entail that not-p. This is pretty much standard, I think, although of course people argue about just which knowledge base is the relevant one. This much looks like common ground, for instance, in the debate between contextualists and relativists about epistemic modals. What's at issue there is how the relevant knowledge base gets fixed -- whose knowledge counts. If you need an argument for this connection, just reflect on the absurdity of "it might be that p, but I know that not-p" and "I don't know that p, but it must be that p". (I'm assuming the duality of might and must.)

Here's premise two. In many situations, both of the following obtain: (a) were someone to say "I know that p", that utterance would be accommodated and accepted as true; (b) were someone to say "it might be that not-p", that utterance would be accommodated and accepted as true. For example, in my current situation, I could truly assert "I know that Derek will respond to Paul (because that's what the workshop schedule indicates)". Alternatively, I could truly assert "Derek might not respond to Paul (because it's possible that he'll get sick during the lunch break and have to go home)." (Of course, I can't go both ways; in no context can I say both things; the point is that in some contexts I could say either.)

These two premises, all by themselves, put the invariantist in hot water. Take one of the situations described in premise two, and suppose invariantism is true. In that situation, by premise two, "S knows that p" expresses a truth in some context; therefore, by invariantism, it expresses a truth in all contexts. But, by premise one, "S knows that p" is inconsistent with "it might be that not-p". So this modal claim must be false in all contexts—against the stipulation of premise two.

The obvious solution, from my point of view, is contextualism about 'knows'. Then we can maintain the connection between 'knows' and 'might' in all contexts, and have each sentence true in some context. I don't see any option nearly so appealing for the invariantist. But this argument is so simple that it can't be decisive. So what should the invariantist say?

Sunday, October 04, 2009

Knowledge norm of practical reasoning

In chapter 1 of Knowledge and Lotteries, John Hawthorne introduces the knowledge norm of practical reasoning: "At a rough first pass, one ought only to use that which one knows as a premise in one's deliberations." (p.30) He then immediately qualifies this principle in two ways with this footnote (fn.77):
Qualification 1: "In a situation where I have no clue what is going on, I may take certain things for granted in order to prevent paralysis, especially when I need to act quickly."

Qualification 2: "If I am in a situation where the difference between 'Probably p' and 'p' is irrelevant to the case at hand, I may use 'p' as a basis on which to act even though I only know that probably p."

I don't see why either of these are true in a sense that demands qualification of the rough first pass given above. With regard to qualification 1, let's suppose I'm in a situation where I have no clue what is going on. This isn't literally plausible, of course; in any situation in which my actions are rationally evaluable, I'll have some clue what's going on. So I suppose this must be understood as a kind of exaggeration. Perhaps, for instance, I suddenly find myself being charged at by a rhinoceros, and have no idea how I got there. It's clear, however, that if I just stand pat I will be very shortly gored to death. There's a button nearby with no label; I don't really have any clue what it is or what it does. But it may well be rational to press it, since that's the only real option I have and it's clear that if I do nothing, I will die. Maybe the button will open a trap door for rhino or for me—who knows? It's worth a try.

The thing is, all the premises that I'm using, if I so reason, are things I know. I know that there's a rhino; I know that I'll die if I do nothing; I know that there's a button; I know that maybe if I press the button I'll survive. So I don't see what pressure cases in which I have to act under extreme uncertainty put on the rough principle stated.

Similarly, if I'm in a situation where the difference between 'probably p' and 'p' is irrelevant to the case at hand, why think that I'm using 'p' as a basis to act? We've just stipulated that 'probably p' will do just as well—why not say I'm acting on that known proposition?

I don't really see what Hawthorne is up to in this footnote. (I suspect these issues may be developed in the later paper with Jason Stanley -- I read that a couple of years ago, but need to have another look.)