Wednesday, February 06, 2008
Does Knowing Figure Ineliminably in Causal Explanations?
In chapter 2 of Knowledge and its Limits, Williamson argues that in some cases 'reference to states of knowing is essential to the power of a causal explanation' (63). He notes that in order to prove that this held for a given causal explanation 'one would need to show that [the reference to states of knowledge] could not be eliminated in favour of any combination of believing, truth, and so on' (63). So instead of providing such a proof, he offers a general recipe for countering such suggestions:
'Given a potential substitute for 'knows', suppose that it does not provide a necessary and sufficient condition for knowing. One then constructs possible cases in which the failure of necessity or sufficiency makes a causal difference, making the proposed substitute not even causally equivalent to knowing. The potential substitute avoids this problem only if it does provide a necessary and sufficient condition for knowing.' (63)
So suppose one substitutes 'believes truly' for 'knows' in some causal explanation. To take Williamson's example, we can ask why a burglar spent the entire night ransacking a house, given that he increased his risk of being caught the longer he stayed. Start with the explanation that he knew that there was a diamond in the house. If we merely say he truly believed that there was a diamond in the house, we give a worse explanation of why he stayed so long, risking detection. For suppose he truly believed that there was a diamond in the house because he had been told that there was a diamond under the bed, when in fact the only diamond was in a drawer in the study. In that case, it seems he would be likely to give up his search after looking underneath the bed, having given up his true belief that there's a diamond in the house. Williamson now argues:
'Given suitable background conditions, the probability of his ransacking the house all night, conditional on his having entered it believing truly but not knowing that there was a diamond in it, will be lower than the probability of his ransacking it all night, conditional on his having entered it knowing that there was a diamond in it. In this case, the substitution of 'believe truly' for 'know' weakens the explanation, by lowering the probability of the explanandum conditional on the explanans.' (62)
If we try to get around this point by substituting 'believes truly without reliance on false lemmas', we can construct a scenario where the burglar's true belief does not rely on false lemmas, but he receives misleading evidence in the course of his search, which makes it less probable that he would risk staying the entire night than if he knew that there was a diamond there (63). We could switch to 'believes truly without reliance on false lemmas and with stubbornness in one's belief in the face of counterevidence', but then, since such stubbornness is not necessary for knowledge, we can find an alternative cases in which the failure of necessity for knowledge makes a causal difference. And so on; for each proposed substitute for 'knows', there will be an argument that that substitute doesn't cut it.
Frank Jackson has a paper offering a response to this argument (which I think is appearing in Duncan Pritchard and Patrick Greenough's Williamson on Knowledge volume with OUP), but I have a different worry. I'm just not sure with what right Williamson can assume that for any substitute which does not provide necessary and sufficient conditions for knowledge, there will be a possible case in which 'the failure of necessity or sufficiency makes a causal difference, making the proposed substitute not even causally equivalent to knowing'. That seems to beg the question against someone who wants to maintain that reference to states of knowing are not essential in a given causal explanation; it's just an assertion that any non-equivalent substitute can't be causally equivalent.
So far I've been arguing that a crucial premise in Williamson's argument for the essentiality of reference to states of knowing in some causal explanations is question-begging; it's just an unwarranted assumption that any substitute for 'knows' which does not give necessary and sufficient conditions for knowing cannot be causally equivalent, and I don't see why Williamson's opponent should grant that. Without that premise in place, I don't see how consideration of a few cases suffices to get us to Williamson's conclusion. But clearly my point here would be much stronger if one could show that premise to be not just under-motivated, but actually mistaken. I think Williamson's own account of knowledge provides materials for one attempt to show this.
Williamson holds that knowledge requires safe belief; that is, the following subjective conditional must hold:
Safety: Bp -> p
(In words: in the closest worlds in which you believe that p, p is true: your belief could not easily be false)
Now suppose our burglar enters the house with a confident, true belief that's not based on any false lemma that there's a diamond in the house, but that belief is unsafe. Now, how do we continue the case so that the failure of his belief to be safe makes it more likely that he'd leave the house before morning than if he knew? The relevant difference between him and his counterpart who knows is just that the modal space around them is different. I don't see how to continue the case so that this modal fact makes the kind of causal difference Williamson needs it to.
I don't mean to suggest that Williamson holds that knowledge is just confident, safe, true belief. Of course he'd reject this analysis of knowledge, just as he'd reject any other. Williamson writes, 'the search for a substitute for knowing in causally explanatory contexts is forced to recapitulate the history of attempts to analyse knowing in terms of believing, truth, and so on, a history which shows no sign of ending in success' (63). Though I'm not as pessimistic as Williamson on this score, I take the point. It is going to be very hard to specify the right substitute for 'knows', without just describing it as 'knowledge minus safety'.
But the general point I've tried to make should be clear despite these - admittedly difficult - complications; once we add modal constraints such as safety onto knowledge, it becomes hard to see how on what grounds we should hold that any substitute which does not give sufficient conditions for knowledge must fail to be causally equivalent. And that's a crucial premise in Williamson's argument that reference to states of knowing are essential in some causal explanations.
'Given a potential substitute for 'knows', suppose that it does not provide a necessary and sufficient condition for knowing. One then constructs possible cases in which the failure of necessity or sufficiency makes a causal difference, making the proposed substitute not even causally equivalent to knowing. The potential substitute avoids this problem only if it does provide a necessary and sufficient condition for knowing.' (63)
So suppose one substitutes 'believes truly' for 'knows' in some causal explanation. To take Williamson's example, we can ask why a burglar spent the entire night ransacking a house, given that he increased his risk of being caught the longer he stayed. Start with the explanation that he knew that there was a diamond in the house. If we merely say he truly believed that there was a diamond in the house, we give a worse explanation of why he stayed so long, risking detection. For suppose he truly believed that there was a diamond in the house because he had been told that there was a diamond under the bed, when in fact the only diamond was in a drawer in the study. In that case, it seems he would be likely to give up his search after looking underneath the bed, having given up his true belief that there's a diamond in the house. Williamson now argues:
'Given suitable background conditions, the probability of his ransacking the house all night, conditional on his having entered it believing truly but not knowing that there was a diamond in it, will be lower than the probability of his ransacking it all night, conditional on his having entered it knowing that there was a diamond in it. In this case, the substitution of 'believe truly' for 'know' weakens the explanation, by lowering the probability of the explanandum conditional on the explanans.' (62)
If we try to get around this point by substituting 'believes truly without reliance on false lemmas', we can construct a scenario where the burglar's true belief does not rely on false lemmas, but he receives misleading evidence in the course of his search, which makes it less probable that he would risk staying the entire night than if he knew that there was a diamond there (63). We could switch to 'believes truly without reliance on false lemmas and with stubbornness in one's belief in the face of counterevidence', but then, since such stubbornness is not necessary for knowledge, we can find an alternative cases in which the failure of necessity for knowledge makes a causal difference. And so on; for each proposed substitute for 'knows', there will be an argument that that substitute doesn't cut it.
Frank Jackson has a paper offering a response to this argument (which I think is appearing in Duncan Pritchard and Patrick Greenough's Williamson on Knowledge volume with OUP), but I have a different worry. I'm just not sure with what right Williamson can assume that for any substitute which does not provide necessary and sufficient conditions for knowledge, there will be a possible case in which 'the failure of necessity or sufficiency makes a causal difference, making the proposed substitute not even causally equivalent to knowing'. That seems to beg the question against someone who wants to maintain that reference to states of knowing are not essential in a given causal explanation; it's just an assertion that any non-equivalent substitute can't be causally equivalent.
So far I've been arguing that a crucial premise in Williamson's argument for the essentiality of reference to states of knowing in some causal explanations is question-begging; it's just an unwarranted assumption that any substitute for 'knows' which does not give necessary and sufficient conditions for knowing cannot be causally equivalent, and I don't see why Williamson's opponent should grant that. Without that premise in place, I don't see how consideration of a few cases suffices to get us to Williamson's conclusion. But clearly my point here would be much stronger if one could show that premise to be not just under-motivated, but actually mistaken. I think Williamson's own account of knowledge provides materials for one attempt to show this.
Williamson holds that knowledge requires safe belief; that is, the following subjective conditional must hold:
Safety: Bp -> p
(In words: in the closest worlds in which you believe that p, p is true: your belief could not easily be false)
Now suppose our burglar enters the house with a confident, true belief that's not based on any false lemma that there's a diamond in the house, but that belief is unsafe. Now, how do we continue the case so that the failure of his belief to be safe makes it more likely that he'd leave the house before morning than if he knew? The relevant difference between him and his counterpart who knows is just that the modal space around them is different. I don't see how to continue the case so that this modal fact makes the kind of causal difference Williamson needs it to.
I don't mean to suggest that Williamson holds that knowledge is just confident, safe, true belief. Of course he'd reject this analysis of knowledge, just as he'd reject any other. Williamson writes, 'the search for a substitute for knowing in causally explanatory contexts is forced to recapitulate the history of attempts to analyse knowing in terms of believing, truth, and so on, a history which shows no sign of ending in success' (63). Though I'm not as pessimistic as Williamson on this score, I take the point. It is going to be very hard to specify the right substitute for 'knows', without just describing it as 'knowledge minus safety'.
But the general point I've tried to make should be clear despite these - admittedly difficult - complications; once we add modal constraints such as safety onto knowledge, it becomes hard to see how on what grounds we should hold that any substitute which does not give sufficient conditions for knowledge must fail to be causally equivalent. And that's a crucial premise in Williamson's argument that reference to states of knowing are essential in some causal explanations.
Labels: Epistemology, Tim Williamson
# posted by Aidan @ 7:07 PM 
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I think you're right that there's not really enough to go on in Williamson's discussion of this issue--he's just throwing out some cases and counting on us to get the sense that a similar treatment is possible in all unexamined cases. That's not the strongest form of argument there is.
My reaction to your safety case, however, is that it's underdescribed. Two cases can't merely differ in that one is safe and the other isn't. Something else about the cases has to be different. Rather, the failure of safety might be because of a false-lemma, a lack of a causal connection, an unwillingness to consider defeating evidence, etc. It's possible to subsume a whole heck of a lot of Gettier examples under the rubric of not-safe. But for most ways in which a belief can be unsafe, it's plausible to think that a causal difference could be constructed.
So relative to the argumentative standards going on here, I think Williamson has some ground to say "well, you can't just call the belief unsafe. Tell me how it's unsafe."
My reaction to your safety case, however, is that it's underdescribed. Two cases can't merely differ in that one is safe and the other isn't. Something else about the cases has to be different. Rather, the failure of safety might be because of a false-lemma, a lack of a causal connection, an unwillingness to consider defeating evidence, etc. It's possible to subsume a whole heck of a lot of Gettier examples under the rubric of not-safe. But for most ways in which a belief can be unsafe, it's plausible to think that a causal difference could be constructed.
So relative to the argumentative standards going on here, I think Williamson has some ground to say "well, you can't just call the belief unsafe. Tell me how it's unsafe."
Thanks for the comment. I'm not sure I'm getting the point though, so let me see if I can pin it down.
Is the claim that if a belief fails to satisfy safety, it's because the subject is either in a Gettier case, a barn case, in possession of a defeater, or not standing in the right kind of causal connection, etc etc? In full generality, I'm not sure this holds. We can construct cases in which it was overwhelmingly likely that the subject would find himself in an epistemically bad case, but as luck would have it, did not. Here's a case from Neta and Rohrbaugh:
'I am drinking a glass of water which I have just poured from the bottle. Standing next to me is a happy person who has just won the lottery. Had this person lost the lottery, she would have maliciously polluted my water with a tasteless, odorless, colorless toxin. But since she won the lottery, she does no such thing. Nonetheless, she *almost* lost the lottery. Now I drink the pure, unadulterated water and judge, truly and knowingly, that I am drinking pure, unadulterated water. But the toxin would have not flavored the water, and so had the toxin gone in, I would still have believed falsely that I was drinking pure, unadulterated water. The actual case and the envisaged possible case are extremely similar in all past and present phenomenological and physical respects, as well as nomologically indistinguishable. (Furthermore, we can stipulate that, in each case, I am killed by a sniper a few moments after drinking the water and so the cases do not differ in future respects).'
(Neta and Rohrbaugh 2004: 399-400. These guys are using such cases to argue against a safety requirement on knowledge)
Neta and Rohrbaugh contrast this case with barn cases on the grounds that my actual circumstances in the case described are epistemically favorable - it's just that things are messed up in most of the closest worlds around me - while in barn cases my actual circumstances are epistemically unfavorable (401).
So, returning to our persistent burglar, make it improbable that he ends up in epistemically favorable circumstances wrt his belief that there's a diamond in the house, but have him luck out. These are the kinds of cases I had in mind when I suggested that the burglar could fail to have a safe belief, yet otherwise be in an epistemically favorable position.
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Is the claim that if a belief fails to satisfy safety, it's because the subject is either in a Gettier case, a barn case, in possession of a defeater, or not standing in the right kind of causal connection, etc etc? In full generality, I'm not sure this holds. We can construct cases in which it was overwhelmingly likely that the subject would find himself in an epistemically bad case, but as luck would have it, did not. Here's a case from Neta and Rohrbaugh:
'I am drinking a glass of water which I have just poured from the bottle. Standing next to me is a happy person who has just won the lottery. Had this person lost the lottery, she would have maliciously polluted my water with a tasteless, odorless, colorless toxin. But since she won the lottery, she does no such thing. Nonetheless, she *almost* lost the lottery. Now I drink the pure, unadulterated water and judge, truly and knowingly, that I am drinking pure, unadulterated water. But the toxin would have not flavored the water, and so had the toxin gone in, I would still have believed falsely that I was drinking pure, unadulterated water. The actual case and the envisaged possible case are extremely similar in all past and present phenomenological and physical respects, as well as nomologically indistinguishable. (Furthermore, we can stipulate that, in each case, I am killed by a sniper a few moments after drinking the water and so the cases do not differ in future respects).'
(Neta and Rohrbaugh 2004: 399-400. These guys are using such cases to argue against a safety requirement on knowledge)
Neta and Rohrbaugh contrast this case with barn cases on the grounds that my actual circumstances in the case described are epistemically favorable - it's just that things are messed up in most of the closest worlds around me - while in barn cases my actual circumstances are epistemically unfavorable (401).
So, returning to our persistent burglar, make it improbable that he ends up in epistemically favorable circumstances wrt his belief that there's a diamond in the house, but have him luck out. These are the kinds of cases I had in mind when I suggested that the burglar could fail to have a safe belief, yet otherwise be in an epistemically favorable position.
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