This is even further out of sequence, but it’s a response to John Turri’s question at #16.

I think in all of those cases it is clear that there is some true evidence that’s the foundation. What happens in every case is that there is some evidence E (say a news report) which is excellent evidence for false p. Then p obviously entails true q. The speaker believes p on the basis of E, then infers q.

I agree that these are cases of knowledge, and this is bad news for the no false lemmas crowd. But I don’t believe they are cases of false evidence. The evidence is E, not p. If there were a case where there was no true E to start with, then I’d be more impressed, but none of the cases I’ve seen fit that profile.”

In some of the knowlege from falsehood cases, as I recall anyway, the agent doesn’t even believe the nearby truth that would be a good epistemizer if she believed it. So I don’t know why one would be so confident that in the cases the agent’s knowledge is based on the unbelieved truth rather than the believed falsehood.

And as I and others (Klein I believe) have argued. Optimistic declarations about the basing relation in such cases will overascribe knowledge in clear no-knowledge Gettier cases. Hmm, Brian may not classify the Gettier cases in the same way I do…but I’ll leave that aside.

So, for example, the more tickets there are in Clayton’s lottery (and he knows that) the more his evidence supports the proposition that he won’t win. However, the more tickets there are in his lottery, the more unlikely it is that he will in fact win. Now keep the total number of tickets fixed and increase the number of tickets he bought to 1/10 of the total tickets. His evidence supports the assumption that he won’t win somewhat less strongly than it used to when he only had one ticket. Decrease the number of tickets. The support increases. When you get to zero tickets his evidence entails that he won’t win. So, Branden’s discontinuity disappears despite the seeming tension between (1) and (2). Does this make sense?

What I think evidentialists should find really problematic by their own light is that the distinction between the EJ and the well-foundedness of a belief on which this strategy relies seems to undermine the internalist credentials of the theory. Isn’t it?

Also, throughout this thread, you seem to suggest that there can/might be no evidence for or against the correctness of a certain logical system (or at least that you doubt there can be any such evidence). Is that right? If so, when and if you have a chance, I’d be interested to hear more about why you think so. Your Crispin, Graham, and Ringo seem to have different beliefs about what the correct logical system is and, presumably, each has his reasons for believing what he believes (or at least their well-known real world counterpart do). And, also presumably, these reasons can be good or bad reasons, right? But then why think that they cannot have evidence for or against the correctness of a certain logical system? Is it because you think that evidence is always empirical evidence and that there can’t be empirical evidence for or against the correctness of a logical system?

And, thanks Clayton for the very helpful and informative reply. That’s just the sort of thing I was yearning for! I’ll have to think a lot more about all of this — but this thread has been quite useful for me, so thanks all!

(a) When you have false beliefs about what can be inferred from what; and
(b) You make inferences that accord with the true theory of inference, but not with your beliefs, then

you end up with justified true beliefs that are not knowledge.

This doesn’t seem like a particularly happy result to me, but it’s certainly consistent if one wants to hold on to evidentialism about justification.

‘I still don’t see why you think an evidentialist would have to affirm (or deny) that S’s claim to know that p can be defeated by some other unjustified belief of S’.

After all evidentialism is primarily an account of epistemic justification not knowledge and an evidentialist would seem to be able to accept that something can defeat a justified true belief’s claim to constitute knowledge.

‘I still don’t see why you think an evidentialist would have to claim that S’s claim to know that p can be defeated by some other unjustified belief of S’

I’ve been thinking about Branden’s challenge and the evidence is piling up fast that there’s not much interesting I can say in response.

A couple of points. Branden knows that I think there cannot be false, justified beliefs. (So does John, and it’s a testament to his character that we’re still philosophy pals and he doesn’t shun me in public given what he knows.) I wouldn’t want to argue from the fact that that there cannot be false, justified beliefs to the denial of Branden’s (1):

(1) Some evidence can very strongly (in fact, arbitrarily strongly, so long as there isn’t a logical entailment) support some false claims.

An example of (1). I know I’m a philosopher with a philosopher’s bank account and I know that I have a ticket for tomorrow’s lottery. I have evidence that provides exceptionally strong support for the proposition that I won’t be rich by Monday as my only chance for getting rich is winning the lottery. As the lottery gets bigger and bigger, the degree to which my evidence supports the hypothesis that I’ll still be poor on Monday will increase accordingly.

Someone who says that there cannot be false, justified beliefs should say that the permission to believe p depends upon whether p (obviously) but doesn’t depend upon whether the believer has evidence that entails that the subject has a permission to believe p. (They should be fallibilist and anti-evidentialist.) In other words, they should say that the deontic properties of a belief does not supervene upon the believer’s evidence. [Suppose someone says, as Sutton does, that justified beliefs just are items of knowledge. It follows that there would be no false, justified beliefs. It does not follow, however, that if you justifiably believe p and you have evidence E that anyone who has evidence E and believes p justifiably believes p because it’s possible for someone to have E and not know p because someone could have E and yet ~p. Now, someone could object and say that since E=K this kind of case isn’t possible. But, I don’t accept E=K. Gettier cases and cases of inferential knowledge seem like counterexamples to E=K. Also, I don’t accept JB = K because of Gettier cases. So, if we retain the factivity of justified belief and weaken the requirements for justified belief, we can introduce a new range of externalist accounts of justified belief on which two subjects can have precisely the same evidence but only one subject has the permission to believe some proposition. (For the record, I think S’s belief is justified iff p and the subject reasonably take it to be the case that p or is personally justified in believing p.)]

I take it that Branden’s challenge is so vexing because you can tell a (convoluted?) story about how (1) could be true even if evidence is factive (which is a separate issue from the factivity of justified belief) but then your views seem to be in tension because you accept (1) but have to reject:

(2) No evidence can entail any false claims.

Maybe the weirdness is this:

If evidence is factive, it seems that the degree to which some arbitrary proposition can be supported by some body of evidence is going to be a function of the way the world happens to be in terms of its contingent features rather than by relations between the proposition and the evidence

That can’t really be the weirdness, however, because if evidence is factive, I think you can’t have cases where there are two words, w1 and w2, where some subject in w1 has evidence E and P(p/E) = 1 and some subject in w2 has evidence E and P(p/E) < 1.

Maybe the oddity is supposed to be this instead:

If evidence is factive, it will be an empirical matter rather than an apriori matter whether some arbitrary proposition can be supported by entailing evidence or not.

That can’t be the oddity, however, because someone who defends the factivity of evidence can place epistemic restrictions on what it would take to get something into your evidence such that you could know from the armchair whether some arbitrary proposition could be supported by entailing evidence or not. For example, if p could only be part of your evidence if p is knowable from the armchair or apriori, you could know whether some arbitrary proposition could be supported by entailing evidence or not without having empirical knowledge of the way things happen to be.

That’s a tad disingenuous, you might say, because I think that (i) p can be part of your evidence only if p, (ii) whenever you know p non-inferentially p is part of your evidence, and (iii) the scope of non-inferential knowledge includes more than just that which we can know from the armchair. I think this means that if you accept the factivity of evidence and don’t limit evidence to that which can be known apriori or from the armchair you’ll have to just bite this bullet:

If evidence is factive, you cannot know from the armchair or know apriori whether some arbitrary proposition could receive support from entailing evidence or not until you know what your evidence is our could be (in your world, depending upon what you come to know later) and that kind of knowledge will be empirical knowledge.

This might be a bullet that you shouldn’t look forward to biting, but you could say that it’s not the worst thing in the world. In conceding this, you can still say that it isn’t a contingent matter whether some p could receive support from entailing evidence or not from some particular body of evidence and it is still an apriori matter whether some particular body of evidence could provide entailing support for the propositions it provides that support for.

I think that’s the best that someone can do if they think that evidence is factive. Try to limit the extent to which empirical knowledge infects knowledge concerning evidential relationships and show that you can accommodate some of the intuitions that might (this is a guess) lead someone to think that accepting (1) and rejecting (2) creates a tension we shouldn’t.

Thanks for answering my question. Now I see more clearly what you meant, but I still don’t see why you think an evidentialist would have to deny that S’s claim to know that p can be defeated by some other unjustified belief of S, q, insofar as S’s belief that p fits S’s total evidence (and q doesn’t). (And, in any case, Earl and Rich, for example, distinguish between epistemic justification and well-foundedness and, I think, they would claim that the belief that p is justified though not well-founded).

Moreover, I suspect there is still a tension between your story and evidentialism. You say ‘I didn’t mean to suggest that [classical logic is] the kind of thing susceptible to being supported by evidence’, but you also say ‘Assume that S believes that H cannot be properly inferred from E’. I have trouble seeing how there can be beliefs that are not susceptible to being supported by evidence (at least on an evidentialist framework). The evidence for some beliefs may be a priori evidence (such as “intuitings” or “seemings”) but insofar as you can have a belief about something it also has to be the case that belief either fits your total evidence or it does not, for there are no beliefs that are neither justified nor unjustified.

I think in all of those cases it is clear that there is some true evidence that’s the foundation. What happens in every case is that there is some evidence E (say a news report) which is excellent evidence for false p. Then p obviously entails true q. The speaker believes p on the basis of E, then infers q.

I agree that these are cases of knowledge, and this is bad news for the no false lemmas crowd. But I don’t believe they are cases of false evidence. The evidence is E, not p. If there were a case where there was no true E to start with, then I’d be more impressed, but none of the cases I’ve seen fit that profile.