Different philosophers would answer this sort of question different ways, depending upon how they approach epistemology. On one sort of view, we might think that this is a question about the meaning of the ordinary English verb "to know". And in that case, there seems to be good evidence that English speakers are not always willing to describe someone as "knowing" something just because they believe it and it is true. For example, the Super Bowl is tomorrow. I know nothing about football, but suppose I firmly believe that the Seahawks are going to win. If they do win, would you want to say that I knew they would? A more interesting question, though, to my mind, is simply whether we think there is an important distinction to be made here, whether or not it is one that is made in English. And that, obviously, has to be decided by seeing what work "knowledge", in that sense, can do. It's not at all clear, actually, that all one's true beliefs can "successfully guide...activity in the world" in the same...

I think the answer to this has to be "yes". Suppose I have a sharp pain in my foot. On the basis of that experience, I form the belief that I have stepped on a nail. This belief seems to be justified (and so rational), and it is partly based on evidence available only to me (the felt quality of the pain). The idea that religious belief might be justified on the basis of religious experience has a long history, and some---Swinburne, possibly, but I don't remember for sure---have explicitly drawn the analogy to the role experience plays in the formation of belief.

This doesn't seem at all clear. First of all, the argument assumes that, to know whether we know, on Nozick's account, we would have to know whether a certain counterfactual is true. But this isn't obvious. Water is H2O, but it doesn't follow that, to know whether something is water, you have to know whether it is H2O. Similarly, even if knowledge is (say) Nozick-style tracking, it does not follow that, to know whether you know, you have to know whether you track Nozick-style. That might follow if Nozick's account is construed as providing some kind of conceptual analysis, but even then there are issues that tend to go under the heading "The Paradox of Analysis". Second, even if the foregoing is waived, I don't see why we can't know "whether the subjunctive condition Nozick deems necessary for knowledge is fulfilled". Surely we do have lots of knowledge about possibility, necessity, and counterfactuals. Of course, the epistemology of modal knowledge is a vexed issue, but so is the epistemology of...

I don't myself have a view on whether 2+2=4 is absolutely certain. I suppose it's as certain as anything is or could be. But the question here is different. It's whether that certainty is undermined by doubts about what happens empirically. As Gottlob Frege would quickly have pointed out, however, the mathematical truth that 2+2=4 has nothing particular to do with what happens empirically. It might have been, for example, that whenver you tried to put two things together with two other things, one of them disappeared. (Or perhaps they were like rabbits, and another one appeared!) But mathematics says nothing of this. That 2+2=4 does not tell you what will happen when you put things together. It only tells you that, if there are two of these things and two of those things, and if none of these is one of those, then there are four things that are among these and those. It's hard to see how one's theory of identity could affect that.

This kind of argument has been made by many different philosophers. Two that come immediately to mind are Ludwig Wittgenstein and Donald Davidson. Their considerations are broadly along the lines of: To have any beliefs at all about pigs, beards, etc, I must have some (mostly?) true beliefs about them. For Davidson, the argument involves considerations about what he calls"radical interpretation", the process of making sense of anotherthinker. But that just seems to me to answer the wrong question. The issue isn't about what's involved in making sense of someone. Maybe you do have to agree with the person about a lot of things to do that. The issue concerns what it is to have beliefs. Jerry Fodor has written at length about a great conflict between broadly "pragmatist" theories about the contents of beliefs and, uhh, non-pragmatist theories. According to Fodor's view, for example, being able to have beliefs about pigs involves being in the right kind of causal relation with pigs, and there isn't any...

It's not obvious what the argument is here. Are we trying to argue that we actually are just avatars in a computer simulation? If so, then the argument seems pretty weak. Are we trying to argue that we don't know that we're not avatars in a computer simulation? Then., again, one wants to know what the argument actually is. It seems to be something like: We can't absolutely rule out that we're not avatars, etc, etc. And if so, then, yes, I agree that Putnam's brain-in-a-vat argument is actually pretty hopeless. But my own view, for what it's worth, is that the BIV argument doesn't actually have anything to do with skepticism. (I think it has to do with metaphysical realism, a very different topic.) But the deeper question, I think, is whether knowing that p actually requires being able to rule out the bare possibility that not- p , and not everyone would agree that it does, especially where skeptical scenarios are concerned. Have a peek, for instance, at Jim Pryor's paper "The Skeptic and the...

This is a deep and important question. But let me first correct an apparent misimpression: namely, that, if the central questions of epistemology are semantic questions, then they are unimportant or uninteresting. On the contrary, semantics---the study of meaning---is an important subject in its own right, and it is arguably of central importance in any broadly "conceptual" investigation. So, to the question. This is much disputed nowadays. There are some philosophers who think that many central epistemological questions are, fundamentally, questions about the meaning of the verb "to know". This group includes so-called contextualists, like Keith DeRose, but also philosophers like Jason Stanley and John Hawthorne, whose view is sometimes known as "situation-sensitive invariantism". On these views, our odd reactions to many of the puzzle cases are due to aspects of the way the verb "to know" behaves, or to certain not so obvious features of the concept of knowledge. Contextualists generally hold that...

Sure. I know how the grapes in my back yard taste, but I can't come close to expressing that adequately. I know how John Coltrane plays the soprano sax---with an unmatched genius and intensity---but there's not much else I can really say. And I know how it feels when I see my daughter smile. But if you want me to express that, then I'll have to resort to bad poetry.

You are right that people usually use the word `believe' only if they are not entirely sure. If they were, then they'd say something else, maybe "I know that...", or "I'm sure that...", or just "...", all by itself. But it does not follow that "I believe..." MEANS "I'm not absolutely certain", etc. This point is due to H.P. Grice and is central to his work on `conversational implicature'. We also need to distinguish knowledge from certainty. It may likewise be true that people say "I know" only when they are fairly certain, but it does not follow that "I know..." means: I'm reasonably certain.... What knowledge is, well, that's a disputed question. But let's just pretend it's justified true belief. Then knowing is having a justified true belief, and you could know but not be certain you know, or even be very certain of something you truly believe but not know because you aren't really justified. Most (though not all) philosophers would hold that, if you know that p, then you also believe...

I'm guessing the review to which you refer is Terry Eagleton's in the London Review of Books . I sympathize with Eagleton's frustration, though I don't think he quite plays his cards right. Surely it is true that Dawkins would barbecue any theologian who decided to write a book on evolutionary biology without boning up on the subject, and rightly so. One does rather expect that an author will have some minimal knowledge about what he or she is writing about. But the point (my point, anyway) isn't that Dawkins isn't himself religious. The point is that there are lots of people who study religion, and they do so from many different points of view. Some of these people are my colleagues at Brown, and some of them are Dawkins's colleagues in Oxford. Many of them are religious, but some of them are not. And for Dawkins to write on this topic with, so far as I can tell, essentially no real knowledge of this work is intellectually dishonest, at best. I don't think a knowledge of Duns Scotus and...