Hi, my name is Duncan Pritchard. I'm a Professor of Philosophy at the University of Edinburgh, and I'm going to be talking today about a field of philosophy which is known as epistemology. Which is essentially the theory of knowledge. The lecture is going to break into three parts. In part one, I'm going to be talking about the basic constituents of knowledge. In part two, I'm going to be introducing you to a certain problem about offering a theory of knowledge which is called the get here problem. And then part three, I'm going to be introducing you to the problem of radical skepticism. Which is the difficulty of demonstrating that we have as much knowledge as we take ourselves to have. Part one, the basic constituents of knowledge we live in an information age. And that means for most of us, at any rate, information is readily accessible to us at the click of a button. But having lots of access to information isn't much use unless you can filter the good information from the bad information. And that's why knowledge is so important. And that's one reason why philosophers are very interested in trying to determine exactly what knowledge is. And that's what we're going to do in this section. Well, at least, we're going to try and determine the basic constituents of knowledge. Now, the word knowledge gets used in lots of different ways in ordinary language. Here are some examples, David knows that the kettle has boiled. Suilin knows where the secret compartment is. Alasdair knows why the house burned down, Matthew knows how to fly an aeroplane, Michela knows which route to take, Allan knows so-and-so from a TV show and so on. So there's all these different ways in which we use the word knows. Now what we're going to do today is we're going to focus in on a particular way in which we use it. Particularly a fundamental way in which we use the word knows just to narrow down our discussion a little. And this is what's called propositional knowledge which is a knowledge that something is the case. In order to know what propositional knowledge is we need to say a little bit about what a proposition is. The proposition is what is expressed by a declarative sentence. That is a sentence that declares that something is the case. So consider that cat is on the mat that's a sentence that declares the world in a certain way that there is a cat on a mat. But not all sentences are like that. Think of a sentence like, shut that door or yes please. These sentences don't, there not describing the world as being a certain way they don't say that something is the case. So, what we're interested in when we talk about proposition knowledge, knowledge that is knowledge that something is the case. And propositional knowledge, is the kind of thing that can be true or false. So, a sentence like shut that door is not the sort of thing that can be true or false because it doesn't describe the world as being a certain way. But a sentence like, the cat is on the mat, well that could be true, if there is a cat on the mat. Or it could be false, if there isn't a cat on the mat. And if you have propositional knowledge of this proposition, then you know that the cat is on the mat. One way of getting a handle on what propositional knowledge involves is to contrast it to another kind of knowledge called know-how or ability knowledge. Knowing that Paris is the capital of France is a very different thing to knowing how to ride a bicycle. In the last case, the case of knowing how to ride a bicycle, knowledge is connecting with the manifestation of ability or a skill. It's very different from proposition knowledge like knowing that Paris is the capital of France where. Your knowledge is connecting with proposition, you know that that a proposition is the case. There are two basic constituents of propositional knowledge that pretty much everyone agrees upon. The first of these is truth. That if you know a proposition then that proposition must be true. Now natural mount to go the propositions can be true or false. The proposition like the cat is sitting on the mat is true if the cat really is sitting on the mat and false otherwise. So the claim is if you know that the cat is sitting on the mat then that proposition that the cat is sitting on the mat must be true. That is the proposition is describing the world as being a certain way and if you are to know that proposition then. The world must really be the way that that proposition says it is. So to say that propositional knowledge requires truth is to say that you can't know a falsehood. Now, of course, you might think you know a falsehood, and often we do think we do know a falsehood. But we're not really interested in when you think you know something, as epistemologists. But when you actually know it so that's what we mean when we say that knowledge requires truth. The second basic constituent of knowledge that everyone agrees upon, is that if you know a proposition then you must at least believe that proposition. So if you know that Paris is the capital of France then you must at least believe that Paris is the capital of France. Now, of course, sometimes we explicitly contrast belief and knowledge so we might say something like. I don't merely believe the price of the capital of France, I know it. And the suggestion seems to be there that knowledge is different from belief. But of course what we really mean when we say something like that is I don't merely believe it. So I don't just believe but in addition to that I know it. So what we're signalling there is the idea that knowledge is something stronger than belief. Because that's entirely compatible with the thought that knowledge, at the very least, requires belief. Notice that when we say that knowledge requires truth, all we mean by that is that you can't know a falsehood. In particular, we're not suggesting that when you know you must be infallible or you must be absolutely certain. So for example, presumably you know what you had for breakfast this morning. But of course you might be in error about this. It's not as if this is the kind of thing that one could be in error about, that one couldn't make mistakes about. But in so far as you didn't really make a mistake and you really do correctly remember what you had for breakfast this morning. Then by any normal standard for knowledge you account as knowing what you had for breakfast this morning. So knowledge doesn't require certainty. It doesn't require infallibility but it is inconsistent with knowing the full story. The second thing to note here is that when we talk about knowledge of a proposition, we mean just that. In particularly we don't mean knowledge that the proposition is likely or probable, that's a separate thing. So consider the claim that human beings have been to the moon, and compare that with the claim that it's likely or probable that human beings have been to the moon. The second claim is much weaker than the first. The second claim is consistent with the possibility that human beings haven't been to the moon. Now when we say that someone knows that human beings have been to the moon, we mean the first claim, not the second claim. So if we say that without qualification, that's what we mean. We mean that's what they know, not just they know that it's likely or probable, but that they know that this is the case. Now, of course, sometimes it is relevant to hedge the things that we know. That is, to qualify it in some way. So if we're not completely sure about something, we think there's some genuine reason to doubt. Then we might say that what it is we know is just simple that it's likely a probable. So we don't know the proposition simplicity but we know it in this edge to a qualified form. But that it sometimes appropriate to do that doesn't mean it's always appropriate to do that. And in fact in lots of cases, in so far as we apply reasonable standard for what qualifies at knowledge. Then we do know things without the qualification, without the hedge. So for example, I know what I had for breakfast this morning. It's not that I know it's likely or probable that I had such-and-such a breakfast this morning. I actually just know what I had for breakfast this morning. So knowledge requires truth and it requires belief. It requires true belief, that means that knowledge requires getting it right. If you don't get it right, if you don't have a true belief, then you're not even in the market for knowledge. Is there more, though, to knowing than simply getting it right? Well, I think a moment's reflection reveals that there must be. Because there all kinds of ways that one can get it right, I have a true belief, but where one wouldn't count as knowing. So think of this kind of example, imagine a juror in a criminal trial. And let's suppose that they believe the defendant's guilty. But not because they've been listening to the evidence. Let's say they haven't been paying attention to the evidence at all. They form their judgement that the defendant is guilty simply out of prejudice let's say. So they've just formed a snap judgement based on prejudice that the defendant is guilty. Now it could well be that the defendant is guilty, so they've ended up with a true belief. They've got it right but clearly, you wouldn't count as knowing that the defendant is guilty. Simply by forming a snap judgement on the basis of prejudice. Compare this juror, who forms a belief about the guilt of the defendant simply through prejudice. With a different kind of juror who carefully attends to the evidence and thinks through the issues, listens to the testimony from both sides. Listens to the directions of the judge, and so forth, and forms a judgement that the defendant is guilty. So they both, both jurors end up with the same judgement and of course they both get it right. But the first juror who makes the decision simply on the basis of prejudice, this person doesn't know. But the second juror who's sifts through the evidence and carefully weighs it up, it seems they do know. So this raise an interesting question for a epistemologist, knowledge requires more than meritory belief, more than just getting it right. It requires doing the kinds of things that the second juror is doing. Attending to the evidence, thinking things through, coming to a correct judgement. But what is it in general that marks a difference between knowing and really getting it right. And this is what we're going to talk about in the second part of this lecture. There are two basic intuitions that govern our thinking about knowledge. And in particular which govern our thinking about what knowledge requires over and above true belief, over and above merely getting it right. The first is sometimes called The Anti-Luck Intuition. When you know you’re getting it right your true belief in just a matter of luck, so think about the juror who forms their belief through prejudice. Although they've got it right, they've ended up with a true belief, the way in which they've formed their belief is not generally a good way of getting to the truth. And so, insofar as they've got a true belief, it's just a matter of luck that their belief is true. It's just lucky that they've formed a belief through prejudice and it's happened to be true. In contrast, the juror who's carefully sifted through the evidence and thought things through. In so far as they've got a true belief, it seems it's not a matter of luck that their belief is true. Because they've formed their belief in a way which is a good route to the truth. So this is the Anti-Luck Intuition. So when you know your true belief isn't merely a matter of luck. The second fundamental intuition about knowing is sometimes called The Ability Intuition. And this is the idea that when you know, you'll knowing is down to you in some important way and you exercise if your cognitive abilities. That is your abilities which are relevant for formation of true beliefs so take the juror forms their belief through prejudice. Forming beliefs through prejudice, that's not count to ability, that's not a route to truth. In fact, it's actually a root to falsehood. If you want to form false beliefs, that's a very good way to form false beliefs. But if you want to form true beliefs, it's a terrible way of forming true beliefs. In contrast, the juror who carefully attends the evidence and thinks things through. They're using their cognitive abilities. And that's why, some would argue, they count as knowing. Because they've got to the truth through their abilities. Their cognitive success, their true belief, is down to them and their cognitive abilities in some important way. And a way that it isn't when it comes to the juror who forms beliefs through prejudice. So you've got these two fundamental intuitions about knowing. And they may well be closely related actually, they may well up being basically the same intuition. The first is, if you know then your true belief is in the matter of luck. The second is, if you know then your true belief is down to your abilities in some important way. And I say they might end up being the same intuition because you might think well. What is it for your true belief not to be a matter of luck if not for it to be down to your abilities? And what is it for your true belief to be down to your abilities in some significant way but for it to not thereby be a matter of luck? But we've got these fundamental intuitions about knowing they're governing our thinking about what it takes to know over and above Milly getting it right. A prejudice juror doesn't satisfy either of these intuitions and that's at least part of the reason why he doesn't know. Whereas our juror who think it through and attends the evidence, he is satisfying these intuitions. And that's at least part of the reason why we think he does now. So here are the conclusions to part one. We saw that we're going to focus our attentions on a particular kind of knowledge which is called Propositional Knowledge, knowledge that a proposition is the case. Then we saw there are two basic constituents of propositional knowledge that everyone agrees upon. And these are that when you have propositional knowledge the proposition in question must be true and you must believe that proposition. So knowledge requires true belief, it requires getting it right. And then finally we saw that there's actually a lot more to knowing than merely getting it right. One can get it right, have true beliefs in all kinds of ways that aren't appropriate for knowledge. And so this raises the question, what do we need to add to true belief in order to get knowledge?