 In this chapter, Russell starts exclusively stating whether philosophy and specifically foundation of metaphysical beliefs can be knowledge. And so if you recall what he did in the last chapter, the question really kind of breaking it down is, is it going to be a true belief that's either derived or justified with intuition and this highest guarantee of truth? And he answers it very quickly and says, well, no. And then he spends the rest of the chapter providing an example from Hegel. Okay. But then he finishes doing something else. He asks the question, well, I mean, at least answer the question, well, then what can philosophy do in terms of knowledge? And his answer is that philosophy is a really fantastic way for providing criticism. Russell talks about Hegel. Now the description that Russell gives for Hegel, he tries to do what, two or three pages, what Hegel did in hundreds. And as he said in the text, there's lots of debate about what Hegel has to say. Okay. So I'm not going to try to reproduce Hegel or Hegel here, I'm not going to try to reproduce everything of what Russell has to say about that argument. But what I would like to do is I'm going to try to illustrate the same point that Russell has by using a much more simplified case. So let's consider these four statements about objects, right? These are very commonplace statements. So the first one is that at least some objects have parts, right? So think about your car. And it's got spark plugs, tires, windshields, a steering column, lots and lots of parts on a car. Or even yourself. Right? We say that we are our bodies. We have hearts, lungs, kidneys, spleen, skin, bones, eyeballs, hair, everything, you know, all of that. We have these parts. Now so when we say that they have parts, we're not, what we're saying is that, well, there's a distinction between these things. There's a difference between my eyeballs and my heart. Okay. The second claim about objects is that at least sometimes, or even majority of times, objects can survive the loss of parts, even the loss of replacement of parts. So your car, you might have changed the spark plugs or got new tires or had the entry hold or something like this. We think, well, I didn't have to go down and file with the DMV with a whole new car. No, you didn't have to do that. And you didn't take your car around to your neighbor and say, hey, look at my brand new car. Didn't you just replace the tires? Well, yeah, but it's a brand new car. No, you don't think that. You think that you still have the same car, you just have a different part. Or even with yourself, right? You lose parts in your replacement, your skin. You lose hundreds of skin cells every day and your replacement in your skin. As a matter of fact, your body is going through a continual process of loss of replacement. So we got that objects have, at least some objects have parts. Objects survive the loss of replacement of parts. The third claim is that more than one object cannot occupy the same place at the same time. So I'm standing here, but there's no chair here at the same place at the same time, right? I can't walk into and occupy the same space as the camera. I can't occupy the same space as the floor or anything like that. Now we think that objects occupy most one place at a time. And then finally, we say that objects, you know, when you're like looking at me and you say, well, what's there? It's like, well, that's the body. What's the body? What's the collection of organs? So at least sometimes, or maybe all the time, right? We think that objects just are the collection of parts. There's nothing more to it than that. So if I sit here and I say, well, here I am. And I say, well, what parts do I have? It's like I got my heart, my brain, my kidney, my lungs, my fling, my skin, my bones, my eyeballs. I've got all that. And then somebody asks, well, where's your body? I just told you, right? It's all the parts. Imagine going out your car. And somebody said, hey, where's your car? And he said, well, it's right here. And the person said, well, I see the tires and the windshield, the doors, the engine, I see the tailpipe, the tail lights. I see all of that. But I don't see the car. Something is wrong there, we would say. If you have all the parts, you have just the thing. There's nothing more on top of it. OK. Well, each of these is really intuitive, right? We want to keep each of these beliefs. But we have an interesting problem when we consider whether all these beliefs can be true together. So we're asking the question of whether all of these intuitions, these intuitive beliefs about objects can be true together. Well, consider this cat, Tybalz. Tybalz is an unfortunate, you know, it's a cat, right? Doing normal cat things has cat legs, cat head, cat tail, cat body, right? It's a cat, right? But Tybalz has an unfortunate accident. Tybalz loses his tail. Say it had a fortunate accident with a car door or something, I don't know. So Tybalz's tail gets separated from Tybalz. Now, for ease of reference, let's call the tailtib. Let's call the tailtib. So we're going to name the tail. OK. Well, so now here's the question. Did Tybalz survive the loss of his tail, the loss of Tybalz? Well, I mean, we think so, right? We don't think, oh, my gosh, you killed my cat, right? I mean, you're probably saying, oh, my gosh, you hurt my cat. My cat's tail is now gone. But we don't think that the cat has now died. We think that Tybalz has survived. Well, if you think that, then you're denying that last intuition about Tybalz, about objects, because Tybalz was a part of Tybalz. The cat had parts, legs, tail, head, body. The body had heart, lungs, fur, skin, everything else like that. So Tybalz lost Tybalz, but Tybalz survived. But if objects just are their parts, then Tybalz did not survive. Something else did survive. Something else, or something else survived, something else began to exist in the place of Tybalz. Now that's, now we don't think that that's true. But so if we say that Tybalz survived, then we're committed to the claim that, you know, they were committed to the rejection of that fourth claim, that there's something else to Tybalz than nearly the collection of all the parts. Well, suppose you take another way. Suppose you say, well, of course Tybalz survived, because Tybalz is not his tail. Now you don't want to quite reject four. You just want to say, well, Tybalz is not his tail. Well, then what is Tybalz? Because it sure seemed like the tail was a part of Tybalz. Do you start taking away parts? OK, well, what are you doing, right? You take away the legs, and you say, well, no, Tybalz can survive without legs. You take away the ears, and you say, well, Tybalz can survive without ears. It's getting kind of gruesome at this point. Sorry, I think it's traumatizing anybody. But the question remains, well, where is Tybalz? What is Tybalz? Well, if you keep removing parts, trying to figure out where Tybalz is, it sure seems like you're either going to do one or two things. You're either going to say that there's an essential part of Tybalz that makes Tybalz what he is, and the legs and the tail and the ears. That's just kind of added on. Well, if you're doing something like that, you're probably rejecting the first claim. If you're saying that, well, Tybalz is really here, but the rest of it is just kind of extra stuff, you're seeing what Tybalz really is has no parts. It's probably not the direction you want to go. Because then you're saying, well, what happens is you have objects out there with just a whole bunch of other things added on. So no object actually has parts. There's just the thing that is the object and then some added materials. Well, let's try a different approach. Suppose we say, well, no, Tybalz did survive, and we're just going to go and reject four. We'll say, well, there's something more to Tybalz than merely the collection of Tybalz parts. So we got this Tybalz plus tip. Now, we would also talk about the legs and the ears and everything else. So we have all these parts together. Now, all these parts together don't make Tybalz. If we're trying to reject four, if we reject four, we say all these things together don't make Tybalz. But if they don't make Tybalz, look what happens. You have Tybalz occupying this space, but you also have the collection of all the Tybalz parts. So now what you have is Tybalz and a collection of Tybalz parts. I mean, collections are things, right? We talk about pounds of coffee. We talk about piles of sand. We talk about, yeah, I just said the collection of Tybalz parts. You can understand what I'm talking about. But if we have both Tybalz and the collection of Tybalz parts, then we have two things occupying the same space at the same time. So if we reject four, if we reject the idea that things just are their parts, then we have this problem of also rejecting three, that we now we have more than one thing existing at a place at a time. Well, suppose you want to avoid this mess altogether. You throw your hands up in your entire idea, and say, well, oh, fine, Tybalz just didn't survive. There's something else there. Whatever it is. And all this time Tybalz really just didn't survive. Well, as I said at the beginning, you're made of parts and you've lost and replaced parts. And if you go with that, then you're saying that you do not survive a very long amount of time. I mean, as soon as you do this, you brush off skin cells. That happens right there. You brush off skin cells. You no longer survive. Now that's a conclusion you probably don't want to accept. So trying to figure out, well, what's happening with Tybalz or even any of us when we lose just a little piece of us and something else replaces it is not an easy thing. Because these four statements, we want to keep all four of these statements. But they can't all be chewed together. Rejecting any one of them comes with a very heavy price. So this is the problem that's posed by intuitions. We had these intuitions. We had these beliefs. But they can't all be chewed together. And even some proposed solutions to the Tybalz case that I just described, there are some solutions that try to account for all four. But usually, almost not usually, almost always they butt up against some other kind of intuition that wasn't listed earlier. So what happens is that these metaphysical theories wind up rejecting at least one of these intuitions. Now, logic dictates that we can't keep all of the intuitions. Each of them is plausible, but together they generate contradictions. But if we can't keep all the intuitions, logic tells us that we can't keep all of the intuitions. But logic doesn't tell us which combination of intuitions we must keep. We can't keep all of them, but it doesn't tell us which subset of the intuitions we should keep. And with these different metaphysical theories, they wind up keeping some, but not all. So logic doesn't tell us which one to accept. And so this is that Russell's saying that logic is freeing because you can see with these possibilities that are beyond just what's given by our empirical knowledge. Empirical knowledge, when we talk about having empirical content, but as Russell has quick to point out, empirical content is always, always, always combined with some kind of a priori knowledge in order to generate beliefs. The principle of difference in the principle of induction are just two of them, the two big ones. And logic doesn't tell us which subset of these intuitions to keep. But depending on your subset, you're going to have different beliefs about what your empirical content is giving you. And we've already seen Descartes compared to Barclay compared to Hume compared to Kant. So logic doesn't tell us which subset to keep. Logic, and Russell says, what logic does is it frees us to look at a variety of different approaches. Now since logic doesn't tell us which subset to keep, there's nothing that tells us which theory is true. So since there's no theory that just comes out on top of all of these different priori theories, we do not have certainty. And since we don't have certainty, we don't have knowledge. You have probable opinion. OK, you have probable opinion. Some of us have error. That's going to happen. But most what you get from philosophy is not knowledge, but it's probable opinion. And Russell, frankly, is just not too confident as to how probable that opinion is to begin with. He probably thinks it's closer to true belief than anything, if it's true at all. Now that doesn't mean, so that answers at least the explicit question that Russell gives us in the beginning. Can we have philosophical knowledge? But it doesn't mean philosophy is without its uses. So what philosophy is really great for, Russell says, is criticism. Criticism. What does it mean by that? It doesn't mean that we just sit here and say, oh, I'll use theories. You're just that. It doesn't mean that. What philosophy can provide us with is a way of saying, OK, here you have a particular kind of reasoning used in your field, say, the physical sciences. Philosophy's task is to question, OK, how is that justified? If it's justified, how is it justified? And then to look at the reasons for that justification, to look at the argument as a whole, and to find coherence. Now one thing that philosophy is really excellent at doing is finding this coherence between beliefs. Now as we talked about two chapters ago, coherence is not enough for truth, but it's very helpful. Coherence is at least necessary for a true belief. The truth isn't going to disagree with itself. But it's not all there is to truth. So with this notion of criticism by asking what justifies our beliefs and having the demand for coherence, we can eliminate at least some error, at least some error. And in that regard, philosophy is useful for the rest of our academic intellectual endeavors.