▶︎ 0:00 Welcome to this class on Immanuel Kant, titled Kant's Three Questions. Immanuel Kant, as I'm sure many of you know, is one of the most influential, maybe the most influential of the modern European philosophers. But he's also notoriously difficult, as a writer and as a philosopher. And he also wrote a great amount, many important works, and it can be hard as a result sometimes to get a good overview of his philosophy, that both allows one to see the overall structure of it and then also to appreciate a lot of the different aspects of the philosophy in sufficient detail, rather than being just overly superficial.
▶︎ 0:47 The aim of this class is to frame Kant's philosophy in terms of three famous questions that he himself poses, in one of his major works, the Critique of Pure Reason, in order to use these three questions as a gateway into appreciating the details of his overall philosophical project. In the Critique of Pure Reason, one of his major works, one of the most famous works of modern European philosophy, Kant lists three different questions that he thinks that his philosophical project is aiming to provide ultimately answers to.
▶︎ 1:29 These are the three questions. First, what can I know? Second, what ought I to do? And then third, for what may I hope? And we're going to start off today focusing on aspects of that first question, what can I know, the way that Kant attempts to answer it in the Critique of Pure Reason and then in other related works like his Prolegomena to Any Future Metaphysics, et cetera.
▶︎ 1:57 When Kant's asking this question, what can I know, what can we know, what he's primarily interested in is what can we know in terms of metaphysics. So the type of knowledge that he's primarily concerned with is metaphysical knowledge.
▶︎ 2:18 And in Kant's day, metaphysics was typically understood in the following sort of way. If you look at various textbooks from the sorts of people that Kant when he was a student was reading, the kinds of textbooks that Kant when he was working at the university would lecture from, what you find is that metaphysics is usually divided up in the following sort of way.
▶︎ 2:49 People will usually start off with what gets called general metaphysics which is oftentimes identified with ontology. And the aim of general metaphysics for Kant's contemporaries was typically to arrive at basic concepts that were taken to apply to all things. To arrive at a set of basic concepts that anything, any possible thing, any actual thing, these concepts would apply to it. The standard examples would be things like finite and infinite. Anything is either finite or infinite, or notions like substance-accident. Something is either a substance or it's an accident, like a property of a substance, or cause and effect, for example.
▶︎ 3:52 And so the aim of general metaphysics ontology was to explain what these sort of basic concepts were that pertain to all possible things, and to analyze and elucidate these different concepts. And then the aim was to take these concepts and apply them to certain particular subject matters that were taken to be of significant importance. In particular, to apply these concepts to the notions of the soul, the notion of the cosmos, and to the notion of God.
▶︎ 4:37 And so this then gave us what they called typically special metaphysics. Special in the sense of being specialized, being something that pertained to a particular domain. In special metaphysics, you would typically get discussions of the soul, including questions about the nature of the soul, whether or not the soul is immortal or not, the soul's relationship to matter, the world in the sense of the cosmos, and then finally God.
▶︎ 5:23 When Kant's asking this question, what can we know, Kant's primarily asking the question in terms of what can we know in relation to metaphysics. What in the metaphysical tradition is or is not something of which we can have proper knowledge. And the position that Kant himself arrives at is that our ability to have metaphysical knowledge is significantly more limited than many of his earlier predecessors had thought.
▶︎ 6:03 In particular, Kant claims that we need to draw a sharp distinction between knowledge relative to experience, so knowledge of objects that can be given to us in experience, and then knowledge of objects beyond what can be given to us in experience. And the crux of Kant's answer to the question, "What can we know?" is that we're able to have significant substantive knowledge, somewhat akin to the kind of claims made in ontology regarding objects of possible experience. In Kant's technical vocabulary that we'll talk about a bit further later, we're able to have synthetic a priori knowledge of objects of possible experience. But, Kant maintains, we're not able to have significant substantive knowledge of things beyond the limits of experience.
▶︎ 7:10 And Kant takes this to entail that we're not able to have substantive knowledge about key issues in special metaphysics. So for Kant, if you ask him, "Is the soul mortal or immortal?" Kant's going to say, "We don't know. Indeed, we can't know." That's the sort of thing that goes beyond the limits of what can be given to us in experience. It's the sort of thing of which we cannot have knowledge one way or the other.
▶︎ 7:38 If you ask Kant the question, "Does God exist?" Kant's going to say, "We can't know." "We're not able to prove that God exists. We're also not able to disprove that God exists. We're just simply not able to have that kind of metaphysical knowledge."
▶︎ 7:58 And so the key move again for Kant here regarding knowledge is to say that our knowledge is restricted, restricted to the limits of possible experience. Within that domain, we can have this significant synthetic a priori knowledge. Beyond that domain, there's a prohibition on knowledge. We can't make substantive claims to knowledge.
▶︎ 8:23 Now, at the same time that Kant is restricting the extent to which we can have knowledge of special metaphysics, it's important to keep in the back of our minds for going forward that for Kant, knowledge is not always the end-all be-all. There's different sorts of mental attitudes that we can take. Knowledge is one of them, but it's not the only one. So Kant will also talk about attitudes like opinion and persuasion and, very importantly, as we'll see later on in the series of lectures, belief.
▶︎ 9:04 And so Kant's ultimately going to make an argument that he, as he puts it, that he denies knowledge, in particular knowledge of special metaphysics, in order to make room for belief. Because what he's going to argue is that even though we can't, for example, know that God exists, that in his view, morality provides us with rational grounds for accepting that God exists in the sense of having a kind of belief or faith in God's existence. Similarly, although we can't know if the soul is mortal or immortal, Kant's going to maintain that morality provides us with rational grounds for a belief or faith in the immortality of the human soul.
▶︎ 9:53 So he's going to try to make a case that we're prohibited in making knowledge claims, but knowledge isn't everything. There's also belief, and in Kant's view, not just belief or an ungrounded belief, but rather this notion of rational belief, that there's a kind of rational ground for belief that yet doesn't amount to knowledge. So this is a striking sort of position for someone to be staking in the 18th century when Kant's living and writing.
▶︎ 10:32 It's a position that's had a huge influence on the subsequent course of modern philosophy. But what is it that drives Kant into this view? What are the sorts of issues and problems and questions that lead him to ultimately adopt this position regarding what we can know and what we can't know?
▶︎ 10:59 And so my main aim in this particular lecture is to outline the various problems and issues that really drove Kant to this position, and helped to motivate the kinds of detailed arguments that he then goes on to provide in the Critique of Pure Reason and related writings.
▶︎ 11:26 Kant publishes the Critique of Pure Reason in 1781. He revises it and publishes a second edition in 1787. It's really standard to refer to the first edition as the A edition and the second as the B edition. So I'll just follow that. If you hear me say A edition, then I'm talking about the first edition. B edition, talking about the second edition.
▶︎ 11:54 In the preface to the A edition, when Kant first publishes the Critique of Pure Reason, what Kant does for us is he provides us with a sort of intellectual history of philosophy. It's very general, very schematic. He's not talking about specific figures. But he thinks that there's a history of philosophy that can be understood in the following general way.
▶︎ 12:33 Kant suggests that philosophers start out pursuing a project that he calls dogmatism. Ultimately, Kant's critical of dogmatism, and as a result, dogmatism has come to take on a negative connotation or sound like a pejorative term. But when Kant's first introducing it, we don't necessarily need to read any negative connotation or pejorative term into it. What he means by dogmatism is simply that these are people who take themselves to have substantive metaphysical knowledge that they are accepting on the basis of different arguments, arguments derived on the basis of the general concepts and categories that they take to be the primary metaphysical concepts and categories.
▶︎ 13:35 The dogmatists are people engaging in this metaphysical project. And standard examples of dogmatists, by Kant's lights, in his own context, would've been people like the German polymath Leibniz, or various followers of Leibniz, Christian Wolff, who in the eighteenth century was probably the most, early eighteenth century, probably the most famous European philosopher, although he's not as well-known today. So these are the kinds of figures that Kant standardly has in mind when he's talking about the dogmatists. The dogmatists build their castles.
▶︎ 14:20 But then a group comes along, namely the skeptics. And what the skeptics do is they cast doubt on the dogmatists' claims to this substantive metaphysical knowledge. They tear down those castles. And they seem to suggest that that metaphysical knowledge that the dogmatists claim to possess is not secure, subject to question and doubt, not something that it really seems like we're able to possess the way the dogmatists thought.
▶︎ 15:05 Kant thinks that when all these metaphysical castles have been torn down by the skeptics, that this leaves people in this position of thinking, "Ugh, maybe we just shouldn't care about these metaphysical questions." The dogmatists gave these arguments. The skeptics put everything in question. Who knows? Let's just leave all of this to the philosophers. Let's let them argue about it. Let's ignore it. Let's just be indifferent to these metaphysical questions or questions of if we can have this fancy metaphysical knowledge.
▶︎ 15:45 And so Kant refers to this attitude as indifferentism. The skeptics are then followed by the indifferentists, the people who look at the rubble of metaphysics and say, "Let's just give up on the project of metaphysics. Let's just leave it to people, maybe some philosophers in their ivory towers, and just move on with our lives." But one
▶︎ 16:15 One of Kant's core convictions is that indifferentism is not a stable position. For Kant, metaphysics is not something that is simply an idle interest of philosophers in their classrooms or in their cloistered university settings. Rather, metaphysics pertains to universal interests and universal concerns such that at the end of the day, we're not really able to be indifferentists in this sense about metaphysics or not to care about metaphysics, its objects, whether we're able to have knowledge of those objects.
▶︎ 17:07 There's two sorts of reasons that we find in Kant for this idea. One reason is based more in theoretical concerns. Kant maintains that we all possess this faculty of reason and that it's part of reason that reason seeks the unconditioned. Reason is always, for any given thing, seeking some explanation for that thing, trying to arrive ultimately at some kind of unconditioned explanation, something like a full explanation, a totality of reasons, for why something is the way it is.
▶︎ 17:54 Kant thinks that this aspect of human reason, where we're always seeking for further explanations, looking for this totality of explanations, is something that ultimately inevitably drives us to ask questions like, "Is there a being like God?" That is at the ground of everything that's created things. Is there something like free will as a first cause of our actions? He thinks it also is what generates the questions about the immortality or nature of the soul. To the extent that it's just part of the nature of our human reason that it drives us for seeking this totality of conditions until we arrive at the unconditioned, there are questions that are of such pivotal concern to human beings, of such existential gravity for human beings, that they're the sorts of questions that at the end of the day, Kant thinks people can't really be indifferent to, whether we're able to have knowledge or not regarding them.
▶︎ 19:12 For Kant, we can't just be indifferent to the question of do we have free will. We can't be indifferent to the question of is it possible for us to know if we have free will or not. Regardless of whether one thinks that God does or doesn't exist, Kant thinks it's hard to be indifferent to the question does God exist or not exist. Whichever way one's answering that question, it seems to be something of really significant gravity for the way in which one might relate to the world or conduct one's life.
▶︎ 19:52 Both based on the nature of human reason and based on these core issues of human concern, Kant thinks that indifferentism is not really an option for us. It's not a stable philosophical position. We'll inevitably be driven back once again to try and figure out the answers to these kinds of questions, and that will draw us back into dogmatism. We end up, Kant thinks, in the history of philosophy with this cyclical process where we have the dogmatists putting forward their metaphysical structures, those getting torn down by various skeptics, period of indifferentism, people not being able to actually be satisfied intellectually, existentially with indifferentism, returning back to dogmatism. The whole process begins again.
▶︎ 20:50 What Kant wants to do is he wants to find a way to get us off this eternal ongoing merry-go-round. In the Critique of Pure Reason, Kant's project is to investigate and examine the nature of human reason, its extent and its limits in order to provide us with a conclusion about what metaphysical questions we could ever hope to have answers to, what metaphysical questions are at the end of the day going to be just perpetually and inevitably beyond the limits where we're not able to have answers to those questions.
▶︎ 21:34 What is it that Kant sees as these skeptical positions that pose these threats to the dogmatists that seem to be continually creating this cycle from dogmatism to skepticism to indifferentism? He's not as explicit as we would like, in the A Preface where he is laying out this cyclical history of philosophy. But if we look at his writings more broadly, there seems to be at least two issues related to skepticism that Kant has in mind here. So one of these issues is related to the Scottish philosopher David Hume. You'll remember a little bit ago I said that one of these traditional ontological categories or concepts was the concept of cause and the related concept of an effect.
▶︎ 22:41 And this was a notion that was used in a lot of traditional metaphysical arguments. So think, for example, of the cosmological argument in favor of the existence of God as a first cause. There's something that exists now. It must have had some cause that brought it into existence. That must have had some cause. It seems at the end of the day that things have to bottom out in some kind of first cause. Call that first cause God.
▶︎ 23:08 Hume had raised questions about the nature of our knowledge of causation. Questions about the nature of causation that had seemed to put deeply in question these kinds of traditional philosophical arguments based on notions of cause and effect. So in particular, what Hume said is Hume said, "Look, there's two ways that we can know things. One way that we can know something is we have some ideas, and we examine the relations between those ideas."
▶︎ 23:49 So let's say that I have the example of the idea of a whale, and I have the idea of a fish, and I want to ask myself, is a whale a fish? And I examine the relations between these ideas, what it is to be a whale, what it is to be a fish. And I see no, a whale is a mammal. Anything that's a mammal is not a fish. So a whale is not a fish. So one way that I can know something is just by examining the contents of my ideas and the relations between those different kinds of contents. A lot of people might think math's like that. Examine the content of the concept of the number two, of the equal sign, of one, of plus, and just see from the relations of the ideas that one plus one equals two.
▶︎ 24:45 The other way that Hume thought that we could know things was on the basis of experiencing them, observing them. And Hume referred to this kind of knowledge as knowledge of matters of fact. So for Hume, we have knowledge of relations of ideas, and we have knowledge of matters of fact. And what Hume did regarding causation in Kant's view is, Hume said, "Consider a standard case of alleged causal knowledge." Let's take the example that if I eat bread, the bread is going to nourish me. Just everyday, totally normal sort of alleged causal knowledge that the bread is going to cause me to be nourished.
▶︎ 25:35 And Hume says, "Do we know this on the basis of relations of ideas?" And the answer is no. I can know what bread is, and I can know what a human being is, but it's not as though just by examining my idea of what bread is and examining my idea of what a human is that I can somehow see that bread will cause a human being to be nourished. Maybe my definition of a human being following the tradition is like a rational animal. How is it part of just the concept of a rational animal that bread is something that's going to nourish it rather than, say, poison it? That's not the kind of thing that we can know just by examining the contents of those ideas.
▶︎ 26:26 Well, then do we know that bread causes people to be nourished as a matter of fact, on the basis of experience? And at first, the answer might seem yes. That might seem like a promising route for this kind of knowledge about bread as a cause of nourishment. But Hume says, "Look, when I'm saying bread's a cause of nourishment, I'm saying that it's necessarily the case that if someone eats bread, then at least all other things equal, it's going to cause that person to be nourished." So I'm making a claim when I make a causal claim to a claim about necessity. To claim to have causal knowledge is to claim to have knowledge about a necessary connection between one thing and another. In this example, a necessary connection between the bread and the being nourished.
▶︎ 27:28 And Hume says, "Am I able to have knowledge of this necessary connection on the basis of experience?" And Hume's suggestion is no, or at least this is how Kant takes him, that it's not the case that I'm able to know there's a necessary connection between eating bread and being nourished on the basis of experience. I have a lot of experience of people eating bread and remaining alive, so I have a lot of experience of people in the past eating bread and it nourishing them, it seems. But in order for this to be a necessary connection, it needs to not just be something that held in the past. It needs to be something that holds in all cases, including all future cases. And I don't have any experience of the future.
▶︎ 28:33 So my experience tells me that at least up till now, when people ate bread, they stayed alive and seemed to be nourished. But Hume says that doesn't guarantee that that pattern's going to stay the same in the future. It doesn't guarantee that it's always going to be the case. And so my past experience doesn't provide me with adequate knowledge that there's actually a necessary connection between the eating of the bread and the being nourished. Maybe things have seemed this way up till now, and then maybe tomorrow we'll all wake up and be horribly surprised. We'll eat our morning toast, and instead of feeling nourished, we'll all get horribly, I hope not, but horribly sick. There's nothing, Hume thinks from our experience that rules that out definitively as a possibility.
▶︎ 29:35 And so the lesson that Hume takes from this and the lesson that Kant takes from Hume here, is the suggestion that there's something deeply puzzling about how we're able to have knowledge of causation, how we're able to have knowledge of necessary connections in the world. And so if you're a metaphysician, who's been indulging in things like the cosmological argument, arguing for a first cause of the world on the basis of claiming cause and effect relations, then this problem raised by Hume, this question of, are we even able to have knowledge about causation, seems to put that kind of metaphysical project into serious sort of question. So this seems to be one of the ways in which Kant thinks that a skeptic, in this case Hume, considered as a kind of skeptic, seems to put in doubt traditional dogmatic metaphysical knowledge.
▶︎ 30:47 Another thing that Kant oftentimes alludes to, when he's talking about skepticism posing a threat to metaphysical knowledge, is the idea that sometimes when we try to address metaphysical questions, say we try to address the question, is the world understood as a universe infinite in size or finite in size, that we find ourselves caught up in paradoxes and contradictions. So the reference point here for Kant is the ancient Greek skeptical tradition of Pyrrhonian skepticism, where you assert something like A, but then it seems like you have equally good reason to say not A. So you assert something like the world is finite in size, but then it seems you have equally good reason to say, "No, no, no, the world's infinite in size."
▶︎ 31:46 And then you get this equipollence, where you have this contradiction where you don't have any reason to favor one or the other of these two. And so in the case of metaphysics, if there's a perfectly good argument in the case of special metaphysics talking about the cosmos, that the world as a whole is infinite, but another equally good reason that no, no, no, it's finite, then you have a contradiction that seems to suggest that there's something totally awry with trying to reach this kind of metaphysical knowledge. This creates another source of skeptical doubt.
▶︎ 32:27 So in his various writings, Kant oftentimes alludes to both of these potential sources of skeptical doubt. He very famously sometimes says that it was Hume's question that led him to the issues in the Critique of Pure Reason. But he also, maybe a bit less famously, claims in his correspondence that it was reflecting on these kinds of contradictions and paradoxes that led him to the Critique of Pure Reason. And so at the end of the day, it seems safe to say at least that both of these streams of skepticism were animating forces, driving him towards the considerations of the Critique of Pure Reason. A third issue that seems to have led Kant
▶︎ 33:20 Into the critique of pure reason, or a third kind of problem that he wanted the critique of pure reason to provide some kind of answer to, is a problem that he first poses about ten years before he publishes the critique, in a letter to one of his former students named Marcus Hertz. In this letter, Kant says the following. He says, "Look, if we're trying to get metaphysical knowledge the way that people like Christian Wolff claimed to have metaphysical knowledge, then we're arriving at these different concepts like substance and accident that are concepts that belong to the intellect. These are intellectual concepts. What is it that makes it the case that we have a guarantee that these concepts accurately reflect the way that reality is? What is it that provides us with a guarantee that these kinds of concepts actually can manage to provide us with knowledge of objects?"
▶︎ 34:40 And in the letter, Kant says, "It seems like there's two ways that we can arrive at knowledge via these concepts. One way that we could arrive at knowledge is where we arrive at the knowledge empirically. We're somehow affected or influenced by the world. On the basis of that experience, we arrive at and obtain certain concepts. And so we can say that our concepts match the way the world is because our concepts have been drawn out of our experience of the world. So if I go in the woods and I'm looking around at the trees, and I see elms and birches and aspens, then I'm having this experience of all these different items. I can derive from those experiences the general concept of a tree by isolating what it seems like all these different objects have in common. And so in that case, it seems like I have a perfectly good guarantee that the concept of tree that I have now is something that matches the way that certain objects are in the world around me."
▶︎ 36:10 But it seems like the kinds of concepts that the metaphysicians are talking about in general metaphysics or ontology are not like the tree example. They're talking about notions like substance, accident. They're talking about notions like causation and necessary connection. And Kant's view is that these don't seem to be concepts that we're able to just derive from experience. Again, think of the Hume case. Hume had said, "Yeah, we've seen regularities up till now," but you don't see a necessary connection between bread and being nourished. All you see is that up till now, when people ate bread, it helped them stay alive. You don't see that it's somehow a necessity that bread's gonna nourish people.
▶︎ 37:07 So Kant says we don't seem to get these substantive metaphysical concepts from our just everyday experience of the world. So that first way that we could guarantee the concepts would provide us with knowledge by tracking reality doesn't seem like an option. There's another way that we might think a representation could be, we can guarantee that a representation was a correct representation of reality. And this would be where the representation itself was the cause of the object.
▶︎ 37:47 So Kant seems to have in mind here a particular sort of conception of God as the creator of the world. God has a representation on this model, a representation of the world and the divine understanding. And God creates a world that matches that world as represented in the divine understanding. And God knows that the created world corresponds to the representation and the divine understanding because God knows that the created world was modeled on that representation and the divine understanding. So in this case, you have a model where you can explain how you're able to have substantive knowledge about the world, where that knowledge is not empirical. God's not being affected by the world or influenced by the world. Where rather that representation, rather than being empirical, is totally intellectual. It's just being contained in the divine understanding.
▶︎ 39:06 But we're not God. On Kant's ultimate view, we don't even know if God exists. And our intellectual concepts like cause and effect, substance, accident, from a just sort of everyday perspective might not seem to be the causes of objects the way the divine mind would be the cause of objects. And so Kant questions whether this could be a route for us to be able to have metaphysical knowledge, given that we're not God, we don't seem to be creators in the same way that God is.
▶︎ 39:51 So in this letter to Hertz then, Kant says, "Look, there are these two apparent avenues for explaining how our notions, metaphysical notions could provide us with knowledge of reality, knowledge of objects. Either the world could influence us, and we could get the concepts from the world, so to say, or our concepts could themselves be part of the cause of the object so that the object has to conform to its cause." But neither one of these seems to work if we're talking about metaphysical concepts, trying to arrive at metaphysical knowledge. Posing the question this way leads Kant into one of his major framing devices for the critique of pure reason and the way that he envisions the project of the critique of pure reason.
▶︎ 40:54 Kant's notorious for having a lot of technical vocabulary. His own contemporaries complained about him introducing new words and terms or maybe using old terms with new definitions or in new ways. But in order to grapple with Kant, it's essential that we have some kind of grasp on at least the fundamental vocabulary that he's introducing and employing.
▶︎ 41:24 The way that Kant frames part of the project of the first critique in the wake of this letter to Hertz is as a question about whether we're able to have what he calls synthetic a priori knowledge. And so what I'm going to do here in the last part of this lecture is I'm going to lay out Kant's notion of synthetic a priori knowledge and introduce the relevant vocabulary and terms for understanding what Kant has in mind here.
▶︎ 42:08 Kant maintains that we have two different, in this context, relevant cognitive faculties. We have a faculty that he calls understanding, and the understanding is a faculty of concepts. And then we have sensibility. And sensibility is a faculty that provides us with a type of mental representation that Kant calls intuition. What's the difference between these two different kinds of mental representation?
▶︎ 43:01 For Kant, concepts are general representations. So if I talk about the concept tree, I'm not talking about any individual specific tree. I'm rather employing this general concept that all individual specific trees fall under. So an aspen, a particular aspen in someone's yard, falls under the concept tree. A particular oak in someone else's yard falls under the concept tree. So the concept is a general representation that all the individual relevant objects can be said to fall under.
▶︎ 43:56 In virtue of what does an individual object count as falling under this concept? Well, this concept includes various, Kant calls them marks, when it's like various little bits of information, where if an object has a corresponding property that matches that mark, then the object counts as an instance of that concept. So it might be part of someone's concept of a tree that it has a trunk, that it has leaves. And so you're looking at a particular object and you're wondering, "Is this a tree?" And so you look to see whether or not the object has properties that match these marks contained in the concept. Does the object have leaves? Does it have a trunk? Does it have all of the relevant marks to count as a tree?
▶︎ 44:59 And, as such, Kant says that concepts count also as what he calls immediate representations, because whether or not a particular object falls under a particular concept is mediated by whether the object corresponds with these marks or not.
▶︎ 45:28 In the case of intuition, Kant says, "Look, an intuition is not a concept. It's rather not a general representation but a singular representation." So if I'm looking right at this object here, this table, then I have a representation, and it's a representation of this particular individual. So the intuition, Kant says, is a singular representation in the sense it's a representation of some particular, like a representation in our example here of this particular table.
▶︎ 46:16 And Kant says that intuitions count as immediate representations. I'm in a kind of immediate mental contact here with this table. That contact is not mediated by asking whether the table has particular features that correspond to the marks of a concept. Just in seeing the table, I'm in a kind of contact with this particular individual here. And so we have in this case what Kant calls an intuition. For Kant, we can understand different notions of knowledge in terms of the relationships between concepts and intuitions.
▶︎ 47:15 One type of knowledge is a knowledge that we can possess merely on the basis of concepts. Kant calls this analytic knowledge. We have analytic knowledge where we look at a concept and we ask whether some predicate is such that it's already seen to be contained in that concept. So if I ask the question, "Is a whale a mammal?" we might say that it's part of the concept of being a whale that it's a mammal. And so the answer becomes yes. And I don't have to do a lot of fancy biological research to figure out that the answer is yes. I just examine my concept of what it is to be a whale. I see that mammal is one of the predicates contained in that concept, and I know analytically that it's true that a whale is a mammal.
▶︎ 48:29 Because I don't have to do a lot of fancy biological research to answer that question, Kant will say that that knowledge is not something that I arrive at empirically by observing a bunch of whales, a biologist does. Rather, it's something that I know in Kant's terms a priori. It's something I know independent of experience, independent of further observation. I just need to examine the contents of the concept to see that this is true. Now, granted, that particular concept is an empirical concept, it seems. So maybe in order to arrive at that concept, I need some experience. But once I have the concept, I don't need to do any further observation. I just need to examine the content of the concept to see that it's true that a whale is a mammal.
▶︎ 49:37 But not all knowledge is analytic. It's not part of the definition of a table that the table's gonna be brown, even though this particular table is brown. So how do we know that this particular table is brown? Obviously, we know that by observing the table, on the basis of experience of the table. Because the predicate brown is not part of the concept table, when I form the judgment, the table is brown, attribute the predicate brown to the table, Kant says that this is not an analytic statement. It's not simply expressing a predicate that's already contained in the concept of the subject of the judgment. Rather, it's what he calls a synthetic judgment.
▶︎ 50:48 I'm taking two different things that weren't already connected with one another, and I'm joining them together and putting them together. The concept of a table is not just of itself connected or related to the notion of being brown, but I'm saying this table is brown. I am connecting the notion of a table with this particular predicate, brown. So any kind of this combining, Kant's general term for that is synthesis. And so what we have here is what he calls a synthetic judgment because we're combining these different representations, the concept and the predicate.
▶︎ 51:32 So then if we look on the board here, Kant asks, "Which of these different types of knowledge are we able to have?" Analytic a priori, synthetic a priori, analytic empirical, synthetic empirical. And Kant says, "Look, we can have a priori analytic knowledge. We can know analytic truths independent of experience." Like in the whale example where we said we know a priori that a whale is a mammal because it's just part of the concept of being a whale that it's going to be a mammal. And Kant says, "Look, we can have synthetic empirical knowledge." That's like the table example. I look at the table, have an experience of it. I see the table is brown. That wasn't part of the definition of table, but on the basis of experience, I know that this table is brown. And so I can know the truth of synthetic judgments on the basis of experience. I can know the truth of synthetic judgments empirically.
▶︎ 52:37 Well, what about analytic empirical? Kant thinks that this is a box that would be a little like, in a way, silly. So I take a standard example of a piece of analytic knowledge, say like a bachelor is an unmarried male. To know that empirically would be to knock on a bunch of people's doors and ask them, "Are you a bachelor?" And for them to say, "Yes," and for you to follow up with, "Are you married?" And for them to say, "No." And on the basis of this experience to think, "Aha, I've arrived at the knowledge that a bachelor is an unmarried male." That obviously would seem like a really pointless thing to do, because rather than taking a day to knock on people's doors and ask them these questions, all you have to do is examine the concept of a bachelor, Kant would say, to see that it's just part of the concept of being a bachelor that one is unmarried. And so this is something that you can know a priori. You don't need to waste your effort knocking on people's doors trying to arrive at this kind of knowledge empirically. So we're just going to ignore this box.
▶︎ 53:56 And then the box that Kant is really interested in is this one. Are we able to have synthetic knowledge a priori? And why is Kant so interested in this box? Because Kant thinks that a lot of traditional metaphysical claims are claims that if we're able to know them, would belong in this box. So think about our stock example here of the bread nourishing the body. If we have the notion of causal relations as necessary connections, and we've said that the causal relations are not things that we can know analytically, like it's not just part of the concept of what bread is that it's going to nourish rather than poison, then it seems Kant wants to say that in order to have substantive metaphysical knowledge of necessary connections, that kind of knowledge would need to be, if we were able to have it, synthetic a priori knowledge.
▶︎ 55:17 Is it the case that every change has to be the effect of some cause? Or could there be just uncaused changes? It doesn't seem like it's part of the concept of a change that it has to have had a prior cause. So if we make a strong claim like every change is the effect of a cause, then we're making a synthetic claim. But are we able to know on the basis of just observation that every change is the effect of a cause? Kant thinks no, that's not the sort of thing we can just know on the basis of everyday observation. It's again one of these claims to a kind of necessary connection that every change is the effect of some cause, not just changes in the past, but changes in the future. There's this necessary element here. And so if we're able to have this kind of knowledge, then it's going to need to be, Kant says, synthetic a priori knowledge.
▶︎ 56:28 And so for Kant, the structuring question of the Critique of Pure Reason, the structuring question of what can we know is this question of what are we able to have synthetic a priori knowledge of? What are we not able to have synthetic a priori knowledge of? And the position that Kant ultimately arrives at is he makes a set of arguments that we are able to have synthetic a priori knowledge of objects of possible experience, objects that can be given to us in space and time. And so to an extent, traditional ontology has something right, something in the ballpark of being correct. Relative to objects of possible experience, we're able to have substantive a priori knowledge, but we're not able to have synthetic a priori knowledge beyond the limits of experience.
▶︎ 57:38 And so that traditional project of trying to take ontology and then apply those concepts to arrive at knowledge and special metaphysics of the soul, the world whole, God, Kant says that is a project that is inevitably doomed to fail. We're not able to have synthetic a priori knowledge of the soul, the world, or God. We're not able to know if we have immortal souls or not, if the world is the sort of thing that has a free first beginning or not, if God exists or not. Thanks.