 But what I want to do today, I have a rather difficult task. I want to try to show that the praxeology by that actually means the science of human action, but it's sometimes loosely used to mean the method that's employed by Mises and Rothbard and other Austrian economists in their work is quite easy to understand once you take note of a few basic distinctions. Many people say when they read the first or try to read the first 140 pages of human action, find it extremely difficult going. They say, oh, I want to go on to something else. This is too hard. But what I want to attempt to do in my rather boring fashion is to show that this is actually fairly easy to understand. So I want to start by making a distinction between concepts and judgments. A concept is an idea that we have of something. Anything that I'm thinking about, the object of my thought, for example, I'm thinking about this lecture, I'm thinking about particular people in the audience. Anything that I'm thinking about is a concept. Notice that a concept doesn't have to be about an idea. The concept is an idea, but it doesn't have to be about another idea. I could say I have a concept of this audience, but that would be different from saying I have a concept of the idea of the audience. So very important, because people will see a bit later how this can lead to mistakes, that to realize that when we're talking about concepts, such as the crucial concept, the concept of human action, we're not talking about ideas in our minds. The concept is an idea in our mind, but it's not about something in our mind. We'll see why this is important later on. Now, judgment is an assertion or denial of something about a concept. For example, I suppose I say this audience is larger. This audience is making me nervous, because there are so many people here. That would be a judgment. I would be saying something about a concept. According to one view of judgments, judgment is a concept that is two concepts, unified, that are brought together by is or is not. That's called the two names theory of judgment. That was very popular among some medieval thinkers. There's some modern logicians, such as Fraga, the great 19th, early 20th century logician, said no, no, that's all wrong. You shouldn't say that a judgment is just linking two concepts together by is or is not, that the predication is completely different from that. But we don't have to go into that now. The important thing just is to realize that judgment is saying something about a concept. And a proposition is expressing a judgment in words. So a proposition, judgment, or sentence, I'll sometimes use one rather than the other. But I won't be really making a big distinction between, but it's just important to realize that the judgment is saying something about a concept. Now, one of the concepts that we have is the concept of action is the use of means to achieve an end. And by action, we usually generally mean some kind of physical movement. It doesn't have to be a physical movement, for example. Suppose I say, all those who agree with me, please signify by remaining seated. Well, nobody stood up, so you've all agreed with me. So that's an action. But most actions aren't like that. They involve some kind of physical movement. So once we have a notion of action of using means to achieve an end, we can think about it and ask what's involved in the concept. This is, say, we can ask what, this came up in the previous lecture, what is involved in action? We're choosing, we have a scale of preferences in which talking to me doesn't rank very high, apparently. So we have to ask what is involved in the notion of how does choice figure into action? And we answer that just by thinking about the concept of action. We have knowledge of this concept. We have this concept, and we can figure out what's involved in it. So this is a deduction. We're deducing what's involved in the concept, but it's an informal kind of deduction. It's not, say, if you've taken mathematical logic, it's not something where we're setting out some kind of formal system and then coming up with proofs for propositions about the system, where we derive them through some kind of rules. At every step, we have to know what we're, understand what we're doing. We can't just carry out rules as we do in mathematics and figure things out just by mechanical application of rules. This has sometimes led to people misunderstanding praxeology. For example, one of the reviewers of Human Action was writing an American economic review and said, if Mises is supposed to be trying to come up with a deductive science of economics, why doesn't he just put all these propositions in the form of mathematical logic then we could see whether the deductions really follow. But as Murray Rothbard pointed out in a reply to this critic, that isn't the kind of deduction that's involved in praxeology. Here, we have to understand every step. Now, we can have the concept of action, which is use and means to achieve an end. But how do we know that there are actions? Mises has a very interesting answer to this, which I think is a quite profound one, philosophically interesting one. He says, we wouldn't be able to make sense of our experience without the concept of action. Suppose we didn't have a concept of action. Well, then we could say someone could see various physical motions. We could see people moving around or we would see just say as we watch, physical objects might move. We wouldn't understand what they were doing unless we had the concept of action. So if we don't have this concept, we just wouldn't be able to know what people are doing. And Mises calls action. Now, this is one of the key terms that always leads to trouble. He calls this an a priori concept. What he means by this is it's a necessary condition for understanding this part of experience. He's saying, unless we have the concept of action, we wouldn't be able to understand what people are doing. We would say if you saw people, say you go into this, imagine someone going into a store and someone is paying for a book by handing over money to the cashier. If you didn't have a concept of action, you wouldn't understand at all what's going on. You would just see someone, you would see various physical motions taking place. Someone would be handing someone else a certain object, but you would have no idea what was going on. It would just be imagine say you were looking at, you were a physicist looking at certain physical particles. You would just be able to describe the motion of these particles, but you wouldn't understand the transaction. You wouldn't understand the sale in any other sense than seeing that physical motions were taking place. So you have to have this concept of action in order to understand what's going on. So when Mises says that an a priori concept is needed to understand something, this is a logical requirement, according to him, is to say one more time, we wouldn't be able to grasp what's going on unless we had the concept. Now this isn't, this is a point a lot of people get wrong. This isn't a point about whether concepts are biologically innate. You remember there was a Descartes thought that we're born with certain concepts and the British empiricists such as John Locke denied this. They thought that we don't have concepts, all concepts are required from experience and this kind of dispute is still going on today. There are various people who claim we have innate structures in our mind. The linguist Noam Chomsky thinks this, the psychologist in philosophy, Jerry Fodor, other people deny it, but this isn't what Mises is talking about. What he's saying is regardless of how we got the concept, we have to have this in order to understand experience. One reason it's very important to distinguish this view that this is a logical requirement from saying a concept is innate is suppose we said that a concept is innate, suppose we said that people just have this innate structure in the mind or brain or something that they have to see various behavior under the concept of action. Then we could ask, how do we know there really are actions just because we were born with certain concepts, maybe they don't correspond to reality at all, just the fact that a concept is innate really doesn't give us good reason to think that it gives us access to reality. But Mises point is differently saying, look, we're able to understand certain aspects of experience and we couldn't do that unless we had the concept of action. So it's a priori in this sense, not in the sense that it's innate. Now, here's, remember at the beginning of the lecture, I distinguish between concepts, it was an idea of something and a judgment, which is a assertion or denial of something about a concept. So it's very important to, we have to distinguish between a priori concepts and a priori judgment. Remember, the a priori concept is one that we have to have in order to make sense of certain aspects of experience and Mises thinks action is an a priori concept. But an a priori judgment is something else. An a priori judgment is one that can be known to be true just by thinking about it. If I think about the a priori judgment, I can grasp right away that it's true. And it isn't, because I can see the grasp but it's true right away, it isn't open, it can't be overthrown by future experience. Once I've got it and I see it's true, that's it. For example, suppose I, let's take the judgment, Aristotle couldn't have been a piece of tissue paper. That we can think about, we can understand that's true. We don't have to go out and test it and try to find out, well, are there people who thought Aristotle was a piece of tissue paper? What's the evidence for that? We don't have to do that, we just understand that the proposition is true. And one thing, one reason I picked that is that examples, it shows another point about a priori judgment, that an a priori judgment doesn't have to consist of a priori concepts, although it can. For example, the one I gave at Aristotle couldn't have been a piece of tissue paper. Well, neither Aristotle nor a piece of tissue paper is an a priori concept. Neither of them is something that we have to have in order to make sense of experience. Aristotle, we learned about Aristotle and tissue paper just by looking at the real world and their empirical concept, they're not a priori concepts, but nevertheless, we can have an a priori judgment about them. We now come to another point in distinction. The great German philosopher, Emmanuel Kant, who I ran referred to as the machine gunner of the mind, distinguish two kinds of judgments. This is different distinction from this one. This is not the same as a priori judgment. He said, there's analytic judgments. In an analytic judgment, the predicate is contained in the subject. And what did he mean by that? Well, let's take the statement, all bachelors are male. Well, the definition of a bachelor is an unmarried male above a certain age. So if you say all bachelors are male, well, male is part of the definition of bachelor. So Kant would call that an analytic proposition because the predicate is contained in the subject. And so you can see analytic judgments are a priori because we can know they're true just by thinking about them. We don't have to ask, are all bachelors male? We don't have to do a survey say, oh, I found a bachelor who turned out not to be male. We just grasp just from the definition that it's true. And on Kant's usage, if a judgment isn't analytic, it's synthetic. So all judgments are analytic or synthetic just because he's defined a synthetic judgment as one that isn't analytic. Okay, now the logical posivists who were a group of philosophers in the, flourished in Vienna, early 20th century, had a different account of analytic and synthetic judgments. And it's very important to get how their view was different from Kant's because it was their view that was used to criticize the Austrians, but we'll see their view is much more open to doubt than Kant's was. On Kant's view, every proposition is analytic or synthetic because he set up the definitions that way. Analytic one is where the predicate is contained in the subject, and the synthetic one is anything that isn't analytic. So you see it's guaranteed, if you have a judgment, it's going to be either analytic or synthetic. But the logical posivist account is different. They said that all meaningful propositions are either analytic or empirical. And analytic proposition is, as they took it, it's quite similar to the way Kant did. They said it's analytic proposition, what they call tautologies. And a tautology is either a definition, part of a definition or a law of logic. And they took definitions to be conventional, meaning that people just got together and agreed on what the definition of something was. Suppose we say the four bachelor is an unmarried male. Well, that doesn't really tell you anything about the world, that's just saying people agree to use the word bachelor to mean that. Actually, that isn't that great a definition. I mean, we say bachelor is an unmarried male above a certain age. Well, what we say, call the pope a bachelor, probably not even though he's an unmarried male above a certain age. So it's very difficult to come up with precise definitions of terms. This is, I think, a problem with the logical posivist and with other people. Sometimes people will tell you, oh, well, what you have to do in arguments is define your terms. This is the key, people don't define their terms properly and this leads to trouble. Now, it's certainly right that people sometimes argue it cross purposes because they're using words in different ways, but actually very few words have precise definitions. So it's very, that advice define your terms really isn't, usually isn't worth very much because most terms don't have exact definitions so the advice doesn't help you very much. But to return to the posivist, they said analytic propositions which are topologies and the other meaningful kind of propositions besides the analytic ones are empirical propositions that can be either true or false and we have to find out by experience whether the proposition is true or false. For example, suppose I said Donald Trump will win the presidential election, that's an empirical proposition, we'll find out in November whether that's true but it isn't something I could just think about and see whether it grasped but it's either true or false. I would just have to find out by examining the world. So in the way the posivist had it, we have these topologies, these propositions that are meaningful but really don't tell you anything about the world and then we have empirical propositions that can be either true or false and we have to find out which it is by looking at the world. Now, the problem for the posivist is, which shows it doesn't apply to Kant, is remember on Kant's account all propositions are either, judgments are either analytic or synthetic while it's guaranteed that that's true because he's defined synthetic as not analytic so it follows logically that all propositions or judgments are either analytic or synthetic just because of the way he's defined synthetic but in the posivist view, we have all propositions or meaningful propositions are either analytic or empirical. Well, it's not guaranteed that those are the only two kind of propositions. How do we know that there are meaningful propositions that are neither, that there aren't meaningful propositions that are neither analytic nor empirical. It's not guaranteed just by the way the posivist set up this dichotomy between the analytic and empirical that all meaningful proposition fall under one of the two categories. So if you accepted what they say, they ruled out the way Mises proceeds in human action, they just ruled this out just by fiat. They're saying we don't even have to consider this because Mises claims their propositions that we can get knowledge about the world, about action just by thinking about it, but we don't have to test out what we come up with. Our propositions aren't, the economics aren't just empirical hypotheses that we have to test out. We know them just by thinking about them. So the posivists have ruled this out. They say, look, unless you say that all the propositions of economics or tautologies, in which case they're not telling us anything about the world, they're just conventions, they're just saying how Mises and others propose to define certain terms, unless they're tautology, and the propositions to be meaningful have to be just hypotheses about the world, but so what Mises says is just ruled out from the start, but we can see that the way the posivists have set this up is arbitrary because they've just said that these are the only two kinds of meaningful propositions, analytic and empirical, but they haven't given us any argument that there aren't meaningful propositions that are neither analytic nor empirical. Now, just to go over again, because I know this is a complicated subject, at least I find it complicated, an a priori judgment doesn't have to be about what's in your mind. It's, say, to give that example I gave before, Aristotle could not have been a piece of tissue paper. That isn't a proposition about something in my mind, that's a proposition about Aristotle, and the propositions of economics, when we're talking about action, we're talking about actions in the world, not ideas that people have or just what's in their minds, and the other point I think is very important is that the a priori judgment is true. Remember, it's a judgment that we can know to be true just by thinking about it. Well, if we can know it to be true by thinking about it, then it's true. So some people, they're not wrong to do this, but they're just using a priori in a different way, just use a priori to mean something that you come up with without evidence and then test out. So they would take a priori judgment just to be a hypothesis. Sometimes followers of the Austrian philosopher, Karl Popper, will talk about the conjectural a priori. Well, you can see this is not what we mean by a priori here because if something is a priori, then it isn't a conjecture, it's true. If it's not true, it's not a priori. Another point to bear in mind is a priori doesn't mean the same as deduced or logically deduced, although we can get a priori propositions by deducing them from other a priori propositions. Suppose I say, as we do in praxeology supposedly say, action involves the use of means to achieve ends and we can deduce a notion of a person's preference scale and then deduce various propositions about that. So here we're starting with a priori truth and then deducing other propositions from it, but just the fact, it wouldn't be enough to get an a priori truth that we have some logical deductions from a set of axioms. Sometimes in standard economics, the economists will set up models and then they'll have deductions from them, but they aren't a priori truths unless the axioms are a priori true. Just having a deductive system isn't sufficient to get you to a priori truth. This is sometimes a very common confusion. Sometimes people will object to praxeology. For example, David Friedman, who is a Chicago-style economist and libertarian is objected to a priori reasoning in economics and he gives this example. He says, well, in geometry, we have there's Euclidean geometry and there are non-Euclidean geometries and both Euclidean and non-Euclidean geometries are consistent set of truths derived from different axioms. So he says, look, well, if you wanna know which is true, you can't decide that just by looking at the set of deductions, you have to examine the world and see which one of the geometries actually applies to the world. Now, what's wrong with this objection is if we have to examine the world to find out whether either Euclidean or non-Euclidean geometry applies to the world, then neither Euclidean nor any of the non-Euclidean geometries is a priori true. What he's done there is confuse the deductions from an axiom with a priori true. So that objection doesn't work. And besides, he was unsound on Murray Rothbard and many other issues. That was supposed to be a joke. You have to laugh. Now, I now want to get to what I think is an interesting misunderstanding about what Mises was doing in his, when he spoke about a priori science of economics. And I find every near, I think practically, I think every year that I've been here and I've been around here for about 30 years, there are people who will always raise this point. They'll say, suppose Mises is right about his deductions, there is what he says about action. How does he know that this, what he's deduced applies to anything other than his own thoughts? How does he even know that there are any other people? How do it, maybe all he's come up with is a set of a priori truths about his own thinking. What is essential to grasp, and I think this is, is that Mises, although he had a very strong interest in philosophy, and he certainly was read much more philosophy than most economists, he wasn't, he was an economist, not a philosopher. He wasn't trying to solve the problem of skepticism or the problem of other minds. Say we have, those who've taken philosophy classes will be familiar with a kind of issue like this. Supposing, I think I'm now giving a lecture, but supposing I wasn't supposing, I was just a brain and a vat, and scientists were applying electrodes to my brain in some very unusual way, so I would have the experience that I'm now giving a lecture. Could I know that that's false? Well, that isn't a problem Mises was trying to solve. He isn't starting just with his own thoughts and saying, how do I know anything else? Economics is one of the sciences, and in the sciences, we take existence of the world for granted. Say physicists wouldn't say, well, we're looking at, we have various measurements that we're taking of the physical particles, but how do we know there really are such things as physical particles, or how do we know there really is a physical world at all? That isn't a question addressed in the sciences. Similarly, supposing say someone said, I think Austrian business cycle shows it's likely that the present US economy is not going to be able to sustain full employment for very long. We're going to get into recession. It wouldn't be a good objection to say to someone who said that, oh, but look, you haven't even shown there's such a thing as an economy at all. How do we know there is a physical world? This wouldn't be part of economics. So this, we see, this kind of common sense here where we just accept the existence of the world isn't something that Mises is rejecting. He's not talking about his own thoughts or just about his own thoughts. He's talking about the actual world, and he's not trying to solve the philosophical problems of skepticism. Now, I now want to turn just to a couple other points that I think are important understanding praxeology. Mises makes the rather striking claim that all action is rational. This sounds, when you first hear it a bit doubtful, and don't we know many irrational people such as I would certainly qualify by most accounts of rationality. But Mises has in mind a very weak sense, by weak, I mean, undemanding sense of rational. All that's required is that the actor believes that the means he selects will enable him to achieve his end. For example, we could imagine, say someone who has an enemy and say makes a little wax doll of the enemy and sticks pins in the wax doll, and he's hoping to harm the enemy. So we could say, well, that person doesn't have very good ideas on how to harm people. His ideas aren't very well supported, but what he would be doing would still be rational in Mises sense because as long as the person believed that that would help him attain his ends counts as rational. So because Mises has this weak view of rationality, isn't demanding in what he requires of rationality, he isn't vulnerable to difficulties about rationality that have been raised by behavioral economists. The behavioral economists, the famous ones, Tversky and Kahneman, they were actually psychologists who were winning, Kahneman received Nobel Prize in economics and there are others like Richard Thaler, Cass Sunstein. They've raised criticism, they say, well, people act in irrational ways and they say, economics assumes rational action, but people don't always act rationally. So they have in mind something like people make various kinds of logical mistakes or informal errors in reasoning. But I'll give you one example. Supposing that somebody would be willing, wants to buy a lamp and he would be willing to go 20 minutes to a store that offered the lamp $10 cheaper than another store. So he'd make a car trip of 20 minutes to save $10. Now let's suppose the person is thinking of buying a car and he wouldn't travel 20 minutes because another dealer offered the car $10 cheaper. So some of the behavioral economists will say, well, that's irrational because if it's worth it to you to go 20 minutes to save $10, then you should act the same way in both of these transactions. It doesn't make any difference what percent of the sale price $10 is $10 is $10, why should that matter? Well, that may be right according to certain views of rationality, but that isn't what Mises has in mind. He has just much weaker notion of rationality where it just involves use of means to achieve. And so as long as the actor thinks that's going to help him achieve his end, it counts as a rational action. Now in the time remaining, I wanna mention a couple sources of opposition to economics. People don't accept the way Mises and Rothbard practice economics. They don't like praxeological reason reading, but if they do like it, they think it's wrong. And one source of opposition to economics, and this was one that the positivist held, was that the way we attain knowledge is by following the methods of the physical sciences. Logical positivists were primarily interested in getting rid of what they considered bad metaphysics. They said they're various philosophers who claim that they understand the world just by thinking about it. Hegel might be one example. I said, well, this is all wrong. The only way we can acquire knowledge is through the methods of the physical sciences. So they said praxeology is supposed to be deductive science of action. It isn't following the methods of the physical sciences, so therefore it's unscientific and should be rejected. And Mises, I think, had very effective responses. You can see this in his book, Ultimate Foundation of Economic Sciences. He said, this isn't a good way of proceeding. You shouldn't insist that the subjects, if you say what scientific, you shouldn't insist that you have some kind of preconceived idea of what scientific method is, and then say only this method is scientific. You have to look at what the actual sciences are. And if you do that, you'll see that economics counts as one of the sciences. And he thought the positivists should have taken account of economics. So it's rather interesting. Here, the positivists, logical positivists were criticizing him for being too a priori. They say he's not coming up with testable propositions, but he's reversed the criticism. He said, look, these positivists have an a priori idea of what science is, but they should really look at the sciences. They should be more empirical and look at what the actual sciences are. And they find that economics is one of them. Now, another source of opposition, not only to praxeology, but to economics in general, was the Prussian or German historical school. And what they said was that economics can't arrive at general laws, or at least not until collecting a very large number of facts and they never thought that they had collected enough facts to try to come up with laws. And the members of the Prussian historical school supported state intervention in the economy. And this was one of the motives for their opposition to economics. They said, well, if our economic laws, then these laws might show the measures we favor like tariffs and minimum wage laws wouldn't achieve their purpose. They wouldn't be successful. So the solution to that is to get rid of economic law. So they said, instead of saying, well, the economic laws as our measures won't work, they said, let's get rid of economic laws. That's, so they said, so that was one reason they opposed economic. And there's even more extreme version of the view of the historical school, which is called, means is called polylogism. And this is the view that all knowledge, not just economics, is relative to race or class. For example, Marxists think that knowledge is relative to economic class. So they would talk about proletarian history or proletarian physics as opposed to bourgeois physics and so on. And similarly, the Nazis thought that knowledge is relative to race. So that Nazis would condemn Einstein's theory of relativity as Jewish physics. So they said, knowledge is relative to race. And according to Mises, the motive for polylogism is similar to what he thought was the motive of Prussian historical school. That it's opposition to the conclusion of economics because what he pointed out was, although the theory of polylogism is supposed to be opposed to claiming that all knowledge, not just economics, is relative to class or race, in fact, the people who profess these views don't really put much emphasis on anything other than economics. So he viewed polylogism as another more extreme version of the way to attack economics by saying that there aren't general economic laws. Well, I think we're out of time now, so thanks very much.