Aristotle, Physics
Part 1 (Book II, Chapter 1)
MCKEON:1 We now turn to a consideration of Aristotle, and let me begin by making two generalizations. First, there are those who think that because Aristotle was a pupil of Plato, he was, therefore, a Platonist. These people clearly don’t read Aristotle carefully, and they clearly lack experience of the relation between teacher and pupil: the disciple never follows the master. [L!] Consequently, this relationship would be a priori impossible. Second, we will be working with a series of hunks from book II, from book III and from book V of the Physics. They begin with a discussion of nature. Nature is the Latin form of the Greek word phusis; therefore, this consideration of nature is important because it is our subject matter, phusis.
Now, I would like to proceed in the manner that you have learned in handling Plato and, first, to take chapter 1 of book II, which is broken into several arguments. Tell me what it is that Aristotle is trying to do here, and if you like, compare and contrast it with what we’ve done with Plato. Mr. Wilcox?
WILCOX: He seems to be trying to set up a framework with which to start and . . .
MCKEON: That seems to me highly improbable. Let me give you an opposite approach from that. It looks to me as if he’s trying to distinguish and sharply separate three terms or three words: nature, by nature, and natural. That’s not a good answer, either, but it seems to be more nearly related to the text because it deals with what’s there, not with some framework which is hard to get. . . . What’s the first sentence? Tell me what that’s about.
WILCOX: The first sentence is, “Of things that exist, some exist by nature, some from other causes” [192b8].
MCKEON: All right. What would Plato do? . . . Miss Frankl?
FRANKL: He divided all things into those that have a beginning and those that have no becoming.
MCKEON: Those that have being and those that have becoming. And which ones have causes?
FRANKL: The ones with a beginning.
MCKEON: Only the becoming ones. Here, incidentally, in Aristotle’s opening words, the word exist is not a word that the Greeks had a good word for; what he’s literally saying is, “Of all things that are”—tón ontón, “of beings”—“some are by nature, some are by other causes.” Plato divided them into those that are eternal and those that are constantly changing. Aristotle then gives you a division in the next paragraph. What are they divided into? . . . These are the things that are by nature; that’s what we’re starting with. We’re not going to define nature first; that’s too hard. But there are some causes which are natural and some causes which are not natural. . . . Yes?
STUDENT: The things that are natural have an internal principle of motion or an internal cause of production.
MCKEON: What things are natural?
STUDENT: Those that have the necessary means of production.
MCKEON: We’re making a list of natural statements here.
STUDENT: Well, he divides into classes anything that is produced by it’s own internal . . .
MCKEON: Yes?
STUDENT: He says that these things are natural because we say that they exist by nature.
MCKEON: All right. What are the things we say exist by nature?
STUDENT: Plants, the parts of animals, and so on.
MCKEON: Animals and their parts, plants and their parts, and . . .
STUDENT: Simple bodies.
MCKEON: Inanimate things and their parts. Those are all natural; they all have internal principles of motion. What?
STUDENT: It’s funny that you’d write in inanimate things and their parts.
MCKEON: (dropping a book). Did that fall?
STUDENT: Yes.
MCKEON: Is it animate? . . . Is it inanimate? . . . I didn’t push it, but it’s an internal principle of motion. That’s why it’s natural.
STUDENT: Is that what he means by the internal principle of motion, that an inanimate object can gain its proper place, like books?
MCKEON: Well, the internal principle of motion is being in its proper place.
STUDENT: What about fire?
MCKEON: Fire rises, air rises, water sometimes rises. And you need to remember that we’re going to have a lot of kinds of motion. In book II, Aristotle gives an enumeration of all the causes of motion, and nature is one.2 I think I cut that out of your selections; consequently, let me ask what the other causes of motion could be.
STUDENT: Well, others could be necessity, chance, fortune . . .
MCKEON: No, necessity is not a cause of motion. But chance and fortune are; and those two we’ll get more detail on. Then, as opposed to natural motion you have violent motion. If I threw the chalk instead of letting it drop, it would have an external principle of motion. Fortune is something like art or intelligence; that is, fortune occurs whenever you could have done it by purpose. But if you think out something and then make it, that is not a natural object. In fact, we still call it an artificial object: you would use art to make the object. Chance, on the other hand, is something which occurs not by virtue of the internal principle of motion or the art. If, intending to catch the elevator, I walk to one of the buildings on campus which has an elevator, I would be operating according to art or intelligence. If the elevator is operated mechanically, it would be violent motion. If, however, it is operated by an operator, it is motion caused by art; and if I happen to get to the elevator just at the moment the elevator arrives, opens its door, admits me, and takes me up, that is chance.
STUDENT: Fortune, isn’t it??
MCKEON: That’s chance. I couldn’t have planned it. Fortune is something that I could have done if I had known. If, to use an Aristotle example, I go to the supermarket in order to buy a can of beans, see a man who owes me money and collect my debt, that’s fortune because I would have gone there to collect my debt if I knew he was there, but I’d gone there only for beans. But in the case of catching the elevator right at the moment—unless there were a schedule of that elevator, and even that wouldn’t work—, then it would be chance. In any case, what we’re talking about here are the things that operate by nature and this is a list of all the things that will operate by nature. Consequently, biological sciences and physical sciences are all involved; they’re all branches of physics.
Let’s proceed, then, from this to our next question. We’ve enumerated and we’ve specified that we will always want to take the thing in itself. That is, in the case of a doctor operating on himself, this is not an internal principle of motion; this is an external principle because qua doctor he is not identical with himself. It’s different than getting his health back naturally. This brings us, then, to the point that I want to pick on. I want to ask, What’s he try to prove next? Notice, this is a demonstration of what we mean when we say, “by nature”: a thing operates by nature when it’s an internal principle of motion. And let me summarize: nature is the internal principle; to “have a nature” is different from being a nature—a substance has a nature, but a substance is not a nature—; and “according to nature” is anything which happens as a result of these processes. He’s done all of this, and he begins the next paragraph by saying, “What nature is, then, and the meaning of the terms ‘by nature’ and ‘according to nature’, has been stated” [193a1–3]. What do we need now to prove? Mr. Milstein?
MILSTEIN: He’s concerned with trying to prove that nature exists.
MCKEON: We’ve shown what nature is. We now ask whether we should prove that nature is, and we say no. And this, in general, is the position that Aristotle takes. That is, when you are in a science, it is not the function of the scientist to demonstrate that the subject matter exists; he merely analyzes it. There may be another science, frequently metaphysics, that has to do that demonstrating. But it is not the business of the geometer to demonstrate that there is such a thing as a circle or a square or triangle; he just examines their nature.
All right, having done that, we begin in the next paragraph [193a9–11] a more serious inquiry. Mr. Milstein, do you want to tell us what we’re concerned with now?
MILSTEIN: He brings up the discussion of the various ways in which nature is changed.
MCKEON: O.K. What have we gone on to? What are the ways in which anything changes.
MILSTEIN: The first one he calls the immediate, specific nature of matter.
MCKEON: Yes. There are some philosophers who think that’s the whole of nature. We will come to the conclusion that it’s not nature, but it is one of the specifications of nature. The material substrate is a kind of nature that’s unchanging. What’s the other.
MILSTEIN: Shape or form.
MCKEON: All right. What’s the relation between them?
MILSTEIN: Well, form is the nature of a thing; it is, in some sense, that into which something is growing. It is not the something, it’s not the actuality which builds up the shape.
MCKEON: You see, you’re reciting; you’re not giving us the meaning. We want to say that matter isn’t nature, a fairly unpopular position today, although it wasn’t then. We want to say that form is nature in a more definite sense. If we’re going to say this, tell us what we mean thus far by it. What would we mean by this? . . . Part of the argument begins with the statement, “We also speak of a thing’s nature as being exhibited in the process of growth by which its nature is attained” [193b13–14]. Now notice, this is not unrelated to what we were talking about before. Our argument there had to do with what it was we make something out of, such as a bed. What is the nature of the bed that one makes, which is unlike man formed on man? That is the form of the bed. The one, notice, is the process of generation; the other is the process of growth. Therefore, part of the answer to the question of what we will mean by nature will depend on an argument about the nature of generation and growth. Now, what I’m asking is, Can you tell me about it?
STUDENT: Well, nature as form is the end toward which the raw matter tends, and nature as matter needs the form.
MCKEON: Needs?
STUDENT: You have to keep it, you know, formed actually, you have to keep the different parts of the matter in line; but you can’t have the one, an actualizing form, without being in control of the matter.
MCKEON: Well, suppose we were dealing with any process, any change which involves generation or growth. How would we describe it in these terms? . . . In other words, we’re trying to find out what nature is; we’re going to make use of a process, generation or growth. In what sense would a consideration of these lead us to find a shape that is nature. “The ‘nature’ in this sense is not like ‘doctoring’, which leads not to the art of doctoring but to health. Doctoring must start from the art, not lead to it. But it is not in this way that nature (in the one sense) is related to nature (in the other). What grows qua growing grows from something into something” 193b14–18]. It’s that sense that I want you to explain. The same thing goes, of course, for when he gets worried about generation.
STUDENT: Well, if you start with generation and growth and you look at how the bronze grows into the statue . . .
MCKEON: Pick one of the two, generation or growth.
STUDENT: Well, if you’re asking the question about generation, where nature comes in, the bronze isn’t the statue until it has its form.
MCKEON: You’re not talking about natural things, you’re talking about art.
STUDENT: O.K., let’s talk about earth and the difference between earth and bone; he uses that kind of thing a lot.
MCKEON: Look, remember you first asked me if you could begin by taking an instance of growth. The way in which bronze becomes the statue, the way in which earth generates bone, neither of those are common instances of either growth or generation. It’s kind of hard to think of earth becoming bone, even in modern atomic physics. Some of the amino acids we can make, but we haven’t made a cell yet; and until we get a cell made, we can’t make a bone.
STUDENT: Well . . .
MCKEON: In other words, stick to something less imaginative.
STUDENT: All right. Taking the sense in which he mentions doctoring as a process which starts from . . .
MCKEON: Look, look. Begin with a generation or begin with any change—if you don’t like growth, begin with a change of quality—and tell me how shape and matter comes in.
STUDENT: O.K. I’ll start with a change of birth to old age.
MCKEON: I’ve never seen that happen. In other words, deal with a process that I can recognize.
STUDENT: I’ll stick with a little boy growing up.
MCKEON: All right. Joe was two feet tall and became three feet tall . . . . Is that Joe? [L!]
STUDENT: He’s just bigger.
MCKEON: I know, but that’s what growth is. Growth is an increase in size; and when you grow you don’t change your nature, you change your size. If you put on twenty pounds, for example, your nature will remain the same but the scale will act differently.
STUDENT: I don’t see . . .
MCKEON: Yes?
STUDENT: The difference between matter and form is that the matter is a necessary condition or material condition for form, but it’s not nature because if it were, it would be like an element in only having a physical . . .
MCKEON: Nature is going to enter into one of the principles of motion and, therefore, be the beginning of a process.
STUDENT: The material principle of motion would be considered any matter, as he said, any material substance or substratum as having a principle of motion. But the point is that form itself, as he says, exists and is the difference between existing in potentiality and existing in actuality.
MCKEON: But you still haven’t sold me the notion that form is nature.
STUDENT: Well, form is nature in that by this distinction between potentially and actually existing, this thing will exist more fully when it exists actually than when it exists potentially, and by its movement or by its particular way of growing this thing exhibits itself. That is, the illustration that would illustrate better what I’m saying is that to call a frog a frog because of the way it moves or the way it . . .
MCKEON: This might give us a good dictionary if I were trying to call a horse a horse.
STUDENT: We think that the form is the nature because of the relationship between how we identify what is and . . .
MCKEON: Let’s take art here as an example very much like nature. Suppose I dealt with a change of quality which is involved in writing hard on the blackboard. What’s the form that governed this change?
STUDENT: The doctrine.
MCKEON: No. What was there after I got through that wasn’t there before I started?
STUDENT: The chalk marks.
MCKEON: Yes, the white marks. What is the matter that was involved in that process?
STUDENT: The chalk.
STUDENT: The idea used.
MCKEON: The blackboard. If the blackboard wasn’t there, I wouldn’t have been able to put the chalk marks on it. The matter is what remains continuous. That is to say, if you wanted to draw a picture there, the matter is unchanged: it is the potentiality of the change. If the blackboard weren’t any good, I wouldn’t be able to write on it. The form is what is acquired. What’s the name of the place I started? . . . Let me read you the end of this chapter. “’Shape’ and ‘nature’, it should be added, are used in two senses. For the privation too is in a way form” [193b19–20]. What does that mean?
STUDENT: A privation.
MCKEON: It’s a privation. All right. Alteration is a change of quality; it was a change from the black to the white marks. I had to begin with the absence of the white marks, and you achieve that happy state by erasing the blackboard—there are always people who are writing on the blackboard. I needed the privation. The matter, the blackboard, had to be there and continue to be there. If it were destroyed as I went along, you wouldn’t be able to read it. What is acquired is the form. If this occurs, as it does in the fall, when the green leaves turn yellow outside our window, this is an alteration. In order for that process to occur, you need the privation, which is green; you need the form, which is yellow; and you need the leaf, which is the matter. And the principle is internal because things that happen within the metabolism of the tree lead to this happy occurrence at this time of the year. Isn’t this very simple?
Notice, the same thing is true if we had local motion, say, local motion on a plane surface like a road. What you would need would be matter. And bear in mind, this is what he will mean all the way through by matter: he does not mean stuff, he does not mean three-dimensional extension or anything like that; he means, rather, the potentiality of a change. Consequently, the matter in this local motion would be a plane surface. The privation would be there where you started from and the form that is acquired would be here where you ended up. You go from there to here on a surface, and this is the analysis of local motion. As he says in the last sentence [193b20–22], when you get to generation you’ve got some problems; but they are metaphysical problems, and generation isn’t treated in physics, anyway.
Well, this is the point from which we’ll begin our next discussion. Next time, having initiated you into the niceties of the Aristotelian analysis, I will go more rapidly. Begin with chapter 2, and if you’re really on your toes, we might even finish Aristotle and get up to the modern form of this problem.