Introduction to Philosophy & Logic (1999)
Lecture 16: Porphyry's Five Names: Genus, Species, and Difference

Transcript
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As a philosopher, what is my good? I might say it's truth, right? But is truth my own good? As a philosopher, in what sense of my own? Yeah, it's a common good, right? A common good, in the strictest sense, is a good that can be shared by many at the same time and with no diminution, right? So if I understand the Pythagorean theorem, it doesn't prevent you from understanding it, right? If anything, my understanding of it might be a help, you know, to your understanding, right? But if we have an apple pie in common, right? If we, you know, put our money together and buy an apple pie, then we can't be sure that no one of us is going to get the whole apple pie, right? Okay? So that's not a common good in the fullest or most perfect sense, right? Okay? Or if we have, let's say, a computer in common, right? But we can't both, what? Use it at the same time, right? Or we have a chair that doesn't belong to me, you can sit in it too, either one of us can sit in it, but we can't both sit in it at the same time. But truth is very much, in a very perfect sense, a common good, because my knowing a truth in no way prevents you from knowing that truth. If anything, it can be a help to your coming to know it, right? And the same way with, if it's already God, right? The first truth, my knowing and loving God in no way prevents you from knowing and loving God. If anything, it should be a help to your knowing and loving God, huh? Okay? And it's interesting that my greatest goods, like truth or God himself, right? My greatest good is not the good that belongs to me alone, right? Okay? And the same way, you know, as a parent, our greatest good is our children, huh? Okay? And as a citizen, you know, the common good of the country, right? As a member of the basketball team or the football team, the victory, right? But victory is a good that we all, what? Everybody on the team shares in, right? Okay? So, my good as a member of the team is victory in the second sense of my good, right? So, it's very important to see that distinction, huh? Otherwise, when you defend your country, say, you wouldn't be acting for your good. You'd be simply a slave or something, right? When I defend the truth in the way of defending my good, but not my private good, right? A lot of people are stuck on that first meaning of my own, huh? That's why it puts it in the form of an objection, because at first, you know, people don't see a way out of that, huh? And because they're kind of stuck on the first meaning of my own. So, that's the solution. But as I say, it's a important distinction for other parts of philosophy as well as for logic, huh? I have a question on page 5. I wonder if there's a problem in the text, maybe a typo or something, trying to figure out. Page 5, the second full paragraph, beginning to roll we all in. Okay, then a couple sentences down where it says, induction shows. Induction shows that. Is a we missing there or something? Induction shows that. Yeah, the we, yeah. Is it we? Or do we define? Yeah. Elapsis is the kind of good saying. That was an example of induction. Yeah, yeah. Okay. And notice there, at the end of that section there, the next paragraph, you know, when I call a dog an animal, am I calling it by its own name? Yeah, yeah. Because the dog is an animal, right? Yeah. Okay? But it's not its own in the sense that it's the name that distinguishes a dog from everything else, right? Cat and horse and so on. So, we're going to define a thing by its own names in the second sense of its own, right? But that means then names that are common to it and something else, right? Or a name that is said of many things, right? Okay? Now, I say name's said of many things, huh? The word many here has, you know, two meanings, huh? Sometimes we oppose many to few and sometimes many to, what, one, right? So, when I say it's a name said of many things, I mean many as opposed to one, right? It's said of more than one, right? Now, if you think about the word definition itself, it comes from the Latin word finis, meaning end or limit, huh? And the Greek words for definition like horos, huh? And horizmos, right? The word horizon. They come from the Greek word for limit or end, too. And this fits, in a sense, what a definition is supposed to do. It's supposed to put, as it were, draw a line around, right, the thing you're defining and separate it from everything else, huh? And just as the city limits of, let's say, Worcester, right, should contain every part of Worcester within them, right? But no part of any other surrounding town, right? So, likewise, the definition of a thing should draw a line around that thing and separate from everything else, but not include anything else within it, huh? So, it's a very precise idea, the idea of limit, huh? It contained neither more nor less than that of which it is a limit. And, you know, if you go back to the Latin, you know, it had a cognitive meaning in daily life, huh, where a farmer would define his field when he put up, what, a fence around there, right, huh? Okay? And that fence should fence in only my property, right, and not anybody else's property, okay? But the question is, then, how can you define a thing by names that are common to it and, what, other things, right? That seems to be contrary to what a definition is supposed to do, right? It's supposed to fit just this one thing, and if you form the definition by names that are common to it and something else, how are you getting something that fits just this one thing? What's the solution to that problem? Yeah. The combination has to fit just that one thing, right? Okay? So, when somebody tries to define something, huh, you often see, you know, Socrates will see if the definition and the thing being defined are what they call convertible, right? Okay. Now, convertible in logic has a different meaning than convertible instead of the automobile, right? Okay. A and B are said to be convertible if every A is a B and what? Yeah. Yeah. Yeah. And the definition should be convertible with the thing being what? Defined, right? So, if equilateral and right-angled quadrilateral is the definition of square, right? Then every square should be an equilateral and right-angled quadrilateral, and every equilateral and right-angled quadrilateral should be a, what? Square. Square, right, huh? So, you'll see sometimes in the dialogue, Socrates turning around somebody's definition, right? To see if it is in fact, what? Convertible, right? Sometimes in class, you know, I ask the student, what is a chair, right? And maybe they'll come out with something to sit on, right? They say, well, every chair is something to sit upon, right? But is everything to sit upon a chair? Because a bench might be something to sit on, a saddle? But these are not chairs, right, huh? So, you have to add something before this speech is convertible, right? That's one thing you check, right? It's kind of the first thing you expect of a definition, is that it'd be speech that is convertible with the thing being, what? Defined. And I make an interesting comparison there to pinpointing, you know, a target, let's say you want to bomb a target or you want to go someplace, and you give the longitude, and you give the, what, latitude, right? And if you stop and think about it, the longitude is really a line, right? And there's on that longitude as many points as you want. So in a way, to give the longitude of a point is to give what it has in common with an infinity of other points, right? Now how does that help you to pinpoint something, right? By telling what it has in common with an infinity of other points. Seems crazy, doesn't it? And likewise, the latitude is what that point has in common with an infinity of other points, right? But there's only one point that has both that longitude and that, what, latitude, right? So it shouldn't be so surprising, you know, that in a definition, right, you can, what, have a combination of names, right, that fit only one thing, right? So going back to the example there of the definition of square, quadrilateral is a name common not only to square, but oblong and rhombus and rhomboid and topezia, right? And equilateral is a name common to the square and the rhombus, like a jerk square, you know? And right-angled is common to the square and the oblong, right? But the combination of these, equilateral and right-angled, quadrilateral, seems to fit only, what, the square, right? Neurostyle's talking about tragedy and comedy, right? And the epic there in the beginning of the poetics. And he takes the example of the great epic writer, who's Homer, right? And Sophocles is a great tragic writer. Neurostophanes, the comic, poet, right? And he says, well, Homer and Sophocles have in common that they represent great men, huh? The downfall of great men and so on. But Sophocles and what have in common that they represent things as acted out rather than simply narrated, right? Okay. And then he starts to combine these things, right? So the definition of tragedy, there'll be something in common with epic, right? Representation of serious things of men greater than us, right? And something to have in common with comedy, right? That it represents things now, not simply by narrating them, but by acting them on the stage and so on. But the combination of these differences are going to fit only what? Tragedy, right? So I started to define tragedy as a likeness of an action or course of action that is serious, complete, and of some magnitude. In sweetened language, right? Acted out rather than narrated, right? But acted out as a common comedy, as representation of an action that is serious, complete, and of some magnitude, with epic, right? But the combination of the two fits only what? Tragedy, right, huh? Now notice, huh? If each name in the definition is common to the thing being defined, and at least one other thing, right, no name represents a completely distinct knowledge of the thing being defined, doesn't it? But each name represents a somewhat confused knowledge of the thing being defined, huh? Because no name separates it from everything else. But as you put the names together, you go from a confused knowledge of what you're defining, to a knowledge in which it is separated from everything else. And then again, you know, you can see how the natural road enters in there, right? Natural road is from the confused to the distinct, huh? And the definition takes you from the really partial, confused thoughts about the thing being defined to a, what? Altogether distinct notion of what the thing is, huh? So now we've come to the point where we want to talk about name said of what? Many things. Is your name common to many things, huh? What you're saying is, is that always true in terms like rational? Or would you say what being composed? You see, it's kind of common to give us an example of a definition of logic. The definition of man is rational animal, right? But it's not really a good example in this sense that it doesn't exemplify what you're going to find in almost all definitions, huh? That no name, it really fits just the one thing, right? Of course, rational is actually taken from a property of man, and that's how you get something convertible with man. We'll talk about property later on. But if you go back to porphyry, right, you always give, as an example of a definition of man, something like a rational mortal animal, right? And of course, with the opinion of the Platonists, right, that there were immortal, rational animals, right? But then, no part of the definition belongs only to man, right? So the fact that they take rational animal as an example there in logic books is kind of a sign of their misunderstanding or ignorance, really, of logic, right? And when porphyry defines a difference when we do it here, it's still something common to what? Many things other in kind, huh? So, we're down now to the need to talk about name common to many things or name set of many things. Now, Albert the Great, in his logical works, he says, the first thing we need to talk about in logic is the universal. But this is more sensible, meaning more most of the senses, right? To say the first thing we really have to talk about in logic is name set of, what? Many things, huh? Name common to many things, huh? And even the name of the thing being defined, huh? Is common to many things. You don't define Socrates, you define man. You don't define Lassie, you define dog, right? You don't define champions, you're not the source, but horse, right? So even the name of the thing being defined is a name set of, what? Many things. And even more so, the name set inside the definition. So now we have to talk about name set of many things, right? Now, the fundamental distinction of name set of many things is the, we use a lack of words here, name set of many things with, yeah, you want to take a little break? He'll tell us exactly when you need this because it might take most of you. Oh. Okay. The fundamental distinction now of name set of many things is whether you have one meaning in mind, right? Whether you have the same meaning in mind when you say this one word of many things, right? Or whether you have what? Many meanings in mind, right? Okay. I want to pause now. Pause now. Okay. Hard for that. Hard for that. Go back. Okay. Now notice, most names probably have many meanings. And, but even if a name has many meanings, you can say it of many things with one meaning in mind. Take the word back, for example. the word back is equivocal in the sense that it has many meanings, right? And, it could mean the piece of wood used in baseball, right? Or it could mean the flying mouse that's in the belfry, right? Okay. And if it were said of those two, it would be said of them equivocally, right? Because you wouldn't be calling this piece of wood a bat for the same reason you call this a bat. flying mouse a bat, right? You don't have the same thought in mind, the same meaning in mind. But if you said the word bat just to, let's say, three baseball bats, then that word would be said, what? Univically, right? Or with one meaning, huh? And we use the Latin word univical, or univically, the adverb, for, with one meaning, right? So we can say that a name said univically of many things is a name said with one meaning in mind of many things, right? But you have the same meaning, or the same reason, you might say, right? For calling each of these the same, right? So the word man is said of each of us, right? Is being said univically, right? Each of us is being called a man because we're a animal with reason, right? Okay? Likewise, if animal is being said of man and of dog, it's being said univically because you have the same meaning in mind, it's a living body with sensation, huh? Okay? If quadrilateral was sort of square and oblong and rhombus and rhomboid, it's said univically because you have the same meaning in mind, it's a plane figure, a rectilineal plane figure contained by four straight lines, huh? Okay? Now maybe, it's not in this text here, but maybe sometime we can talk about equivocal names, huh? Okay? Let's maybe make a little footnote here, a little petition here. Name equivocal. By chance, and name equivocal by reason. That word bat, instead of the baseball bat and the flying mouse, it's by chance that they both are called a, what, bat, huh? Some of them look at the baseball bat and the flying mouse, the feeder mouse, and say, I see that they have something in common, or I see a certain connection between these two, right? But now, sometimes a name is said of many things, equivocally, by, what, reason, huh? There's reasons why they have the same name, right? So if I say, for example, I see you, right? And I say, now, I can see my son now, I can picture my son in my imagination. Is that by chance that I call both of those seeing? Here I can see a certain likeness of my, picturing my son, right, to my see, right? When I dream, my imagining, I think, is what seeing, and the see by the likeness of the sun. So there's a reason why they're both called seeing, right? And so, we speak of such a name as being equivocal by reason, opposed to some that are equivocal by chance. Now, these words that are equivocal by reason are very important in philosophy, and especially they're important in wisdom. In fact, all the key words in wisdom are equivocal by reason. But you could say the words in the axioms are all equivocal by reason. There are scholars who discovered that the most common words are all equivocal by reason. And these are the words used also in the axioms, and these are the words that are used especially in wisdom. In fact, it's one of the 14 books of wisdom there, 14 books of metaphysics, is devoted to distinguishing the meanings of the key words in wisdom and in the axioms and everywhere, right? The words are equivocal by reason. And we had a couple examples here earlier. We talked about the word to see and to do this now again, right? But we had a little text of Aristotle where he talked about the word before, right? And the word before is a word that's equivocal by reason. And as you know, reason looks before and after. There's an order among those four meanings of the word before. Before and time or the discourse of reason that's embedded. So, in a word that's equivocal by chance, there's no order among the meanings. But in a word there's equivocal by reason that there may be a certain order and conviction among the meanings. So some people say that logic is not philosophy in the same sense that geometry or natural philosophy are philosophy. But it's a tool for acquiring geometry. You can see Euclid is starting with definitions and statements and then he adds syllogisms, right? So it's not purely by chance, it's not purely equivocal or by chance that we call logic philosophy. And it's not philosophy in the same sense as geometry, natural philosophy and wisdom. It's a tool for acquiring logic, I mean, geometry, natural philosophy and wisdom. So there's a connection between the two, right? But that word convertible, right, that seems to be almost purely equivocal there. It's an audible feel, right? Okay, now we can come back sometime and talk more about name equivocal by reason that takes place. This is the fundamental distinction between equivocal by chance and by reason. Now sometimes the name equivocal by reason they'll want to call an element, right? And sometimes the one that's equivocal by chance is just equivocal or purely. I think it's better to call them by chance and by reason to, you know, if you're talking about them. In analogous there, that's taken from one kind of name equivocal by reason so you tend to get to narrow an understanding of all the various ways that names are equivocal by reason. The most common mistake in thinking Aristotle says in the book called The Consist Repetitions is from mixing up the senses of a word. And you do so mainly with the ones that are equivocal by reason because if the meaning is ever said in similarity or close connection and you mix them up, what's an idea in English? What's an idea? If you read John Locke, he's always talking about ideas. Oh? Yeah? But sometimes an idea is a what? Image, yeah. Yeah. So, if the girl says the guy don't get ideas, she probably is using ideas in the sense of what? Image, right? Yeah. Okay? He's not doing too much thinking now, right? Right. But he's imagining it. But when we say the philosopher's ideas, it should be thoughts and not just images. So Locke is often confusing idea in the sense of image with idea in the sense of what? Thought, right? That's probably equivocal by reason, huh? And that's why Thomas spoke of how the Eric philosophers actually referenced that. They speak of the first act of reason as kind of an imagination through the understanding, right? Okay? There's sort of likeness there, right? When I imagine something, I form an image of it. When I think about something, I form a thought. Image and a thought are not the same thing. If you study John Locke, you'll see that he really confuses it too much. Okay. You can find something and you want to first know what meaning you have in mind, like down to one name, right? So, what we're going to talk about next is name said unificantly as many things, right? Okay? And the first book, really, that in the Greek philosophical edition that's come down to us as a part of logic then was a book written by Porphyry, right? And Porphyry was one of the Neopatonic philosophers, later Patonic philosophers. These are R's there, and R's too. Porphyry wrote a isogogae, which is a Greek word meaning the direction, he wrote an isogogae, Introduction to Aristotle's Categories, that Thomas referred to. The only book that's put down to us from Aristotle for the logic of the first act is this book called The Categories, which is what it's about. But Porphyry wrote this for a student who was having a hard time understanding the categories of Aristotle, right? So Porphyry wrote a book which was called The Introduction to the Categories. And what he actually does in that book is to distinguish which the name said you didn't give me anything. But as he says in the gramium, too, his isogogae, you usually see it as an English form, isogogae. He'll point out that the isogogae is useful not only for understanding the categories, but for definition, he says, and for division, and for demonstration, which is the most perfect kind of insult. And so we'll see that when we go through this on how it's useful. But it's especially, at this point, we're interested in the new definition. Now, Porphyry divides these names said you didn't give me things eventually into five, but we can arrive at those five by three divisions. Either the name which is said of many things signifies something like inside their nature, right? Meaning by nature, not what they are. Or it signifies something outside their nature. So names said you didn't give me things signifying something inside their nature. Meaning by nature, what they are. Or it signifies something out. So if you had three triangles, and you said triangle of them, or you said, or generally plain figure of them, or figure, you'd be saying something that signifies something inside their nature. But if you said green of the three triangles, you'd be signifying something what? Outside their nature. Outside of what they are. This division is obviously exhausting, right? Either it signifies something inside the nature, or many of which we said, or it signifies something outside of nature. There is no other alternative, right? Not either, right? Now he's going to subdivide, and we're going to subdivide both of these. And the first here, we're going to subdivide into three, and the second, we're going to subdivide into, what? Two. Wait, two or three. Now the first word that, or first name that he talks about is called in the Greek, the genus. In Latin you have almost the same word genus, right? And in English we take over the word genus from the Latin, right? Now the genus, the name said of many things. and we take over the word genus from the Greek, and we take over the word genus from the Greek, and we take over the word genus from the Greek, of many things, other in kind. It's a name signifying what it is. I ask in class, what is a dog? Students will usually answer, it's an animal, right? Now, animal there is an example of a genus, right? It's a name said with one meaning of many things, other in kind, like dog, cat, horse, dolphin, right? It signifies what it is, right? It signifies it in a very general way, say in English, right? Or in general, in such a logical way, it's a genus, right? Okay? Again, why do we tend to start with the genus? Whereas the genus represents a confused understanding of what the thing is, right? Confused because it's understanding what it is in common with many other things, and therefore it's not distinguishing one of those kinds from another, isn't it? I ask students, what is a sonnet? And they'll say it's a poem, right? But the sonnet is only one kind of poem or many other kinds of poems, except the sonnet, huh? If I ask somebody, what is a tragedy or a comedy, what are they going to say? Yeah, it's a play or a drama, right? But play or drama, as an example, again, would be a genus, right? When I say reason is an ability, right? The only ability, there are many different kinds of abilities that man has, right? And reason may be a very important one, but it's still, you know, one of many abilities we have. It's a name said with one meaning of many things, other in kind, signifying what it is, huh? I think I'm giving myself room here, I think I'm going to release this temporarily. Now, the second name we talk about is the name of one of these particular things that are in the genus, right? Okay? Now, the Greek word they use for that is ados, right? And the Latin word they use is, what, species, huh? And both ados in Greek and species in Latin, they have the sense of a form, but of a form you can, what, see. Ados is related to the Greek word adenai, meaning to see, right? And species is related to the word speculadivus, speculation, specular, to look, right? So it's the form or shape you see, huh? In English, we tend to borrow either the Latin word species, right? Or sometimes we simply use the word, what, form in English, right? Okay? So species is the one we use in logic. So species is the name of a particular kind of thing under a genus. So if the genus is animal, then cat and dog and horse and elephant would be, what, species, right? Species is one of those funny words that is spelled the same way, I guess, in the singular and the plural. If the genus is, what, government, right? Then maybe monarchy and oligarchy and democracy and so on would be different species of, what, government, right then? In English, you might speak of them as three forms of government, right? If play or drama is the genus, maybe tragedy and comedy species, right? Maybe there's another species in between, tragedy and comedy. If quadrilateral is the genus, square and oblong and rhombus and rhomboid, right? Square and rhomboid are the species under that genus, right? The names of the species on the forms of quadrilateral. As long as we don't have a name, like square, but you could say, in that case, use a speech and place a name. You might say that equilateral triangle and isosceles triangle and scalene triangle are the species of what? Triangle, right? We don't have a name for an equilateral triangle. Virtue and vice are names of species under the genus, what? Habit would happen in bad habits. Now, very often, you find that two is not enough, right? Like Aristotle points this out in the first book of natural philosophy. Our language is a sign of that, huh? Three is the first number about which we say all. Now, if you think about these two names, can you see the need for a third name? That's right, because the species is more particular than a genus, but doesn't say... The genus doesn't tell you distinctly what the species is, right? So if I ask you, what is democracy? And you see, what's a form of government, right? Well, so is, you know, oligarchy. So is monarchy, right? Actually, what is, you know, the tragedy you see was a play, right? Or a drama. So is comedy, right? So there's something in the species in addition to the, what, genus, right? And you need a name to bring out what the species has in addition to the, what, genus, right? Okay? Well, since these species are things other in kind, you need a name that would signify signify what distinguishes one from the other, what separates one from the other, right? And so this is the third name, which is appropriately called difference. Sometimes they call it more explicitly species-making difference, right? Okay? But usually we just call it for short the difference, species-making difference. Now, Porphyry gives, when he gets to the species-making difference, he gives actually three, in a way, definitions of difference, right? But two of them are in terms of the role of difference, right? The role of difference in defining a species and the role of difference in separating one species from another. So as you can see in the text there, you'll say the difference is the name of what the species has in addition to the genus, right? Okay? Or the species is the name of what separates one species from another. Species under the same genus. But those two definitions are of difference in terms of its function in defining something, right? And its function or use in dividing a genus into species, separating species. So, but if you stop and think about it, it's going to be the same name that separates one species from another that is also used to define a species, huh? Now, take again a simple example there. Take the genus quadrilateral, right, huh? Well, equilateral, say, or right-angled, huh? These are names of what some of the species of quadrilateral have in addition to being four-sided, right? Some of them, in addition to being four-sided, have those four sides, what, equal, right? Some don't, right? Okay. Some of them, in addition to being four-sided, they have those sides being at right angles, and some do not, right? So right-angled is both the name of something that, let's say, the square and the oblong have in addition to being quadrilateral. But right-angled also separates square and oblong from rhombus and rhomboid and even trepezium, huh? Likewise, equilateral, right, are something that square and rhombus have in common, right? The rhombus is like a square that's being jerk, right? So it's not a right-angled, but it's still equilateral. They're to the square. And why the rhomboid is what, like an oblong that's been like jerk, right? The way I remember that mnemonically is the rhombus pins an S. The S is the third, but it's square. So the rhombus is like a square, isn't it? Yeah, that's how I remember. But the rhombus equilateral separates the square and the rhombus, then, from the oblong and the rhomboid, and from the pinsing, too, see? Okay. So the same name that is a name of what the square and the rhombus have in common, or in addition to equilateral, right? It's also a name that separates the square and the rhombus from the other, like, yeah, the other one, the species of quadrilateral, right? So he looks at both the use of the difference in defining, right? Because in order to complete the definition of square, you've got to add to the genus, but square has an addition to being quadrilateral, right? And that's both equilateral and right-angled, right? But he also speaks of its use in dividing a genus into species, and actually the word difference is using the Latin word, right? The Greek word is etymologically the same. The Greek word is dia-phora, but they come from ferro or forak, which means to carry, and dia, which means apart. So when you say quadrilateral, these things seem to be, what, together, right? And in the difference, what, carries them apart, and separates them, right? Equilateral separates square and rhombus from debithee, right? And then, you know, right-angled separates, you know, oblong and square from the rest, right? And the combination, as we saw, of like pre-lateral and right-angled separates the square from all the rest, right? Okay? So it's, in fact, the same name that separates species under the same genus, right? And that is also the name of what those species have in addition to the genus, right? So it's both the name that's going to be used to complete the definition, right? And the name that's going to be used to divide a genus into its species. You can see that you can write the definition of things like square, right? But also to divide quadrilateral into the various things of quadrilateral. But then, Torfrey gives a definition of difference going back to what we're dividing, right? And he says that it's a name said with one meaning of many things other in kind that signify, instead of what it is, signify how they are what they are. It's important to see that it signifies how rather than what, right? But you have to add, it signifies how they are what they are because it's an essential difference in the very nature of the things, as opposed to just a how by itself. It might be something accidental, like how are you today? Or I'm well today, or I'm sick today, or something like that, right? But this is how they are what they are. So it's the same definition as genus, except for the last part. Instead of signifying what it is, it signifies how. Wow, that's the difference now, this definition of difference. Now, Porphy is not yet here, and following you, we have not yet given a definition of species as a name said to live in many things, right? And we'll see the reason for that later on when we discuss how the same thing can be the same species. It's really only what they call the lowest species, but that's another thing before we see that. So you have the definition there of difference and of genus as names said identically of many things, right? Signifying something in the nature, but the one signifies in a general way what they are, and the other signifies how they are. Now, as we go on here, right, you can see how those three names are very important to talk about definition, because the species is the name of what is being defined, and the genus and the differences are names, right, used to define. But the first and most basic name is the genus, right? Then you have to add usually two or more differences, right, to complete the definition. So we've separated here, right, the name of the thing being defined, which is called the species. You're always defining a species, a particular kind of thing, right? And the name that begins the definition and the name that completes the definition. This is what we've said before. Now we have to define what a name is, right? We have to distinguish between the name of the thing being defined and the names used in the definition, right? And even among the names used in the definition between the, what, genus and the difference and the order among them, that the genus is meaning the fundamental name, right? And the differences determine how it is what it is, right? Any question about that? Now, since the other names said you didn't give any thing signify something outside the nature, right? Outside what the thing is. It might seem superfluous to subdivide those names, right? Because the definition is to say what the thing is, right? But there is a reason for subdividing those other names. Even as we bear its definition, but also as we bear its later on demonstration. And you'll see that once we've septified those names. Praise that.