METAPHYSICS
BOOK IVTHE SUBJECT OF METAPHYSICS, DEMONSTRATIVELY
CONTENTS
LESSON 1
The Proper Subject Matter of This Science: Being as Being, and Substance and Accidents
ARISTOTLE’S TEXT Chapters 1 & 2: 1003a-1003b 22
294. There is a certain science which studies being as being and the attributes which necessarily belong to being.
295. This science is not the same as any of the so-called particular sciences; for none of the other sciences attempt to study being as being in general, but cutting off some part of it they study the accidents of this part. This, for example, is what the mathematical sciences do.
296. Now since we are seeking the principles and ultimate causes of things, it is evident that these must be of themselves the causes of some nature. Hence, if those who sought the elements of beings sought these principles, they must be the elements of beings not in any accidental way but inasmuch as they are beings. Therefore the first causes of being as being must also be understood by us.
Chapter 2
297. The term being is used in many senses, but with reference to one thing and to some one nature and not equivocally. Thus everything healthy is related to health, one thing because it preserves health, another because it causes it, another because it is a sign of it (as urine) and still another because it is receptive of it. The term medical is related in a similar way to the art of medicine; for one thing is called medical because it possesses the art of medicine, another because it is receptive of it, and still another because it is the act of those who have the art of medicine. We can take other words which are used in a way similar to these. And similarly there are many senses in which the term being is used, but each is referred to a first principle. For some things are called beings because they are substances; others because they are affections of substances; others because they are a process toward substance, or corruptions or privations or qualities of substance, or because they are productive or generative principles of substance, or of things which are related to substance, or the negation of some of these or of substance. For this reason too we say that non-being is non-being.
298. Therefore, just as there is one science of all healthy things, so too the same thing is true in other cases. For it is the office of one and the same science to study not only those things which are referred to one thing but also those which are referred to one nature. For those too in a sense are referred to one thing.
299. It is evident, then, that it is the function of one science to study beings as beings.
299a. But in every respect a science is concerned with what is primary, and that on which other things depend, and form which they derive their name. Hence, if this is substance, it must be of substances that the philosopher possesses the principles and causes.
300. Now of every single class of things there is one sense and one science; for example, grammar, which is one science, studies all words. And for this reason too it belongs to a general science to study all species of being as being and the species of these species.
COMMENTARY
It is being and its properties
529. In the preceding book the Philosopher proceeded to treat dialectically the things which ought to be considered in this science. Here he begins to proceed demonstratively by establishing the true answer to those questions which have been raised and argued dialectically.
In the preceding book he treated dialectically both the things which pertain to the method of this science, namely, those to which the consideration of this science extends, as well as those which fall under the consideration of this science. And because it is first necessary to know the method of a science before proceeding to consider the things with which it deals, as was explained in Book II (335), this. part is therefore divided into two members. First, he speaks of the things which this science considers; and second (749), of those which fall under its consideration. He does this in Book V (“In one sense the term principle”).
The first part is divided into two members. First, he establishes what the subject matter of this science is. Second (534), he proceeds to answer the questions raised in the preceding book about the things which this science considers (“The term being”).
In regard to the first he does three things. First, he submits that there is a science whose subject is being. Second (532), he shows that it is not one of the particular sciences (“But this science”); and third (533), he shows that it is the science with which we are now dealing (“Now since”).
Now because a science should investigate not only its subject but also the proper accidents of its subject, he therefore says, first, that there is a science which studies being as being, as its subject, and studies also “the attributes which necessarily belong to being,” i.e., its proper accidents.
530. He says “as being” because the other sciences, which deal with particular beings, do indeed consider being (for all the subjects of the sciences are beings), yet they do not consider being as being, but as some particular kind of being, for example, number or line or fire or the like.
531. He also says “and the attributes which necessarily belong to being,” and not just those which belong to being, in order to show that it is not the business of this science to consider those attributes which belong accidentally to its subject, but only those which belong necessarily to it. For geometry does not consider whether a triangle is of bronze or of wood, but only considers it in an absolute sense according as it has three angles equal to two right angles. Hence a science of this kind, whose subject is being, must not consider all the attributes which belong accidentally to being, because then it would consider the accidents investigated by all sciences; for all accidents belong to some being, but not inasmuch as it is being. For those accidents which are the proper accidents of an inferior thing are related in an accidental way to a superior thing; for example, the proper accidents of man are not the proper accidents of animal.
Now the necessity of this science, which considers being and its proper accidents, is evident from this, that such things should not remain unknown since the knowledge of other things depends on them, just as the knowledge of proper objects depends on that of common objects.
532. This science (295).
Then he shows that this science is not one of the particular sciences, and he uses the following argument. No particular science considers universal being as such, but only some part of it separated. from the others; and about this part it studies the proper accidents. For example, the mathematical sciences study one kind of being, quantitative being. But the common science considers universal being as being, and therefore it is not the same as any of the particular sciences.
533. Now since (296).
Here he shows that the science with which we are dealing has being as its subject, and he uses the following argument. Every principle is of itself the principle and cause of some nature. But we are seeking the first principles and ultimate causes of things, as was explained in Book I (57), and therefore these are of themselves the causes of some nature. But this nature can only be the nature of being. This is clear from the fact that all philosophers, in seeking the elements of things inasmuch as they are beings, sought principles of this kind, namely, the first and ultimate ones. Therefore in this science we are seeking the principles of being as being. Hence being is the subject of this science, for any science seeks the proper causes of its subject.
It applies analogically to the different categories.
534. The term “being” (297).
Then he proceeds to answer the questions raised in the preceding book about the things which this science considers, and this is divided into three parts. First, he answers the question whether this science considers substances and accidents together, and whether it considers all substances. Second (548), he answers the question whether it belongs to this science to consider all of the following: one and many, same and different, opposites, contraries, and so forth (“Now although”). Third (588), he answers the question whether it belongs to this science to consider the principles of demonstration (“Moreover, it is necessary”).In regard to the first he does three things. First, he shows that it is the office of this science to consider both substances and accidents. Second (546), he shows that this science is chiefly concerned with substances (“But in every respect”). Third (547), he shows that it pertains to this science to consider all substances (“Now of every”).
In regard to the first part he uses this kind of argument: those things which have one term predicated of them in common, not univocally but analogously, belong to the consideration of one science. But the term being is thus predicated of all beings. Therefore all beings, i.e., both substances and accidents, belong to the consideration of one science which considers being as being.
535. Now in this argument he gives, first (535), the minor premise; second (544), the major premise (“Therefore, just as”); and third (545), the conclusion (“It is evident, then”).
He accordingly says, first, that the term being, or what is, has several meanings. But it must be noted that a term is predicated of different things in various senses. Sometimes it is predicated of them according to a meaning which is entirely the same, and then it is said to be predicated of them univocally, as animal is predicated of a horse and of an ox. Sometimes it is predicated of them according to meanings which are entirely different, and then it is said to be predicated of them equivocally, as dog is predicated of a star and of an animal. And sometimes it is predicated of them according to meanings which are partly different and partly not (different inasmuch as they imply different relationships, and the same inasmuch as these different relationships are referred to one and the same thing), and then it is said “to be predicated analogously,” i.e., proportionally, according as each one by its own relationship is referred to that one same thing.
536. It must also be noted that the one thing to which the different relationships are referred in the case of analogical things is numerically one and not just one in meaning, which is the kind of oneness designated by a univocal term. Hence he says that, although the term being has several senses, still it is not predicated equivocally but in reference to one thing; not to one thing which is one merely in meaning, but to one which is one as a single definite nature. This is evident in the examples given in the text.
537. First, he gives the example of many things being related to one thing as an end. This is clear in the case of the term healthy or healthful. For the term healthy is not predicated univocally of food, medicine, urine and an animal; because the concept healthy as applied to food means something that preserves health; and as applied to medicine it means something that causes health; and as applied to urine it means something that is a sign of health; and as applied to an animal it means something that is the recipient or subject of health. Hence every use of the term healthy refers to one and the same health; for it is the same health which the animal receives, which urine is a sign of, which medicine causes, and which food preserves.
538. Second, he gives the example of many things being related to one thing as an efficient principle. For one thing is called medical because it possesses the art of medicine, as the skilled physician. Another is called medical because it is naturally disposed to have the art of medicine, as men who are so disposed that they may acquire the art of medicine easily (and according to this some men can engage in medical activities as a result of a peculiar natural constitution). And another is called medical or medicinal because it is necessary for healing, as the instruments which physicians use can be called medical. The same thing is also true of the things called medicines, which physicians use in restoring health. Other terms which resemble these in having many senses can be taken in a similar way.
539. And just as the above-mentioned terms have many senses, so also does the term being. Yet every being is called such in relation to one first thing, and this first thing is not an end or an efficient cause, as is the case in the foregoing examples, but a subject.
For some things are called beings, or are said to be, because they have being of themselves, as substances, which are called beings in the primary and proper sense. Others are called beings because they are affections or properties of substances, as the proper accidents of any substance. Others are called beings because they are processes toward substance, as generation and motion. And others are called beings because they are corruptions of substances; for corruption is the process toward non-being just as generation is the process toward substance. And since corruption terminates in privation just as generation terminates in form, the very privations of substantial forms are fittingly called beings. Again, certain qualities or certain accidents are called beings because they are productive or generative principles of substances or of those things which are related to substance according to one of the foregoing relationships or any other relationship.
And similarly the negations of those things which are related to substances, or even substance itself, are also called beings. Hence we say that non-being is non-being. But this would not be possible unless a negation possessed being in some way.
540. But it must be noted that the above-mentioned modes of being can be reduced to four.
(1) For one of them, which is the most imperfect, i.e., negation and privation, exists only in the mind. We say that these exist in the mind because the mind busies itself with them as kinds of being while it affirms or denies something about them. In what respect negation and privation differ will be treated below (564).
541. (2) There is another mode of being inasmuch as generation and corruption are called beings, and this mode by reason of its imperfection comes close to the one given above. For generation and corruption have some admixture of privation and negation, because motion is an imperfect kind of actuality, as is stated in the Physics, Book III.
542. (3) The third mode of being admits of no admixture of non-being, yet it is still an imperfect kind of being, because it does not exist of itself but in something else, for example, qualities and quantities and the properties of substances.
543. (4) The fourth mode of being is the one which is most perfect, namely, what has being in reality without any admixture of privation, and has firm and solid being inasmuch as it exists of itself. This is the mode of being which substances have. Now all the others are reduced to this as the primary and principal mode of being; for qualities and quantities are said to be inasmuch as they exist in substances; and motions and generations are said to be inasmuch as they are processes tending toward substance or toward some of the foregoing; and negations and privations are said to be inasmuch as they remove some part of the preceding three.
544. Therefore, just as (298).
Here he gives the major premise of the first argument. He says that it is the office of one science to study not only those things which are referred “to one thing,” i.e., to one common notion, but also those which are referred to one nature according to different relationships. And the reason for this is that the thing to which they are referred is one; just as it is clear that one science, medicine, considers all health-giving things. The same thing holds true of other things which are spoken of in the same way.
545. It is evident (299).
Then he draws his intended conclusion. This is evident of itself.
546. But in every (299a).
Then he shows that this science, even though it considers all beings, is chiefly concerned with substances. He uses the following argument. Every science which deals with many things that are referred to one primary thing is properly and principally concerned with that primary thing on which other things depend for their being and from which they derive their name; and this is true in every case. But substance is the primary kind of being. Hence the philosopher who considers all beings ought to consider primarily and chiefly the principles and causes of substances. Therefore his consideration extends primarily and chiefly to substances.
547. Now of every (300).
Then he shows by the following argument that it is the business of the first philosopher to consider all substances. There is one sense and one science of all things belonging to one class; for example, sight is concerned with all colors, and grammar with all words. Therefore, if all beings somehow belong to one class, all species of being must belong to the consideration of one science which is a general science, and different species of being must belong to the different species of that science. He says this because it is not necessary for one science to consider all the species of one genus according to the special notes of every single species, but only inasmuch as they agree generically. But according to their specific notes the different species of one genus belong to the special sciences, as happens in the present case. For inasmuch as all substances are beings or substances, they belong to the consideration of this science; but inasmuch as they are a particular kind of substance, as a lion or an ox, they belong to the special sciences.
LESSON 2
This Science Considers Being and Unity. The Parts of Philosophy Based on the Divisions of Being and Unity
ARISTOTLE’S TEXT Chapter 2: 1003b 22-1004a 9
301. Now although being and unity are the same and are a single nature in the sense that they are associated like principle and cause, they are not the same in the sense that they are expressed by a single concept. Yet it makes no difference even if we consider them to be the same; in fact this will rather support our undertaking.
302. For one man and human being and man are the same thing; and nothing different is expressed by repeating the terms when we say, “This is a human being, a man, and one man.” And it is evident that they are not separated either in generation or in corruption. The same holds true of what is one. Hence it is evident that any addition to these expresses the same thing, and that unity is nothing else than being.
303. Further, the substance of each thing is one in no accidental way; and similarly it is something that is.
304. Hence there are as many species of being as there are of unity, of which it is the office of the same general science to treat. I mean, for example, sameness and likeness and other such attributes. And almost all contraries may be referred to this starting point. But these have been studied by us in our selection, i.e., in our explanation or treatment, of contraries.
305. And there are just as many parts of philosophy as there are substances, so that there must be a first philosophy and one which is next in order to it. For being and unity are things which straightway have genera; and for this reason the sciences will correspond to these. For the term philosopher is used like the term mathematician; for mathematics too has parts, and there is a first and a second science and then others “ following these among the mathematical sciences.
COMMENTARY
Metaphysics also treats of “being-one”.
548. Here he proceeds to show that the study of common attributes such as one and many and same and different belongs to the consideration of one and the same science; and in regard to this he does two things. First, he shows that this is true of each attribute taken separately by arguing from proper or specific principles. Second (570), he shows that this is true of all attributes taken together by arguing from common principles.
In regard to the first he does two things. First, he shows that the philosopher ought to investigate all these attributes. Second (568), he tells us how to investigate them.
In regard to the first he does two things. First, he shows that it is the office of this science to consider unity and its species. Second (564), he shows that it is the office of one and the same science to consider all opposites.
In regard to the first he does two things. First, he shows that it is the office of this science to consider unity. Second (561), he shows that it also,belongs to it to examine the species of unity.
He therefore says, first, that being and unity are the same and are a single nature. He says this because some things are numerically the same which are not a single nature but different natures, for example, Socrates, this white thing, and this musician. Now the terms one and being do not signify different natures but a single nature. But things can be one in two ways: (1) for some things are one which are associated as interchangeable things, like principle and cause; and (2) some are interchangeable not only in the sense that they are one and the same numerically [or in subject] but also in the sense that they are one and the same conceptually, like garment and clothing.
549. Now the terms one and being signify one nature according to different concepts, and therefore they are like the terms principle and cause, and not like the terms tunic and garment, which are wholly synonymous. —Yet it makes no difference to his thesis if we consider them to be used in the same sense, as those things which are one both numerically and conceptually. In fact this will “rather support our undertaking,” i.e., it will serve his purpose better; for he intends to prove that unity and being belong to the same study, and that the species of the one correspond to those of the other. The proof of this would be clearer if unity and being were the same both numerically and conceptually rather than just numerically and not conceptually.
550. He proves that they are the same numerically by using two arguments. He gives the first where he says, “For one man,” and it runs as follows. Any two things which when added to some third thing cause no difference are wholly the same. But when one and being are added to man or to anything at all, they cause no difference. Therefore they are wholly the same. The truth of the minor premise is evident; for it is the same thing to say “man” and “one man.” And similarly it is the same thing to say “human being” and “the thing that is man;” and nothing different is expressed when in speaking we repeat the terms, saying, “This is a human being, a man, and one man.” He proves this as follows.
551. It is the same thing for man and the thing that is man to be generated and corrupted. This is evident from the fact that generation is a process toward being, and corruption a change from being to non-being. Hence a man is never generated without a human being being generated, nor is a man ever corrupted without a human being being corrupted; and those things which are generated and corrupted together are themselves one and the same.
552. And just as it has been said that being and man are not separated either in generation or in corruption, so too this is evident of what is one; for when a man is generated, one man is generated, and when a man is corrupted, one man is also corrupted. It is clear, then, that the apposition of these [i.e., of one or being to man] expresses the same thing, and that just because the term one or being is added to man it is not to be understood that some nature is added to man. And from this it is clearly apparent that unity does not differ from being, because any two things which are identical with some third thing are identical with each other.
553. It is also evident from the foregoing argument that unity and being are the same numerically but differ conceptually; for if this were not the case they would be wholly synonymous, and then it would be nonsense to say, “a human being,” and “one man.” For it must be borne in mind that the term man is derived from the quiddity or the nature of man, and the term thing from the quiddity only; but the term being is derived from the act of being, and the term one from order or lack of division; for what is one is an undivided being. Now what has an essence, and a quiddity by reason of that essence, and what is undivided in itself, are the same. Hence these three—thing, being, and one—signify absolutely the same thing but according to different concepts.
554. Further, the substance (303).
Then he gives the second argument, which has to do with sameness or identity of subject. This argument is as follows. Any two attributes which are predicated essentially and not accidentally of the substance of each thing are the same in subject, or numerically. But unity and being are such that they are predicated essentially and not accidentally of the substance of each thing; for the substance of a thing is one in itself and not accidentally. Therefore the terms being and one signify the same thing in subject.
555. That the terms being and one are predicated essentially and not accidentally of the substance of each thing can be proved as follows. If being and one were predicated of the substance of each thing by reason of something added to it [i.e., accidentally], being would have to be predicated also of the thing added, because anything at all is one and a being. But then there would be the question whether being is predicated of this thing (the one added) either essentially or by reason of some other thing that is added to it in turn. And if the latter were the case, then the same question would arise once again regarding the last thing added, and so on to infinity. But this is impossible. Hence the first position must be held, namely, that a thing’s substance is one and a being of itself and not by reason of something added to it.
556. But it must be noted that Avicenna felt differently about this; for he said that the terms being and one do not signify a thing’s substance but something added to it. He said this of being because, in the case of anything that derives its existence from something else, the existence of such a thing must differ from its substance or essence. But the term being signifies existence itself. Hence it seems that being, or existence is something added to a thing’s essence.
557. He spoke in the same way of one, because he thought that the one which is interchangeable with being and the one which is the principle of number are the same. And the one which is the principle of number must signify a reality added to the substance, otherwise number, since it is composed of ones, would not be a species of quantity, which is an accident added to substance. He said that this kind of one is interchangeable with being, not in the sense that it signifies the very substance of a thing or being, but in the sense that it signifies an accident belonging to every being, just as the ability to laugh belongs to every man.
558. But in regard to the first point he does not seem to be right; for even though a thing’s existence is (+) other than its essence, it should not be understood to be something added to its essence after the manner of an (~) accident, but (+) something established, as it were, by the principles of the essence. Hence the term being, which is applied to a thing by reason of its very existence, designates the same thing as the term which is applied to it by reason of its essence. [Existence is later clarified as the act of essence.]
559. Nor does it seem to be true that the one or unity which is interchangeable with being and that which is the principle of number are the same; for nothing that pertains to some special class of being seems to be characteristic of all beings. Hence the unity which is limited to a special class of being—discrete quantity—does not seem to be interchangeable with universal being. For, if unity is a proper and essential accident of being, it must be caused by the principles of being as being, just as any proper accident is caused by the principles of its subject. But it is not reasonable that something having a particular mode of being should be adequately accounted for by the common principles of being as being. It cannot be true, then, that something which belongs to a definite genus and species is an accident of every being.
560. Therefore the kind of unity which is the principle of number differs from that which is interchangeable with being; for the unity which is interchangeable with being signifies being itself, adding to it the notion of undividedness, which, since it is a negation or a privation, does not posit any reality added to being. Thus unity differs from being in no way numerically but only conceptually; for a negation or a privation is not a real being but a being of reason, as has been stated (540).
However, the kind of unity which is the principle of number adds to substance the note of a measure, which is a special property of quantity and is found first in the unit. And it is described as the privation or negation of division which pertains to continuous quantity; for number is produced by dividing the continuous. Hence number belongs to mathematical science, whose subject cannot exist apart from sensible matter but can be considered apart from sensible matter. But this would not be so if the kind of unity which is the principle of number were separate from matter in being and existed among the immaterial substances, as is true of the kind of unity which is interchangeable with being.
561. Hence there are (304).
Then he concludes that it is the business of the philosopher to consider the parts of unity, just as it is to consider the parts of being. First, he proves this; and second (563), he shows that there are different parts of philosophy corresponding to the different parts of being and unity.
He says, first, that since being and unity signify the same thing, and the species of things that are the same are themselves the same, there must be as many species of being as there are of unity, and they must correspond to each other. For just as the parts of being are substance, quantity, quality, and so on, in a similar way the parts of unity are sameness, equality and likeness. For things are the same when they are one in substance, equal when they are one in quantity, and like when they are one in quality. And the other parts of unity could be taken from the other parts of being, if they were given names. And just as it is the office of one science, philosophy, to consider all parts of being, in a similar way it is the office of this same science to consider all parts of unity, i.e., sameness, likeness and so forth. And to this “starting point,” i.e., unity, “almost” all contraries may be referred.
562. He adds this qualification because in some cases this point is not so evident. Yet it must be true; for since one member of every pair of contraries involves privation, they must be referred back to certain primary privatives, among which unity is the most basic.
And plurality, which stems from unity, is the cause of otherness, difference and contrariety, as will be stated below. He says that this has been treated “in our selection,” or extract, “of contraries,” i.e., a treatise which is the part selected to deal with contraries, namely, Book X (2000-21) of this work.
563. And there are (305).
Here he shows that the parts of philosophy are distinguished in reference to the parts of being and unity. He says that there are as many parts of philosophy as there are parts of substance, of which being and unity chiefly are predicated, and of which it is the principal intention or aim of this science to treat.
And because the parts of substance are related to each other in a certain order, for immaterial substance is naturally prior to sensible substance, then among the parts of philosophy there must be a first part. (1) Now that part which is concerned with sensible substance is first in the order of instruction, because any branch of learning must start with things which are better known to us. He treats of this part in Books VII (1300) and VIII of this work. (2) But that part which has to do with immaterial substance is prior both in dignity and in the aim of this science. This part is treated in Book XII (2488) of this work.
Yet whatever parts are first must be continuous with the others, because all parts have unity and being as their genus. Hence all parts of this science are united in the study of being and unity, although they are about different parts of substance. Thus it is one science inasmuch as the foregoing parts are things which correspond to “these,”i.e., to unity and being, as common attributes of substance. In this respect the philosopher resembles the mathematician; for mathematical science has different parts, one of which is primary, as arithmetic, another secondary, as geometry, and others following these in order, as optics, astronomy and music.
LESSON 3
The Same Science Considers Unity and Plurality and All Opposites. The Method of Treating These
ARISTOTLE’S TEXT Chapter 2: 1004a 9-1004a 34
306. Now since it is the office of a single science to study opposites, and plurality is the opposite of unity, it is also the office of a single science to study negation and privation, because in both cases we are studying the unity of which there is negation or privation. And this (negation or privation) is what is stated either absolutely because an attribute is not present in a thing or (not absolutely) because it is not present in some determinate class. Therefore this difference is present in unity over and above what is implied in negation; for negation is the absence of the thing in question. But in the case of privation there is an underlying subject of which the privation is predicated.
307. But plurality is the opposite of unity. Hence the opposites of the abovementioned concepts, otherness, unlikeness, and inequality, and any others which are referred to plurality or unity, must come within the scope of the science mentioned above. And contrariety is one of these; for contrariety is a kind of difference, and difference is a kind of otherness.
308. Hence, since the term one is used in many senses, the terms designating the foregoing opposites will also be used in many senses. Yet it is the business of one science to know them all. For even if some term is used in many senses, it does not therefore follow that it belongs to another science. Hence if terms are not used with one meaning, and their concepts are not referred to one thing, then it is the office of a different science to study them. But since all things are referred to some primary thing, as all things which are one are referred to a primary one, the same thing must hold true of sameness, otherness, and the contraries. It is necessary, then to distinguish all the senses in which each term is used and then refer them back to the primary thing signified in each of the predicates in question to see how each is related to it. For one thing is given a particular predicate because it possesses it, another because it produces it, and others in other ways.
309. Hence it is evident, as has been stated in our problems, that it is the office of a single science to give an account of these predicates as well as of substance; and this was one of the problems (181:C 346; 202:C 393).
COMMENTARY
It also considers “one-many”, “negation-privation” etc.
564. Here he shows that it is the office of this science to consider opposites; and in regard to this he does two things. First, he shows that it is the office of this science to consider privation and negation; and second (567), to consider contraries (“But plurality”).
He accordingly says (306) that, since it pertains to one science to consider opposites (for example, it belongs to medicine to consider health and sickness, and to grammar to consider agreement and disagreement), and since plurality is the opposite of unity, the study of privation and negation must belong to that science which deals with unity and plurality. For the consideration “of both” involves unity; that is, the study of unity, whose concept entails negation and privation, depends on both of these. For, as has been said above (553), what is one is an undivided being, and division relates to plurality, which is the opposite of unity. Hence the study of negation and privation belongs to that science whose business it is to consider unity.
565. Now there are two kinds of negation: (1) simple negation, by which one thing is said absolutely not to be present in something else, and (2) negation in a genus, by which something is denied of something else, not absolutely, but within the limits of some determinate genus. For example, not everything that does not have sight is said absolutely to be blind, but something within the genus of an animal which is naturally fitted to have sight.
And this difference is present in unity over and above “what is implied in negation”; i.e., it is something by which it differs from negation, because negation expresses only the absence of something, namely, what it removes, without stating a determinate subject. (1) Hence simple negation can be verified both of a non-being, which is not naturally fitted to have something affirmed of it, and of a being which is naturally fitted to have something affirmed of it and does not. For unseeing can be predicated both of a chimera and of a stone and of a man. (2) But in the case of privation there is a determinate nature or substance of which the privation is predicated; for not everything that does not have sight can be said to be blind, but only that which is naturally fitted to have sight. Thus since the negation which is included in the concept of unity is a negation in a subject (otherwise a non-being could be called one), it is evident that unity differs from simple negation and rather resembles the nature of privation, as is stated below in Book X (2069) of this work.
566. But it must be noted that, although unity includes an implied privation, it must not be said to include (~) the privation of plurality; for, since a privation is subsequent in nature to the thing of which it is the privation, it would follow that unity would be subsequent in nature to plurality. And it would also follow that plurality would be given in the definition of unity; for a privation can be defined only by its opposite. For example, if someone were to ask what blindness is, we would answer that it is the privation of sight. Hence, since unity is given in the definition of plurality (for plurality is an aggregate of units), it would follow that there would be circularity in definitions. (+) Hence it must be said that unity includes the privation of division, although not (~) the kind of division that belongs to quantity; for this kind of division is limited to one particular class of being and cannot be included in the definition of unity. (+) But the unity which is interchangeable with being implies the privation of formal division, which comes about through opposites, and whose primary root is the opposition between affirmation and negation. For those things are divided from each other which are of such a kind that one is not the other. Therefore being itself is understood first, and then non-being, and then division, and then the kind of unity which is the privation of division, and then plurality, whose concept includes the notion of division just as the concept of unity includes the notion of undividedness. However, some of the things that have been distinguished in the foregoing way can be said to include the notion of plurality only if the notion of unity is first attributed to each of the things distinguished.
567. But plurality (307).
Here he shows that it is the business of the philosopher to consider contraries, or opposites; for plurality is the opposite of unity, as has been said (564), and it is the office of one science to consider opposites. Hence, since this science considers unity, sameness, likeness and equality, it must also consider their opposites, plurality, otherness or diversity, unlikeness and inequality, and all other attributes which are reduced to these or even to unity and plurality. And contrariety is one of these; for contrariety is a kind of difference, namely, of things differing in the same genus. But difference is a kind of otherness or diversity, as is said in Book X (2017). Therefore contrariety belongs to the consideration of this science.
568. Hence, since (308).
Then he deals with the method by which the philosopher ought to establish these things. He says that, since all of the above-mentioned opposites are derived from unity, and the term one is used in many senses, all of the terms designating these must also be used in many senses, i.e., same, other, and so on. Yet even though all of these are used in many senses, it is still the work of one science, philosophy, to know the things signified by each of these terms. For if some term is used in many senses, it does not therefore follow that it belongs to another or different science. For if the different things signified are not referred to “with one meaning,” or according to one concept, i.e., univocally, or are not referred to one thing in different ways, as in the case of analogous things, then it follows that it is the office of another, i.e., of a different, science, to consider them; or at least it is the office of one science accidentally, just as astronomy considers a star in the heavens, i.e., the dog star, and natural science considers a dog-fish and a dog. But all of these are referred to one starting point. For things signified by the term one, even though diverse, are referred back to a primary thing signified as one; and we must also speak in the same way of the terms same, other, contrary, and others of this kind.Regarding each of these terms, then, the philosopher should do two things. (1) First, he should distinguish the many senses in which each may be used; and (2) second, he should determine regarding “each of the predicates,” i.e., each of the names predicated of many things, to what primary thing it is referred. For example, he should state what the first thing signified by the term same or other is, and how all the rest are referred to it; one inasmuch as it possesses it, another inasmuch as it produces it, or in other ways of this kind.
569. Hence it is evident (309).
He draws his conclusion from what has been said, namely, that it belongs to this science to reason about those common predicates and about substance; and this was one of the problems investigated in the questions treated dialectically in Book III (393).
LESSON 4
First Philosophy Considers All Contraries. Its Distinction from Logic
ARISTOTLE’S TEXT Chapter 2: 1004a 34-1005a 18
310. And it is also evident that it is the function of the philosopher to be able to study all things. For if it is not the function of the philosopher, who is it that will investigate whether Socrates and Socrates sitting are the same person, or whether one thing has one contrary, or what a contrary is, or how many meanings it has? And the same applies to other questions of this kind. Therefore, since these same things are the essential properties of unity as unity and of being as being, but not as numbers or lines or fire, evidently it is the office of this science to know both the quiddities of these and their accidents. Therefore those who have been studying these things do not err by being unphilosophical, but because substance, to which they pay no attention, is first. Now there are properties of number as number, for example, oddness and evenness, commensurability and equality, excess and defect, and these belong to numbers either in themselves or in relation to one another. And similarly there are properties of the solid, and of what is changeable and what is unchangeable, and of what is heavy and what is light. And in a similar fashion there are properties of being as being; and these are the ones about which the philosopher has to investigate the truth.
311. An indication of this is the following. Dialecticians and sophists assume the same guise as the philosopher, for sophistry is apparent wisdom, and dialecticians dispute about all things, and being is common to all things. But evidently they dispute about these matters because they are common to philosophy. For sophistry and dialectics are concerned with the same class of things as philosophy.
312. But philosophy differs from the latter in the manner of its power, and from the former in the choice, i.e., selection, of a way of life. For dialectics is in search of knowledge of what the philosopher actually knows, and sophistry has the semblance of wisdom but is not really such.
313. Further, one corresponding member of each pair of contraries is privative, and all contraries are referred to being and to non-being and to unity and to plurality; for example, rest pertains to unity and motion to plurality.
314. And almost all men admit that substance and beings are composed of contraries; for all say that principles are contraries. For some speak of the odd and even, others of the hot and cold, others of the limited and unlimited, and others of love and hate.
315. And all the other contraries seem to be reducible to unity and plurality. Therefore let us take that reduction for granted. And all the principles which have to do with other things fall under unity and being as their genera.
316. It is clear from these discussions, then, that it is the office of one science to study being as being. For all beings are either contraries or composed of contraries, and the principles of contraries are unity and plurality. And these belong to one science, whether they are used in one sense or not. And perhaps the truth is that they are not. Yet even if the term one is used in many senses, all will be referred to one primary sense; and the same is true of contraries. Hence, even if unity or being is not a universal and the same in all things or is something separate (as presumably it is not), still in some cases the thing will be referred to unity and in others it will be referred to what follows on unity.
317. And for this reason it is not the province of geometry to examine what a contrary is, or what the perfect is, or what unity is, or what sameness or otherness is, but to assume them.
318. It is evident, then, that it is the office of one science to study both being as being and the attributes which belong to being as being. And it is evident too that the same science studies not only substances but also their accidents, both those mentioned above, and prior and subsequent, genus and species, whole and part, and others such as these.
COMMENTARY
General reasons for that (difference between metaphysics and dialectics or sophistry).
570. Here he uses arguments based on common principles to prove what the philosopher ought to consider regarding all of the foregoing attributes. First, he proves his thesis; and second (587), he introduces his intended conclusion (“It is evident”).
In regard to the first part he does two things. First, he proves his thesis; and second (586), he draws a corollary from what has been said (“And for this reason”).
He gives three arguments to prove his thesis. The second (572) begins where he says, “An indication of this”; and the third (578), at “Further, one corresponding.”
The first argument is as follows. All questions that can be raised must be answered by some science. But questions are raised about the common attributes mentioned above, for example, that raised about sameness and otherness: whether Socrates and Socrates sitting are the same; and that raised about contraries: whether one thing has one contrary, and how many meanings the term contrary has. Hence these questions must be answered by some science which considers sameness and contrariety and the other attributes mentioned above.
571. That this is the job of the philosopher and of no one else he proves thus: that science whose office is to consider being as being is the one which must consider the first properties of being. But all of the above-mentioned attributes are proper accidents of unity and being as such. For number as number has properties, such as excess, equality, commensurability, and so on, some of which belong to a number taken absolutely, as even and odd, and some to one number in relation to another, as equality. And even substance has proper attributes, “as the resistant,” or body, and others of this kind. And in a similar way being as being has certain properties, which are the common attributes mentioned above; and therefore the study of them belongs to the philosopher. Hence those dealing with philosophy have not erred in their treatment of these things “by being unphilosophical,” i.e., by considering them in a way that does not pertain to the investigations of philosophy, but because in treating them they pay no attention to substance, as though they were completely unmindful of it despite the fact that it is the first thing which the philosopher ought to consider.
572. An indication (311).
Then he gives a second argument to prove the same point. This argument employs an example and runs thus: dialecticians and sophists assume the same guise as the philosopher inasmuch as they resemble him in some respect. But the dialectician and sophist dispute about the above-mentioned attributes. Therefore the philosopher should also consider them. In support of his first premise he shows how dialectics and sophistry resemble philosophy and how they differ from it.
573. Dialectics resembles philosophy in that it is also the office of the dialectician to consider all things. But this could not be the case unless he considered all things insofar as they agree in some one respect; because each science has one subject, and each art has one matter on which it operates. Therefore, since all things agree only in being, evidently the subject matter of dialectics is being and those attributes which belong to being; and this is what the philosopher also investigates. And sophistry likewise resembles philosophy; for sophistry has “the semblance of wisdom,” or is apparent wisdom, without being wisdom. Now anything that takes on the appearance of something else must resemble it in some way. Therefore the philosopher, the dialectician and the sophist must consider the same thing.
574. Yet they differ from each other. The philosopher differs from the dialectician in power, because the consideration of the philosopher is more efficacious than that of the dialectician. For the philosopher proceeds demonstratively in dealing with the common attributes mentioned above, and thus it is proper to him to have scientific knowledge of these attributes. And he actually knows them with certitude, for certain or scientific knowledge is the effect of demonstration. The dialectician, however, proceeds to treat all of the above-mentioned common attributes from probable premises, and thus he does not acquire scientific knowledge of them but a kind of opinion. The reason for this difference is that there are two kinds of beings: beings of reason and real beings. The expression being of reason is applied properly to those notions which reason derives from the objects it considers, for example, the notions of genus, species and the like, which are not found in reality but are a natural result of the consideration of reason. And this kind of being, i.e., being of reason, constitutes the proper subject of logic. But intellectual conceptions of this kind are equal in extension to real beings, because all real beings fall under the consideration of reason. Hence the subject of logic extends to all things to which the expression real being is applied. His conclusion is, then, that the subject of logic is equal in extension to the subject of philosophy, which is real being.
Now the philosopher proceeds from the principles of this kind of being to prove the things that have to be considered about the common accidents of this kind of being. But the dialectician proceeds to consider them from the conceptions of reason, which are extrinsic to reality. Hence it is said that dialectics is in search of knowledge, because in searching it is proper to proceed from extrinsic principles.
575. But the philosopher differs from the sophist “in the choice,” i.e., in the selection or willing, or in the desire, of a way of life. For the philosopher and sophist direct their life and actions to different things. The philosopher directs his to knowing the truth, whereas the sophist directs his so as to appear to know what he does not.
576. Now although it is said that philosophy is scientific knowledge, and that dialectics and sophistry are not, this still does not do away with the possibility of dialectics and sophistry being sciences. For dialectics can be considered both from the viewpoint of theory and from that of practice. (1) From the viewpoint of theory it studies these conceptions and establishes the method by which one proceeds from them to demonstrate with probability the conclusions of the particular sciences; and it does this demonstratively, and to this extent it is a science. (2) But from the viewpoint of practice it makes use of the above method so as to reach certain probable conclusions in the particular sciences; and in this respect it falls short of the scientific method.
The same must be said of sophistry, because from the viewpoint of theory it treats by means of necessary and demonstrative arguments the method of arguing to apparent truth. From the viewpoint of practice, however, it falls short of the process of true argumentation.
577. But that part of logic which is said to be demonstrative is concerned only with theory, and the practical application of it belongs to philosophy and to the other particular sciences, which are concerned with real beings. This is because the practical aspect of the demonstrative part of logic consists in using the principles of things, from which proceeds demonstration (which properly belongs to the sciences that deal with real beings), and not in using the conceptions of logic.
Thus it appears that some parts of logic are at the same time scientific, theoretical, and practical, as exploratory dialectics and sophistry; and one is concerned with theory and not practice, namely, demonstrative logic.
578. Further, one corresponding (313).
Then he gives the third argument in support of his thesis. It runs as follows: everything that is reducible to unity and being should be considered by the philosopher, whose function is to study unity and being. But all contraries are reducible to unity and being. Therefore all contraries belong to the consideration of the philosopher, whose function is to study unity and being.
579. Then he proves that all contraries are reducible to unity and being. He does this, first, with regard to being; and he proceeds thus: of any two contraries which the philosophers posited as the principles of things, as is said in Book I (62:C 132), one contrary is always the correlative of the other and is related to it as its privation. This is clear from the fact that one of two contraries is always something imperfect when compared with the other, and thus implies some privation of the perfection of the other. But a privation is a kind of negation, as was stated above (306:C 564), and thus is a non-being. Hence it is clear that all contraries are reducible to being and non-being.
580. He also shows by an example that all contraries are reducible to unity and plurality. For rest or repose is reducible to unity, since that is said to be at rest which is in the same condition now as it was before, as is stated in Book VI of the Physics. And motion is reducible to plurality, because whatever is in motion is in a different condition now than it was before, and this implies plurality.
581. And almost all (314).
Then he uses another argument to show that contraries are reducible to being. Both the principles of things and the things composed of them belong to the same study. But the philosophers admit that contraries are the principles of being as being; for all say that beings and the substances of beings are composed of contraries, as was stated in Book I of the Physics and in the first book of this work (62:C 132). Yet while they agree on this point, that the principles of beings are contraries, still they differ as to the contraries which they give. For some give the even and odd, as the Pythagoreans; others the hot and cold, as Parmenides; others “the end” or terminus “and the unlimited,” i.e., the finite and infinite, as did the same Pythagoreans (for they attributed limitedness and unlimitedness to the even and the odd, as is stated in Book I (59:C 124); and still others gave friendship and strife, as Empedocles. Hence it is clear that contraries are reducible to the study of being.
582. And all the other (315).
He says that the above-mentioned contraries are redudible not only to being but also to unity and plurality. This is evident. For oddness by reason of its indivisibility is affiliated with unity, and evenness by reason of its divisibility has a natural connection with plurality. Thus end or limit pertains to unity, which is the terminus of every process of resolution, and lack of limit pertains to plurality, which may be increased to infinity. Again, friendship also clearly pertains to unity, and strife to plurality. And heat pertains to unity inasmuch as it can unite homogeneous things, whereas cold pertains to plurality inasmuch as it can separate them. Further, not only these contraries are reducible in this way to unity and plurality, but so also are the others. Yet this “reduction,” or introduction, to unity and plurality let us now accept or “take for granted,” i.e., let us now assume it, because to examine each set of contraries would be a lengthy undertaking.
583. Next he shows that all contraries are reducible to unity and being. For it is certain that all principles, inasmuch as they have to do “with other things” i.e., the things composed of them, fall under unity and being as their genera, not in the sense that they truly are genera, but in the sense that they bear some likeness to genera by reason of what they have in common. Hence, if all contraries are principles or things composed of principles, they must be reducible to unity and being.Thus it is clear that he shows that contraries are reducible to being for two reasons: first, because of the nature of privation, and second, by reason of the fact that contraries are principles. He shows that they are reducible to unity by giving an example and by using a process of reduction. Last, he shows that they are reducible to unity and being inasmuch as they have the character of genera.
584. It is clear (316).
Here he proves in a converse way that this science considers being because it considers the things mentioned above. His argument is this: all beings are reducible to contraries because they are either contraries or composed of contraries. And contraries are reducible to unity and plurality because unity and plurality are the principles of contraries. But unity and plurality belong to one science, philosophy. Therefore it is the office of this science to consider being as being. Yet it must be noted that all the contraries mentioned above fall under the consideration of one science whether they are used “in one sense,” i.e., univocally, or not, as perhaps is the case. However, even if the term one is used in many senses, all the others, i.e., all the other senses, are reducible to one primary sense. Hence, even if unity or being is not one universal, like a genus, as was stated above (whether a universal is said to be a one-in-all, as we maintain, or something separate from things, as Plato thought, and as is presumably not the case), still each is used in a primary and a secondary sense. And the same holds true in the case of other terms, for some senses are referred to one primary sense, and others are secondary with respect to that primary sense. An adverb designating uncertainty is used inasmuch as we are now assuming things that will be proved below.
585. But nevertheless it must be borne in mind that the statement which he made, that all beings are either contraries or composed of contraries, he did not give as his own opinion but as one which he took from the ancient philosophers; for unchangeable beings are not contraries or composed of contraries. And this is why Plato did not posit any contrariety in the unchangeable sensible substances; for he attributed unity to form and contrariety to matter. But the ancient philosophers claimed that only sensible substances exist and that these must contain contrariety inasmuch as they are changeable.
586. And for this reason (317)
Then he draws a corollary from what has been said. He says that it is not the province of geometry to investigate the foregoing things, which are accidents of being as being, i.e., to investigate what a contrary is, or what the perfect is, and so on. But if a geometer were to consider them, he would “assume them,” i.e., presuppose their truth, inasmuch as he would take them over from some prior philosopher from whom he accepts them insofar as they are necessary for his own subject matter. What is said about geometry must be understood to apply also in the case of any other particular science.
587. It is evident (318).
He now summarizes the points established above. He says that obviously the consideration of being as being and the attributes which belong to it of itself pertain to one science. Thus it is clear that that science considers not only substances but also accidents since being is predicated of both. And it considers the things which have been discussed, namely, sameness and otherness, likeness and unlikeness, equality and inequality, privation and negation, and contraries-which we said above are the proper accidents of being. And it considers not only those things which fall under the consideration of this science, about which demonstration was made individually by means of arguments based on proper principles, but it in like manner also considers prior and subsequent, genus and species, whole and part, and other things of this kind, because these too are accidents of being as being.
LESSON 5
Answers to Questions Raised in Book III about Principles of Demonstration
ARISTOTLE’S TEXT Chapter 3: 1005a 19-1005b 8
319. Moreover, it is necessary to state whether it is the office of one science or of different sciences to inquire about those principles which are called axioms in mathematics, and about substance.
320. Now it is evident that it is the office of one science—that of the philosopher—to investigate these.
321. For these principles apply to all beings and not to some class distinct from the others. And all men employ them, because they pertain to being as being; for each class is being. But they employ them just so far as to satisfy their needs, i.e., so far as the class contains the things about which they form demonstrations. Hence, since it is evident that these principles pertain to all things inasmuch as they are beings (for this is what they have in common), the investigation of them belongs to him who considers being as being.
322. Hence no one who is making a special inquiry attempts to say anything about their truth or falsity, neither the geometer nor the arithmetician.
323. However, some of the philosophers of nature have done this, and with reason; for they thought that they alone were inquiring about the whole of nature and about being. But since there is one kind of thinker who is superior to the philosopher of nature (for nature is only one class of being), the investigation of these principles will belong to him who studies the universal and deals with first substance. The philosophy of nature is a kind of wisdom, but it is not the first.
324. And whatever certain ones of 1 those who speak about the truth attempt to say concerning the way in which it must be accepted, they do this through ignorance of analytics. For they must know these principles in order to attain scientific knowledge and not be seeking them when they are learning a science.
325. It is evident, then, that it is also the business of the philosopher, i.e., of him who investigates all substance insofar as its nature permits, to investigate all syllogistic principles.
COMMENTARY
This science considers the first principles of demonstration.
588. Here he answers another question raised in Book III (387): whether it belongs to this science to consider the first principles of demonstration. This is divided into two parts. In the first he shows that it belongs to this science to make a general study of all these principles; and in the second (596) he shows that it also belongs to it to make a special study of the first of these principles (“And it is fitting”).
In regard to the first he does three things. First, he raises the question whether it belongs to one or to different sciences to consider substance and the principles which are called axioms in the mathematical sciences. He assigns these principles more to the mathematical sciences because such sciences have more certain demonstrations and use these self-evident principles in a more manifest way inasmuch as they refer all of their demonstrations to them.
589. Now it is evident (320).
Second, he answers this question by saying that a single science investigates both of the foregoing things, and that this is the philosophy with which we are now concerned.
590. For these principles (321).
Third, he proves his proposed answer, and in regard to this he does two things. First, he proves it. Second (595), he introduces his main conclusion (“It is evident”).
Now he proves his proposed answer in two ways. He does this, first, by an argument; and second (592), by an example (“Hence no one”).
The argument is as follows: whatever principles pertain to all beings, and not just to one class of beings distinct from the others, belong to the consideration of the philosopher. But the above-mentioned principles are of this kind. Therefore they belong to the consideration of the philosopher. He proves the minor premise as follows. Those principles which all sciences use pertain to being as being. But first principles are principles of this kind. Therefore they pertain to being as being.
591. The reason which he gives for saying that all sciences use these principles is that the subject genus of each science has being predicated of it. Now the particular sciences do not use the foregoing principles insofar as they are common principles, i.e., as extending to all beings, but insofar as they have need of them; that is, insofar as they extend to the things contained in the class of beings which constitutes the subject of a particular science about which it makes demonstrations. For example, the philosophy of nature uses them insofar as they extend to changeable beings and no further.
592. Hence no one (322).
Then he proves what he had said by using an example. First, he introduces the proof; and second (593), he rejects a false notion held by some men (“However, some”).
He accordingly says, first, that no one whose chief intention is to hand down scientific knowledge of some particular being has attempted to say anything about the truth or falsity of first principles. Neither the geometer nor the arithmetician does this even though they make the greatest use of these principles, as was said above (588). Hence it is evident that the investigation of these principles belongs to this science.
593. However, some (323).
Here he rejects the false notion held by some men, and in regard to this he does two things. First, he rejects the false notion of those who occupied themselves with these principles even though they did not concern them. Second, (594), he rejects the false notion of those who wanted to deal with these principles in a different way than they should be dealt with.
He accordingly says, first, that even though none of the particular sciences ought to deal with the above-mentioned principles, nevertheless some of the natural philosophers have dealt with them; and they did so not without reason. For the ancients did not think that there was any substance besides the changeable corporeal substance with which the philosophy of nature is concerned. Hence they believed that they alone established the truth about the whole of nature and therefore about being, and thus about first principles, which must be considered along with being. But this is false, because there is still a science which is superior to the science of nature. For nature itself, i.e., natural being, which has its own principle of motion, constitutes in itself one class of universal being.
But not every being is of this kind, because it has been proved in the Physics, Book VIII, that an unchangeable being exists. Now this unchangeable being is superior to and nobler than changeable being, with which the philosophy of nature is concerned. And since the consideration of common being belongs to that science which studies the primary kind of being, then the consideration of common being belongs to a different science than the philosophy of nature. And the consideration of common principles of this kind will also belong to this science. For the philosophy of nature is a part of philosophy but not the first part, which considers common being and those attributes which belong to being as being.
594. And whatever (324).
Then he rejects the other false notion, which concerns the way in which such principles should be treated. For some men investigated these principles with the aim of demonstrating them. And whatever they said about the truth of these principles, i.e., how they must be accepted as true by force of demonstration, or how the truth found in all these principles must be reached, they did through ignorance of, or lack of skill in, “analytics,” which is that part of logic in which the art of demonstration is treated. For “they must know these principles in order to attain scientific knowledge”; i.e., every science acquired by demonstration depends on these principles.
But “those who are learning,” i.e., the pupils who are being instructed in some science, must not seek these principles as something to be demonstrated. Or, according to another text, “those who have scientific knowledge must attain science from these principles”; i.e., those who attain knowledge by demonstration must come to know common principles of this kind and not ask that they be demonstrated to them.
595. It is evident (325).
He draws the conclusion primarily intended, namely, that it will be the function of the philosopher to consider every substance as such and also the first syllogistic principles. In order to make this clear it must be noted that self-evident propositions are those which are known as soon as their terms are known, as is stated in Book I of the Posterior Analytics. This occurs in the case of those propositions in which the predicate is given in the definition of the subject, or is the same as the subject. But it happens that one kind of proposition, even though it is self-evident in itself, is still not self-evident to all, i.e., to those who are ignorant of the definition of both the subject and the predicate. Hence Boethius says in De Hebdomadibus that there are some propositions which are self-evident to the learned but not to all. Now those are self-evident to all whose terms are comprehended by all. And common principles are of this kind, because our knowledge proceeds from common principles to proper ones, as is said in Book I of the Physics. Hence those propositions which are composed of such common terms as whole and part (for example, every whole is greater than one of its parts) and of such terms as equal and unequal (for example, things equal to one and the same thing are equal to each other), constitute the first principles of demonstration. And the same is true of similar terms. Now since common terms of this kind belong to the consideration of the philosopher, then it follows that these principles also fall within his scope. But the philosopher does not establish the truth of these principles (~) by way of demonstration, but (+) by considering the meaning of their terms. For example, he considers what a whole is and what a part is; and the same applies to the rest. And when the meaning of these terms becomes known, it follows that the truth of the above-mentioned principles becomes evident.
LESSON 6
First Philosophy Must Examine the First Principle of Demonstration. The Nature of This Principle. The Errors about It
ARISTOTLE’S TEXT Chapters 3 & 4: 1005b 8-1006a 18
326. And it is fitting that the person who is best informed about each class of things should be able to state the firmest principles of his subject. Hence he who understands beings as beings should be able to state the firmest principles of all things. This person is the philosopher.
327. And the firmest of all principles is that about which it is impossible to make a mistake; for such a principle must be both the best known (for all men make mistakes about things which they do not know) and not hypothetical. For the principle which everyone must have who understands anything about beings is not hypothetical; and that which everyone must know who knows anything must be had by him when he comes to his subject. It is evident, then, that such a principle is the firmest of all.
328. And let us next state what this principle is. It is that the same attribute cannot both belong and not belong to the same subject at the same time and in the same respect; and let us stipulate any other qualifications that have to be laid down to meet dialectical difficulties. Now this is the firmest of all principles, since it answers to the definition given; for it is impossible for anyone to think that the same thing both is and is not, although some are of the opinion that Heraclitus speaks in this way; for what a man says he does not necessarily accept. But if it is impossible for contraries to belong simultaneously to the same subject (and let us then suppose that the same things are established here as in the usual proposition), and if one opinion which expresses the contradictory of another is contrary to it, evidently the same man at the same time cannot think that the same thing can both be and not be; for one who is mistaken on this point will have contrary opinions at the same time. And it is for this reason that all who make demonstrations reduce their argument to this ultimate position. For this is by nature the starting point of all the other axioms.
Chapter 4
329. Now as we have said (328), there are some who claimed that the same thing can both be and not be, and that this can be believed. And many of those who treat of nature adopt this theory. But now we take it to be impossible for a thing both to be and not be at the same time, and by means of this we shall show that this is the firmest of all principles.
330. But some deem it fitting that even this principle should be demonstrated, and they do this through want of education. For not to know of what things one should seek demonstration and of what things one should not shows want of education. For it is altogether impossible that there should be demonstration of all things, because there would then be an infinite regress so that there would still be no demonstration. But if there are some things of which it is not necessary to seek demonstration, these people cannot say what principle they think to be more indemonstrable.
331. But even in this case it is possible to show by refutation that this view is impossible, if only our opponent will say something. But if he says nothing, it is ridiculous to look for a reason against one who has no reason, on the very point on which he is without reason; for such a man is really like a plant. Now I say that demonstration by refutation is different from demonstration [in the strict sense], because he who would demonstrate this principle in the strict sense would seem to beg the question. But when someone argues for the sake of convincing another there will be refutation, not demonstration.
COMMENTARY
This science considers particularly the very first principle, that of contradiction.
596. He shows here that it is the first philosopher who is chiefly concerned with the first principle of demonstration; and in regard to this he does two things. First, he shows that it is the business of the first philosopher to consider this principle; and second (611), he begins to examine this principle.
In regard to the first he does three things.. First, he shows that it is the office of this science to consider the first principle of demonstration. Second (597), he indicates what this principle is. Third (606), he rejects certain errors regarding this same principle.
In regard to the first point he uses the following argument. In every class of things that man is best informed who knows the most certain principles, because the certitude of knowing depends on the certitude of principles. But the first philosopher is best informed and most certain in his knowledge; for this was one of the conditions of wisdom, as was made clear in the prologue of this work (35), namely, that he who knows the causes of things has the most certain knowledge. Hence the philosopher ought to consider the most certain and firmest principles of beings, which he considers as the subject-genus proper to himself.
597. And the firmest (327).
Then he shows what the firmest or most certain principle is; and in regard to this he does two things. First, he states the conditions for the most certain principle; and then (600) he shows how they fit a single principle (“And let us”).
He accordingly gives, first, the three conditions for the firmest principle. (1) The first is that no one can make a mistake or be in error regarding it. And this is evident because, since men make mistakes only about those things which they do not know, then that principle about which no one can be mistaken must be the one which is best known.
598. (2) The second condition is that it must “not be hypothetical,” i.e., it must not be held as a supposition, as those things which are maintained through some kind of common agreement. Hence another translation reads “And they should not hold a subordinate place,” i.e., those principles which are most certain should not be made dependent on anything else. And this is true, because whatever is necessary for understanding anything at all about being “is not hypothetical,” i.e., it is not a supposition but must be self-evident. And this is true because whatever is necessary for understanding anything at all must be known by anyone who knows other things.
599. (3) The third condition is that it is not acquired (~) by demonstration or by any similar method, but (+) it comes in a sense by nature to the one having it inasmuch as it is naturally known and not acquired. For first principles become known through the natural light of the agent intellect, and they are not acquired by any process of reasoning but by having their terms become known. This comes about by reason of the fact that memory is derived from sensible things, experience from memory, and knowledge of those terms from experience. And when they are known, common propositions of this kind, which are the principles of the arts and sciences, become known.
Hence it is evident that the most certain or firmest principle should be such that there can be no error regarding it; that it is not hypothetical; and that it comes naturally to the one having it.
600. And let us next (328).
Then he indicates the principle to which the above definition applies. He says that it applies to this principle, as the one which is firmest: it is impossible for the same attribute both to belong and not belong to the same subject at the same time. And it is necessary to add “ in the same respect ”; and any other qualifications that have to be given regarding this principle “to meet dialectical difficulties” must be laid down, since without these qualifications there would seem to be a contradiction when there is none.
601. That this principle must meet the conditions given above he shows as follows: (1) It is impossible for anyone to think, or hold as an opinion, that the same thing both is and is not at the same time, although some believe that Heraclitus was of this opinion. But while it is true that Heraclitus spoke in this way, he could not think that this is true; for it is not necessary that everything that a person says he should mentally an opinion.
602. But if one were to say that it is possible for someone to think that the same thing both is and is not at the same time, this absurd consequence follows: contraries could belong to the same subject at the same time. And “let us suppose that the same things are established,” or shown, here as in the usual proposition established in our logical treatises. For it was shown at the end of the Peri hermineas I that contrary opinions are not those which have to do with contraries but those which have to do with contradictories, properly speaking. For when one person thinks that Socrates is white and another thinks that he is black, these are not contrary opinions in the primary and proper sense; but contrary opinions are had when one person thinks that Socrates is white and another thinks that he is not white.
603. Therefore, if someone were to think that two contradictories are true at the same time by thinking that the same thing both is and is not at the same time, he will have contrary opinions at the same time; and thus contraries will belong to the same thing at the same time. But this is impossible. It is impossible, then, for anyone to be mistaken in his own mind about these things and to think that the same thing both is and is not at the same time. And it is for this reason that all demonstrations reduce their propositions to this proposition as the ultimate opinion common to all; for this proposition is by nature the starting point and axiom of all axioms.
604. (2 & 3) The other two conditions are therefore evident, because, insofar as those making demonstrations reduce all their arguments to this principle as the ultimate one by referring them to it, evidently this principle is not based on an assumption. Indeed, insofar as it is by nature a starting point, it clearly comes unsought to the one having it and is not acquired by his own efforts.
605. Now for the purpose of making this evident it must be noted that, since the intellect has two operations, one by which it knows quiddities, which is called the understanding of indivisibles, and another by which it combines and separates, there is something first in both operations. In the first operation the first thing that the intellect conceives is being, and in this operation nothing else can be conceived unless being is understood.
And because this principle—it is impossible for a thing both to be and not be at the same time—depends on the understanding of being (just as the principle, every whole is greater than one of its parts, depends on the understanding of whole and part), then this principle is by nature also the first in the second operation of the intellect, i.e., in the act of combining and separating. And no one can understand anything by this intellectual operation unless this principle is understood. For just as a whole and its parts are understood only by understanding being, in a similar way the principle that every whole is greater than one of its parts is understood only if the firmest principle is understood.
606. Now as we have said (329).
Then he shows how some men erred regarding this principle; and in regard to this he does two things. First, he touches on the error of those who rejected the foregoing principle; and second (607) he deals with those who wished to demonstrate it (“But some”).
He accordingly says that some men as was stated above about Heraclitus (601), said that the same thing can both be and not be at the same time, and that it is possible to hold this opinion; and many of the philosophers of nature adopt this position, as will be made clear below (665). For our part, however, we now take as evident that the principle in question is true, i.e., the principle that the same thing cannot both be and not be; but from its truth we show that it is most certain. For from the fact that a thing cannot both be and not be it follows that contraries cannot belong to the same subject, as will be said below (663). And from the fact that contraries cannot belong to a subject at the same time it follows that a man cannot have contrary opinions and, consequently, that he cannot think that contradictories are true, as has been shown (603).
607. But some (330).
Then he mentions the error of certain men who wished to demonstrate the above-mentioned principle; and in regard to this he does two things. First, he shows that it cannot be demonstrated in the strict sense; and second (608), that it can be demonstrated in a way (“But even”).
Thus he says, first, that certain men deem it fitting, i.e., they wish, to demonstrate this principle; and they do this “through want of education,” i.e., through lack of learning or instruction. For there is want of education when a man does not know what to seek demonstration for and what not to; for not all things can be demonstrated. For if all things were demonstrable, then, since a thing is not demonstrated through itself but through something else, demonstrations would either be circular (although this cannot be true, because then the same thing would be both better known and less well known, as is clear in Book I of the Posterior Analytics, or they would have to proceed to infinity. But if there were an infinite regress in demonstrations, demonstration would be impossible, because the conclusion of any demonstration is made certain by reducing it to the first principle of demonstration. But this would not be the case if demonstration proceeded to infinity in an upward direction. It is clear, then, that not all things are demonstrable. And if some things are not demonstrable, these men cannot say that any principle is more indemonstrable than the above-mentioned one.
608. But even in this case (331).
Here he shows that the above-mentioned principle can be demonstrated in a certain respect. He says that it may be demonstrated by disproof. In Greek the word is evlegktikw/j, which is better translated as by refutation, for an e;legkoj is a syllogism that establishes the contradictory of a proposition, and so is introduced to refute some false position. And on these grounds it can be shown that it is impossible for the same thing both to be and not be.
But this kind of argument can be employed only if the one who denies that principle because of difficulties “says something,” i.e., if he signifies something by a word. But if he says nothing, it is ridiculous to look for a reason against one who does not make use of reason in speaking; for in this dispute anyone who signifies nothing will be like a plant, for even brute animals signify something by such signs.
609. For it is one thing to give a strict demonstration of this principle, and another to demonstrate it argumentatively or by refutation. For if anyone wished to give a strict demonstration of this principle, he would seem to be begging the question, because any principle that he could take for the purpose of demonstrating this one would be one of those that depend on the truth of this principle, as is clear from what has been said above (330:C 607). But when the demonstration is not of this kind, i.e., demonstration in the strict sense, there will then be disproof or refutation at most.
610. Another text states this better by saying, “But when one argues for the sake of convincing another, there will then be refutation but not demonstration”; i.e., when a process of this kind from a less well known to a better known principle is employed for the sake of convincing another man who denies this, there will then be disproof or refutation but not demonstration; i.e., it will be possible to have a syllogism which contradicts his view, since what is less known absolutely is admitted by the opponent, and thus it will be possible to proceed to demonstrate the above-mentioned principle so far as the man is concerned but not in the strict sense.
LESSON 7
Contradictories Cannot Be True at the Same Time
ARISTOTLE’S TEXT Chapter 4: 1006a 18-1007b 18
332. The starting point of all such discussions is not the desire that someone shall state that something either is or is not, for this might perhaps be thought to be begging the question, but that he shall state something significant both for himself and for someone else; for this he must do if he is to say anything. For if he does not, no discussion will be possible for such a person either with himself or with another. But if anyone will grant this, demonstration will be possible; for there will already be something definite. But this will not have the effect of demonstrating but of upholding, for he who destroys reason upholds reason.
333. First of all, then, it is evident that this at least is true, that the term to be or not to be signifies something, so that not everything will be so and not so.
334. Again, if the term man signifies one thing, let this be a twofooted animal.
335. Now by signifying one thing I mean this: granted that man is a twofooted animal, then if something is a man, this will be what being a man is. And it makes no difference even if someone were to say that this term signifies many things, provided that there are a definite number; for a different term might be assigned to each concept. I mean, for example, that if one were to say that the term man signifies not one thing but many, one of which would have a single concept, namely, two-footed animal, there might still be many others, if only there are a limited number; for a particular term might be assigned to each concept. However, if this were not the case, but one were to say that a term signifies an infinite number of things, evidently reasoning would be impossible; for not to signify one thing is to signify nothing. And if words signify nothing, there will be no discourse with another or even with ourselves. For it is impossible to understand anything unless one understands one thing; but if this does happen, a term may be assigned to this thing. Let it be assumed, then, as we said at the beginning (332), that a term signifies something, and that it signifies one thing.
336. It is impossible, then, that being a man should mean not being a man, if the term man not only signifies something about one subject but also signifies one thing. For we do not think it fitting to identify signifying one thing with signifying something about one subject, since the terms musical, white and man would then signify one thing. And therefore all things would be one, because all would be synonymous. And it will be impossible to be and not to be the same thing, except in an equivocal sense, as occurs if one whom we call man others call not-man. But the problem is not whether the same thing can at the same time be and not be a man in name, but whether it can in fact.
337. Now if man and not-man do not signify something different, it is evident that not being a man will not differ from being a man. Thus being a man will be identical with not being a man, for they will be one thing. For being one means this: being related as clothing and garment are, if they are taken in the same sense. And if being a man and not being a man are to be one, they must signify one thing. But it has been shown that they signify different things.
338. Therefore, if it is true to say that something is a man, it must be a two-footed animal, for this is what the term man signifies. But if this is necessary, it is impossible for this very thing not to be a two-footed animal; for this is what to-be-necessary means, namely, unable not to be. Hence it cannot be true to say that the same thing is and is not a man at the same time. The same argument also applies to not being a man.
339. For being a man and not being a man signify different things, since being white and being a man are different; for there is much greater opposition in the former case, so that they signify different things. And if one were to say also that white signifies the same thing as man and is one in concept, we shall say the same thing as was said before (335), namely, that all things are one, and not merely opposites. But if this is impossible, then what has been said will follow.
340. That is to say, it will follow if our opponent answers the question. And if in giving a simple answer to the question he also adds the negations, he is not answering the question. For there is nothing to prevent the same thing from being man and white and a thousand other things numerically. Still if one asks whether it is or is not true to say that this is a man, his opponent should reply by stating something that means one thing and not add that it is also white or black or large. Indeed, it is impossible to enumerate the accidents of being, which are infinite in number; so therefore let him enumerate either all or none. Similarly, even if the same thing is a thousand times a man and a not-man, he must not, in answering the question whether this is a man, add that it is also at the same time a not-man, unless he also gives all the other corresponding accidents, whatever are so or are not so. And if he does not do this, there will be no debate with him.
341. And those who say this do away completely with substance or essence, for they must say that all attributes are accidents, and that there is no such thing as being a man or being an animal. For if there is to be such a thing as being a man, this will not be being a not-man or not being a man; in fact these are the negations of it. For there was one thing which the term signified, and this was the substance of something. And to signify the substance of a thing is to signify that its being is not something else. And if being essentially a man is being essentially a not-man, then the being of man will be something else. Hence they are compelled to say that nothing will have such a concept as this, but that all attributes are accidental. For this distinguishes substance from accident; for white is an accident of man, because while some man is white he is not the essence of whiteness.
342. Moreover, if all attributes are accidental predicates, there will be no first universal. And if the accidental always implies a predication about some subject, the process must go on to infinity. But this is impossible; for not more than two terms are combined in accidental predication. For an accident is an accident of an accident only because both are accidents of the same subject. I mean, for example, that white is an accident of musical and musical of white’ only because both are accidental to man; but Socrates is not musical in the sense that both are accidental to something else. Therefore, since some accidents are predicated in the latter and some in the former sense, all those that are predicated as white is predicated of Socrates cannot form an infinite series in an upward direction so that there should be another accident of white Socrates; for no one thing results from all of these. Nor again will white have another accident, such as musical; for this is no more an accident of that than that of this. And at the same time it has been established that some things are accidents in this sense and some in the sense that musical is an accident of Socrates. And whatever attributes are predicated accidentally in the latter sense are not accidents of accidents but only those predicated in the former sense. Not all attributes, then, are said to be accidents; and thus there must be some term which also signifies substance. And if this is so, then we have proved that contradictories cannot be predicated at the same time of the same subject.
COMMENTARY
611. Here he begins to argue dialectically against those who deny the foregoing principle, and this is divided into two parts. In the first (332:C 611) he argues against those who say that contradictories are true at the same time; and in the second (383:C 720), against those who say that they are false at the same time (“Neither can there be”).
In regard to the first he does two things. First, he argues in a general way against those who make the aforesaid errors. Second (353:C 663), he shows how we must argue specifically against different positions (“But the same method”).
In regard to the first he does two things. First, he argues dialectically against the reasoning of those who deny the foregoing principle. Second (352:C 661), he shows that Protagoras’ opinion is fundamentally the same as the one just mentioned (“The doctrine of Protagoras”).
In regard to the first point he gives seven arguments. He gives the second (341:C 624) at the words “And those who”; the third (343:C 636) at “Furthermore, if all”; the fourth (347:C 642) at “Again, either this”; the fifth (348:C 652) at “Again, how”; the sixth (349:C 654) at “It is most evident”; and the seventh (351:C 65.9) at “Further, even if all.”
In regard to the first he does two things. First, he indicates the starting point from which one must proceed to argue against those who deny the first principle. Second (333:C 612), he proceeds to argue from that starting point (“First of all, then”).
He therefore says, first (332), that with respect to all such unreasonable positions there is no need for us to take as a starting point that someone `wishes to suppose that this thing definitely is “or is not”; i.e., it is not necessary to take as a starting point some proposition in which some attribute is either affirmed or denied of a subject (for this would be a begging of the question, as was said above [331:C 609]), but it is necessary to take as a starting point that a term signifies something both to the one who utters it, inasmuch as he himself understands what he is saying, and to someone else who hears him. But if such a person does not admit this, he will not say anything meaningful either for himself or for someone else, and it will then be idle to dispute with him. But when he has admitted this, a demonstration
will at once be possible against him; for there is straightway found to be something definite and determinate which is signified by the term distinct from its contradictory, as will become clear below. Yet this will not strictly be a demonstration of the foregoing principle but only an argument upholding this principle against those who deny it. For he who “destroys reason,” i.e., his own intelligible expression, by saying that a term signifies nothing, must uphold its significance, because he can only express what he denies by speaking and by signifying something.
612. First of all, then (333).
He proceeds from the assumption he had made to prove what he intends. First, he deals with one particular case; and second (334:C 612), he treats all cases in a general way (“Again, if the term”).
He accordingly says, first (333), that if a term signifies something, it will be evident first of all that this proposition will be true, and that its contradictory, which he denies, will be false; and thus this at least will be true, that not every affirmation is true together with its negation.
613. Now by signifying (535).
Then he shows that this applies universally to all cases, namely, that contradictories are not true at the same time. In regard to this he does four things. First, he makes certain assumptions which are necessary for drawing his intended conclusion. Second (338:C 620), he draws his conclusion (“Therefore, if it is true”). Third (339:C 622), he proves one assumption which he had made (“For being a man”). Fourth (340:C 623), he rejects a quibble (“That is to say”).
In regard to the first he does three things. First, he shows that a term signifies one thing; and second (336:C 616), he shows from this that the term man signifies what being a man is, but not what it is not (“It is impossible, then”). Third (337:C 61g), he shows that the term man signifies one thing (“Now if man”).
He accordingly says, first (335), that if the term man signifies one thing, let this be two-footed animal. For a term is said to signify this one thing which is the definition of the thing signified by the term, so that if “twofooted animal” is the being of man, i.e., if this is what the essence of man is, this will be what is signified by the term man.
614. But if one were to say that a term signifies many things, it will signify either a finite or an infinite nurnher of them. But if it signifies a finite number, it will differ in no way, according to another translation, from the term which is assumed to signify one thing; for it signifies many finite concepts of different things, and different terms can be fitted to each single concept. For example, if the term man were to signify many concepts, and the concept two-footed animal is one of them, one term is assigned to the concept man. And if there are many other concepts, many other terms may be assigned so long as those concepts are finite in number. Thus he will be forced back to the first position, that a term signifies one thing.
615. But if a term does not signify a finite but an infinite number of concepts, evidently neither reasoning nor debate will be possible. This becomes clear as follows: any term that does not signify one thing signifies nothing. This is proved thus: terms signify something understood, and therefore if nothing is understood, nothing is signified. But if one thing is not understood, nothing is understood, because anyone who understands anything must distinguish it from other things. If a term does not signify one thing, then, it signifies nothing at all; and if terms signify nothing, discourse will be impossible, both the kind which establishes truth and the kind which refutes an assertion. Hence it is clear that, if terms signify an infinite number of things, neither reasoning nor dispute will be possible. But if it is possible to understand one thing, a term may be given to it. So let it be held then that a term signifies something.
616. It is impossible (336).
He proves the second point, namely, that the term man does not signify not being a man; for a term that signifies one thing signifies not only what is one in subject (and is therefore said to be one because it is predicated of one subject) but what is one absolutely, i.e., in concept. For if we wanted to say that a term signifies one thing because it signifies the attributes which are verified of one thing, it would then follow that the terms musical, white and man all signify one thing, since all are verified of one thing. And from this it would follow that all things are one; for if white is predicated of man and is therefore identical with him, then when it is also predicated of a stone it will be identical with a stone; and since those things which are identical with one and the same thing are identical with each other, it would follow that a man and a stone are one thing and have one concept. Thus the result would be that all terms are univocal, i.e., one in concept, or synonymous, as another text says, i.e., meaning absolutely the same thing in subject and in concept.
617. Now although being and nonbeing are verified of the same subject according to those who deny the first principle, still being a man and not being a man must differ in concept, just as white and musical differ in concept even though they are verified of the same subject. Hence it is evident that being and non-being cannot be the same in concept and in subject in the sense that they are signified by one univocal term.
618. Now it must be noted that the expression being a man or to be a man or having the being of a man is taken here for the quiddity of man, and therefore it is concluded from this that the term man does not signify not being a man as its proper concept. But because he had said above (335:C 614) that the same term can signify many things according to different concepts, he therefore adds “except in an equivocal sense” in order to make clear that the term man does not signify in a univocal sense both being a man and not being a man, but it can signify both in an equivocal sense; i.e., in the sense that what we call man in one language others might call not-man in another language. For we are not debating whether the same thing can both be and not be man in name, but whether it can in fact.
619. Now if man (337).
Then he proves the third point: that the terms man and not-man do not signify the same thing, and he uses the following argument. The term man signifies being a man or what man is, and the term not-man signifies not being a man or what man is not. If, then, man and not man do not signify something different, being a man will not differ from not being a man, or being a n6t-man, and therefore one of these will be predicated of the other. And they will also have one concept; for when we say that some terms signify one thing, we mean that they signify one concept, as the terms clothing and garment do. Hence, if being a man and not being a man are one in this way, i.e., in concept, there will then be one concept which will signify both being a man and not being a man. But it has been granted or demonstrated that the term which signifies each is different; for it has been shown that the term man signifies man and does not signify not-man. Thus it is clear that being a man and not being a man do not have a single concept, and therefore the thesis that man and not-man signify different things becomes evident.
620. Therefore, if it is true (338).
Here he proves his main thesis from the assumptions made earlier, and he uses the following argument. A man must be a two-footed animal, as is true from the foregoing, for this is the concept which the term man signifies. But what is necessary cannot not be; for this is what the term necessary means, namely, unable not to be, or incapable of not being, or impossible not to be. Hence it is not possible, or incapable, or impossible for man not to be a two-footed animal, and therefore it is evident that the affirmation and the negation cannot both be true; i.e., it cannot be true that man is both a two-footed animal and not a two-footed animal. The same reasoning based on the meanings of terms can be understood to apply to what is not-man, because what is not-man must be not a two-footed animal, since this is what the term signifies. Therefore it is impossible that a not-man should be a two-footed animal.
621. Now the things demonstrated above are useful to his thesis, because if someone were to think that the terms man and not-man might signify the same thing, or that the term man might signify both being a man and not being a man, his opponent could deny the proposition that man must be a two-footed animal. For he could say that it is no more necessary to say that man must be a two-footed animal than to say that he is not a two-footed animal, granted that the terms man and not-man signify the same thing, or granted that the term man signifies both of these-being a man and not being a man.
622. For being a man (339)
Then he proves one of the assumptions which he had made; for in order to prove that the term man does not signify not being a man, he assumed that being a man and not being a man are different, even though they might be verified of the same subject. His aim here is to prove this by the following argument. There is greater opposition between being a man and not being a man than between man and white; but man and white have different concepts, although they may be the same in subject. Therefore being a man and not being a man also have different concepts. He proves the minor thus: if all attributes which are predicated of the same subject have the same concept and are signified by one term, it follows that all are one, as has been stated and explained (336:C 616). Now if this is impossible, the position we have maintained follows, namely, that being a man and not being a man are different. And for this reason the final conclusion given above will follow, namely, that man is a two-footed animal, and that it is impossible for him to be what is not a two-footed animal.
623. That is to say (340).
He rejects one quibble by which the foregoing process of reasoning could be obstructed. For when an opponent has been asked whether man must be a two-footed animal, he need not reply either affirmatively or negatively but could say that man must be both a two-footed animal and not a two-footed animal. But the philosopher rejects this here, saying that the foregoing conclusion follows so long as an opponent wishes to give a simple answer to the question. But if in giving a simple answer to the question on the side of the affirmative he also wishes to include in his answer the negative aspect, he will not be answering the question. He proves this as follows. One and the same thing can be both a man and white and a thousand other things of this kind. Yet if it is asked here whether a man is white, we must give in our answer only what is signified by one word, and not add all the other attributes. For example, if one asks whether this is a man, we must answer that it is a man, and not add that it is both a man and white and large and the like; for we must give either all of the accidents of a thing at once or not. But not all accidents can be given at once since they are infinite in number; for there are an infinite number of accidents belonging to one and the same thing by reason of its relationship to an infinite number of antecedents and consequents, and what is infinite in number cannot be traversed. In answering the question, then, we must not give any of the attributes which are accidental to the thing about which the question is raised but only the attribute which is asked for. Hence, even if it is supposed a thousand times that man and not-man are the same, still, when the question is asked about man, the answer must not include anything about not-man, unless all those things which are accidental to man are given. And if this were done, no dispute would be possible, because it would never reach completion, since an infinite number of things cannot be traversed.
624. And those who (341).
Then he gives the second argument, and it is based on the notion of substantial and accidental predicates. This is his argument: if an affirmation and a negation are verified of the same subject, it follows that no term will be predicated quidditatively, or substantially, but only accidentally; and therefore there will have to be an infinite regress in accidental predicates. But the consequent is impossible, and thus the antecedent must be impossible.
625. In this argument he does two things. First, he gives a conditional proposition. Second (342:C 629), he gives a proof that destroys the consequent (“Moreover, if all”).
Regarding the first part he proceeds as follows. He says that those who state that an affirmation ind a negation may lie true at the same time completely do away with “substance,” i.e., with a
substantial predicate, “or essence,” i.e., with an essential predicate; for they must say “that all attributes are accidents,” or accidental predicates, and that there is no such thing as being a man or being an animal, and that what the quiddity of man or the quiddity of animal signifies does not exist.
626. He proves this as follows: if there is something which is being a man, i.e., which is the substantial essence of man, which is predicated of man, it will not be not being a man or being a not-man; for these two, i.e., not being a man and being a not-man, are the negations of being a man. It is clear, then, that an affirmation and a negation are not verified of the same subject, for not being a man or being a not-man is not verified of being a man.
627. And the assumption made, namely, that if there is such a thing as being a man, this will not be not being a man or being a not-man, he proves in the following way. It was posited and proved above that the thing which a term signifies is one. And it was also posited that the thing which a term signifies is the substance of something, namely, a thing’s quiddity. Hence it is clear that some term signifies a thing’s substance, and that the thing which was signified is not something else. Therefore, if the essence or quiddity of man should be either not being a man or being a not-man, it is quite clear that it would differ from itself. It would be necessary to say, then, that there is no definition signifying a thing’s essence. But from this it would follow that all predicates are accidental ones.
628. For substance is distinguished from accident, i.e., a substantial predicate is distinguished from an accidental one, in that each thing is truly what is predicated substantially of it. Thus it cannot be said that a substantial predicate is not one thing, for each thing exists only if It is one. But man is said to be white because whiteness or white is one of his accidents, although not in such a way that he is the very essence of white or whiteness. It is not necessary, then, that an accidental predicate should be one only, but there can be many accidental predicates. A substantial predicate, however, is one only; and thus it is clear that what being a man is is not what not being a man is. But if a substantial predicate is both, it will no longer be one only, and thus will not be substantial but accidental.
629. Moreover, if all (342).
He destroys the consequent. He shows that it is impossible that all predicates should be accidental and none substantial because, if all were accidental, there would be no universal predicate. (And universal predicate here means the same thing as it does in the Posterior Analytics, i.e., an attribute which is predicated of something in virtue of itself and in reference to what it itself is). But this is impossible; for if one attribute is always predicated of another accidentally, there will be an infinite regress in accidental predication; but this is impossible for this reason.
630. For there are only two ways in which accidental predication occurs. One way is had when one accident is predicated accidentally of another; and this happens because both are accidents of the same subject, for example, when white is predicated of musical because both are accidents of man. The other way is had when an accident is predicated of a subject (as when Socrates is said to be musical), not because both are accidents of some other subject, but because one of them is an accident of the other. Hence, even though there are two ways in which accidents may be predicated, in neither way can there be an infinite regress in predication.
631. For it is clear that there cannot be an infinite regress in that way in which one accident is predicated of another, because one must reach some subject. For it has been stated already that the essential note of this kind of predication is that both accidents are predicated of one subject. And thus by descending from a predicate to a subject, the subject itself can be found to be the terminus.
632. And there cannot be an infinite regress in an upward direction in the way of predicating in which an accident is predicated of a subject, as when Socrates is said to be white, by ascending from a subject to a predicate so as to say that white is an accident of Socrates and that some other attribute is an accident of white Socrates. For this could occur only in two ways. One way would be that one thing would come from white and Socrates; and thus just as Socrates is one subject of whiteness, in a similar way white Socrates would be one subject of another accident. But this cannot be so, because one thing does not come from all of these predicates. For what is one in an absolute sense does not come from a substance and an accident in the way that one thing comes from a genus and a difference. Hence it cannot be said that white Socrates is one subject.
633. The other way would be that, just as Socrates is the subject of whiteness, in a similar way some other accident, such as musical, would have whiteness as its subject. But neither can this be so, and for two reasons. First, there can be no special reason why musical should be said to be an accident of white rather than the reverse; neither white nor musical will be prior to the other, but they will rather be of equal rank. Second, in conjunction with this it has been established or determined at the same time that this way of predicating in which an accident is predicated of an accident differs from that in which an accident is predicated of a subject, as when musical is predicated of Socrates. But in the way of which he is now speaking accidental predication does not mean that an accident is predicated of an accident; but it is to be so taken in the way we first described.
634. It is evident, then, that an infinite regress in accidental predication is impossible, and therefore that not all predications are accidental. And it is also evident that there will be some term which signifies substance; and again, that contradictories are not true of the same subject.
635. Now with regard to the argument given it must be noted that, even though one accident is not the subject of another, and thus one accident is not related to the other as its subject, still one is related to the other as cause and thing caused. For one accident is the cause of another. Heat and moistness, for example, are the cause of sweetness, and surface is the cause of color. For by reason of the fact that a subject is receptive of one accident it is receptive of another.
LESSON 8
Other Arguments Against the Foregoing Position
ARISTOTLE’S TEXT Chapter 4: 1007b 18-1008b 2
343. Furthermore, if all contradictories are true of the same subject at the same time, it is evident that all things will be one. For the same thing will be a trireme, a wall and a man, if it is possible either to affirm or to deny anything of everything.
344. And this is what must follow for those who agree with Protagoras’ view. For if it appears to anyone that a man is not a trireme, it is evident that he is not a trireme; so that he also is a trireme if contradictories are true. And thus there arises the view of Anaxagoras that all things exist together at the same time, so that nothing is truly one. Hence they seem to be speaking about the indeterminate; and while they think they are speaking about being, they are speaking about non-being; for the indeterminate is what exists potentially and is not complete.
345. But the affirmation and the negation of every predicate of every subject must be admitted by them; for it would be absurd if each subject should have its own negation predicated of it while the negation of something else which cannot be predicated of it should not be predicated of it. I mean that, if it is true to say that a man is not a man, evidently it is also true to say that he is not a trireme. Therefore, if the affirmation is predicable of him, so also must the negation be. But if the affirmation is not predicable of him, the negation of the other term will be predicable of him to a greater degree than his own negation. If, then, the latter negation is predicable of him, the negation of trireme will also be predicable of him; and if this is predicable of him, the affirmation will be too. This is what follows, then, for those who hold this view.
346. And it also follows for them that it is not necessary either to affirm or to deny. For if it is true that the same thing is both a man and a not-man, evidently it will be neither a man nor a not-man; for of the two affirmations there are two negations. And if the former is taken as a single proposition composed of the two, the latter also will be a single proposition opposed to the former.
347. Again, either this is true of all things, and a thing is both white and not-white, and both being and not-being, and the same applies to other affirmations and negations; or it is not true of all but is true of some and not of others. And if not of all, the exceptions will be admitted. But if it is true of all, then either the negation will be true of everything of which the affirmation is, and the affirmation will be true of everything of which the negation is, or the negation will be true of everything of which the affirmation is, but the affirmation will not always be true of everything of which the negation is. And if the latter is true, there will be something that certainly is not, and this will be an unshakeable opinion.
And if that it is not is something certain and knowable, more known indeed will be the opposite affirmation than the negation. But if in denying something it is equally possible to affirm what is denied, it is necessary to state what is true about these things, either separately (for example, to say that a thing is white and that it is not-white), or not. And if it is not true to affirm them separately, then an opponent will not be saying what he professes to say, and nothing will exist. But how could non-existent things speak or walk, as he does? Again, [according to this view] all things will be one, as has been said before (336:C 616), and man and God and a trireme and their contradictories will be the same. Similarly, if this is true of each thing, one thing will differ in no respect from another; for if it differs, this difference will be something true and proper to it. And similarly if it is possible for each to be true separately, the results described will follow. And to this we may add that all will speak the truth and all speak falsely; and that each man will admit of himself that he is in error. And at the same time it is evident that up to this point the discussion is about nothing at all, because our opponent says nothing. For he does not say that a thing is so or is not so, but that it is both so and not so; and again he denies both of these and says that it is neither so nor not so. For if this were not the case there would already be some definite statement. Further, if when the affirmation is true the negation is false, and if when the negation is true the affirmation is false, it will be impossible both to affirm and to deny the same thing truly at the same time. But perhaps someone will say that this was the contention from the very beginning.
COMMENTARY
636. Then he gives a third argument, which involves oneness and difference. The argument runs thus: if an affirmation and a negation are true of the same subject at the same time, all things will be one. But the consequent is false. Hence the antecedent must be false. In regard to this argument he does three things.
First (343:C 636), he lays down a conditional proposition and gives an example, namely, that if contradictories are true of the same subject at the same time, it will follow that the same thing will be a trireme (i.e., a ship with three banks of oars), a wall and a man.
637. And this is what (344).
Then he shows that the same impossible conclusion follows with regard to two other positions. He does this, first, with regard to the opinion of Protagoras, who said that whatever seems so to anyone is wholly true for him; for if it seems to someone that a man is not a trireme, then he will not be a trireme; and if it seems to someone else that a man is a trireme, he will be a trireme; and thus contradictories will be true.
638. Second, he does this with regard to the opinion of Anaxagoras, who said that all things exist together, so that nothing which is truly one is distinguished from other things, but all are one in a kind of mixture. For he said that everything is found in everything else, as has been shown in Book I of the Physics. This is the position which Anaxagoras adopted because he seems to be speaking about indeterminate being, i.e., what has not been made actually determinate. And while he thought he was speaking about complete being, he was speaking about potential being, as will become clear below (355:C 667). But the indeterminate is what exists potentially and is not “complete,” i.e., actual; for potency is made determinate only by actuality.
639. But the affirmation (345).
Third, he proves that the first conditional proposition is true. He does this, first, on the grounds that all things would have to be affirmed to be one; and second (346:C 640), on the grounds that affirmations would not be distinguished from their negations from the viewpoint of truth and falsity (“And it also follows”).
He accordingly says, first (345), that the first conditional proposition must be admitted by them inasmuch as they hold than an affirmation and a negation are true of the same subject at the same time because an affirmation and a negation are true of anything at all. For it is clear that the negation of some other thing seems to be predicable of each thing to a greater degree than its own negation. For it would be absurd if some subject should have its own negation predicated of it and not the negation of something else by which it is signified that this other thing is not predicable of it. For example, if it is true to say that a man is not a man, it is much truer to say that a man is not a trireme. Hence it is clear that anything of which a negation must be predicated must also have an affirmation predicated of it. Therefore a negation will be predicated of it since an affirmation and a negation are true at the same time; or if an affirmation is not predicated of it, the negation of the other term will be predicated of it to a greater degree than its own negation. For example, if the term trireme is not predicable of man, non-trireme will be predicated of him inasmuch as it may be said that a man is not a trireme. But if the affirmation is predicable, so also must the negation be, since they are verified of the same thing. A man, then, must be a trireme, and he must also be anything else on the same grounds. Hence all things must be one. Therefore this is what follows for those who maintain the position that contradictories are true of the same subject.
640. And it also follows (346).
He now draws the other impossible conclusion which follows from this view, namely, that a negation will not be distinguished from an affirmation as regards falsity, but each will be false. Thus he says that not only the foregoing impossible conclusions follow from the above-mentioned position, but also the conclusion that it is not necessary “either to affirm or to deny,” i.e., it is not necessary that either the affirmation or the negation of a thing should be true, but each may be false; and so there will be no difference between being true and being false. He’ proves this as follows.
641. If it is true that something is both a man and a not-man, it is also true that it is neither a man nor a not-man. This is evident. For of these two terms, man and not-man, there are two negations, not man and not not-man. And if one proposition were formed from the first two, for example, if one were to say that Socrates is neither a man nor a not-man, it would follow that neither the affirmation nor the negation is true but that both are false.
642. Again, either this (347).
Then he gives a fourth argument, and this is based on certitude in knowing. It runs thus. If an affirmation and a negation are true at the same time, either this is true of all things, or it is true of some and not of others. But if it is not true of all, then those of which it is true will be “admitted”; i.e., they will be conceded simply and absolutely, or according to another translation “they will be certain,” i.e., true with certainty; that is, in their case the negation will be true because the affirmation is false, or the reverse.
643. But if it is true in all cases that contradictories are verified of the same subject, this might happen in two ways. In one way anything of which affirmations are true, negations are true, and the reverse. In another way anything of which affirmations are true, negations are true, but not the reverse.
644. And if the second is true, this impossible conclusion will follow: there will be something that firmly or certainly is not; and so there will be an unshakeable opinion regarding a negative proposition. And this will be the case because a negation is always true since whenever an affirmation is true its negation is also true. But an affirmation will not always be true, because it was posited that an affirmation is not true of anything at all of which a negation is true; and thus a negation will be more certain and knowable than an affirmation. But this seems to be false because, even though non-being is certain and knowable, an affirmation will always be more certain than its opposite negation; for the truth of a negation always depends on that of some affirmation. Hence a negative conclusion can be drawn only if there is some kind of affirmation in the premises. But an affirmative conclusion can never be drawn from negative premises.
645. Now if one were to speak in the first way and say that of anything of which an affirmation is true the negation is also true, and similarly that of anything of which the negation is true the affirmation is also true, inasmuch as affirmation and negation are interchangeable, this might happen in two ways. For if an affirmation and a negation are both true at the same time, either it will be possible to state what is true of each separately, for example, to say that each of these propositions is true separately—“Man is white” and “Man is not white”; or it will not be possible to state that each is true separately but only both together. For example, if we were to say that this copulative proposition is true —“Man is white and man is not white.”
646. And if we were to speak in the second way and say that neither one is true separately but only both together, two impossible conclusions would then follow. The first is that “an opponent will not be saying what he professes to say,” i.e., he will assert neither the affirmation nor the negation of something, and “neither will exist,” i.e., both will be false; or according to another text, “nothing will exist,” i.e., it will follow that nothing is true, neither the affirmation nor the negation. And if nothing is true it will be impossible to understand or to express anything. For how can anyone understand or express non-being? Implied is the reply: in no way.
647. The second impossible conclusion would be that all things are one, as has been stated in a previous argument (345:C 639). For it would follow that a man and God and a trireme, and also their contradictories, a notman, not-God and not-trireme, are the same. Thus it is clear that, if an affirmation and a negation are true of any subject at the same time, one thing will not differ from another. For if one were to differ from another, something would have to be predicated of the one which is not predicated of the other; and so it would follow that something is definitely and properly true of this thing which does not fit the other. Therefore an affirmation and a negation will not be true of anything whatever. But it is clear that things which differ in no way are one. Thus it would follow that all things are one.
648. But if one were to speak in the first way and say that it is possible for an affirmation and a negation to be true, not only together but also separately, four impossible conclusions will follow. The first is that this position “indicates that this statement is true”; i.e., it proves that the statement just made is true. Hence another text reads, “the results described will follow,” i.e., all things will be one, because it will then be possible both to affirm and to deny each thing, and one will not differ from the other.
649. A second impossible conclusion is that all will speak the truth, because anyone at all must make either an affirmation or a negation, and each will be true. And each man will also admit of himself that he is wrong when he says that the affirmation is true; for, since he says that the negation is true, he admits that he was in error when he made the affirmation.
650. A third impossible conclusion is that up to this point there obviously could not be any investigation or dispute. For it is impossible to carry on a dispute with someone who admits nothing, because such a person really says nothing since he does not say absolutely that something is so or is not so; but he says that it is both so and not so. And again he denies both of these, for he says that it is neither so nor not so, as is evident from the preceding argument. For if he does not deny all of these he will know that something is definitely true, and this is contrary to his original position. Or according to another translation which expresses this more clearly, “there would already be some definite statement.”
651. A fourth impossible conclusion will follow because of the definition of the true and the false. For truth exists when one says that what is, is, or that what is not, is not. But falsity exists when one says that what is, is not, or that what is not, is. Hence from the definition of the true and the false it is clear that, when an affirmation is true, its negation is false; for one then says that what is, is not. And when a negation is true, its affirmation is false; for what is not is then said to be. Therefore it is impossible both to affirm and to deny the same thing truly. But perhaps an opponent could say that this last argument is begging the questiofi; for he who claims that contradictories are true at the same time does not accept this definition of the false: the false is to say that what is not, is, or that what is, is not.
LESSON 9
Three Further Arguments Against Those Who Deny the First Principle
ARISTOTLE’S TEXT Chapters 4 & 5: 1008b 2-1009a 16
348. Again, how is that man wrong who judges that a thing is so or is not so, and is he right who judges both? For if the second is right, what will his statement mean except that such is the nature of beings? And if he is not right, he is more right than the one who holds the first view, and beings will already be of a certain nature, and this will be true and not at the same time not true. But if all men are equally right and wrong, anyone who holds this view can neither mean nor state anything; for he will both affirm and not affirm these things at the same time. And if he makes no judgment but equally thinks and does not think, in what respect will he differ from plants?
349. It is most evident, then, that no one, either among those who profess this theory or any others, is really of this mind. For why does a man walk home 1 and not remain where he is when he thinks he is going there? He does not at dawn walk directly into a well or into a brook if he happens on such; but he seems to be afraid of doing so because he does not think that to fall in is equally good and not good. Therefore he judges that the one is better and the other not. And if this is so in the case of what is good and what is not good, it must also be so in the case of other things. Thus he must judge that one thing is a man and another not a man, and that one thing is sweet and another not sweet. For when he thinks that it is better to drink water and to see a man and then seeks these things, he does not make the same judgment about all of them, though this would be necessary if the same thing were equally a man and not a man. But according to what has been said there is no one who does not seem to fear some things and not others. Hence, as it appears, all men make an unqualified judgment, and if not about all things, still about what is better or worse.
350. And if they do not have science but opinion, they ought to care all the more about the truth, just as one who is ill ought to care more about health than one who is well. For one who has opinion in contrast to one who has science is not healthily disposed towards the truth.
351. Further, even if all things are so and not so as much as you like, still difference of degree belongs to the nature of beings. For we should not say that two and three are equally even; and he who thinks that four is five is not equally as wrong as he who thinks that it is a thousand. Therefore, if they are not equally wrong, obviously one is less wrong and so more right. Hence, if what is truer is nearer to what is true, there must be some truth to which the truer is nearer. And even if there is not, still there is already something truer and more certain, and we shall be freed from that intemperate theory which prevents us from determining anything in our mind.
Chapter 5
352. The doctrine of Protagoras proceeds from the same opinion, and both of these views must be alike either true or not true. For if all things which seem or appear are true, everything must be at once true and false. For many men have opinions which are contrary to one another, and they think that those who do not have the same opinions as themselves are wrong. Consequently the same thing must both be and not be. And if this is so, it is necessary to think that all opinions are true; for those who are wrong and those who are right entertain opposite opinions. If, then beings are such, all men will speak the truth. Hence it is evident that both contraries proceed from the same way of thinking.
COMMENTARY
652. Here he gives a fifth argument, which is based on the notion of truth, and it runs as follows. It has been stated that both the affirmation and the negation of something are held to be true at the same time. Therefore he who judges or thinks that “a thing is so,” i.e., that the affirmation alone is true, “or is not so,” i.e., that the negation alone is true, is wrong; and he who judges that both are true at the same time is right. Hence, since truth exists when something is such in reality as it is in thought, or as it is expressed in words, it follows that what a man expresses will be something definite in reality; i.e., the nature of beings will be such as it is described to be; so that it will not be at once the subject both of an affirmation and of a negation. Or according to another text, “beings will already be of a certain nature,” as if to say that since the statement is definitely true, it follows that a thing has such a nature. However, if one were to say that it is not he who judges that an affirmation and a negation are true at the same time that has a true opinion, but rather he who thinks that either the affirmation alone is true or the negation alone is true, it is evident that beings will already exist in some determinate way. Hence another translation says more clearly, “and in a sense this will be definitely true and not at the same time not true,” because either the affirmation alone is true or the negation alone is true.
653. But if all of those just mentioned, i.e., both those who affirm both parts of a contradiction and those who affirm one of the two, “are wrong,” and all are also right, it will be impossible to carry on a dispute with anyone who maintains this, or even to say anything that might provoke a dispute with him. Or according to another text, “such a man will not affirm or assert anything.” For, as another translation says, “he cannot assert or affirm anything of this kind,” because he equally affirms and denies anything at all. And if this man takes nothing to be definitely true, and similarly thinks and does not think, just as he similarly affirms and denies something in speech, he seems to differ in no way from plants; because even brute animals have certain definite conceptions. Another text reads, “from those disposed by nature,” and this means that such a one who admits nothing does not differ in what he is actually thinking from those who are naturally disposed to think but are not yet actually thinking. For those who are naturally disposed to think about any question do not affirm either part of it, and similarly neither do the others.
654. It is most evident (349).
Then he gives a sixth argument, which is based on desire and aversion. In regard to this he does two things. First, he gives the argument. Second (350:C 658), he rejects an answer which is a quibble (“And if they”).
He accordingly says, first (349), that it is evident that no man is of such a mind as to think that both an affirmation and a negation can be verified of the same subject at the same time. Neither those who maintain this position nor any of the others can think in this way. For if to go home were the same as not to go home, why would someone go home rather than remain where he is, if he were of the opinion that to remain where he is is the same as to go home? Therefore, from the fact that someone goes home and does not remain where he is it is clear that he thinks that to go and not to go are different.
655. Similarly, if someone walks along a path which happens to lead directly to a well or a brook, he does not proceed straight along that path but seems to fear that he will fall into the well or brook. This happens because he judges that to fall into a well or a brook is not equally good and not good, but he judges absolutely that it is not good. However, if he were to judge that it is both good and not good, he would not avoid the above act any more than he would desire it. Therefore, since he avoids doing this and does not desire it, obviously he judges or thinks that the one course is better, namely, not to fall into the well, because he knows that it is better.
656. And if this is true of what is good and what is not good, the same thing must apply in other cases, so that clearly one judges that one thing is a man and another not a man, and that one thing is sweet and another not sweet. This is evident from the fact that he does not seek all things to the same degree or make the same judgment about them, since he judges that it is better to drink water which is sweet than to drink that which is not sweet; and that it is better to see a man than to see something which is not a man. And from this difference in opinion it follows that he definitely desires the one and not the other; for he would have to desire both equally, i.e., both the sweet and the not-sweet, and both man and not-man, if he thought that contradictories were the same. But, as has been said before (349:C 655), there is no one who does not seem to avoid the one and not the other. So by the very fact that a man is differently disposed to various things inasmuch as he avoids some and desires others, he must not think that the same thing both is and is not.
657. It is evident, then that all men think that truth consists in affirmation alone or in negation alone and not in both at the same time. And if they do not think that this applies in all cases, they at least are of the opinion that it applies in the case of things which are good or evil or of those which are better or worse; for this difference accounts for the fact that some things are desired and others are avoided.
658. And if they (350).
Then he rejects a quibble. For some one could say that men desire some things inasmuch as they are good and avoid others inasmuch as they are not good, not because they know the truth but because they are of the opinion that the same thing is not both good and not good, although this amounts to the same thing in reality. But if it is true that men do not have science but opinion, they ought to care all the more about learning the truth. This is made clear as follows: one who is ill cares more about health than one who is well. But one who has an untrue opinion, in comparison with one who has scientific knowledge, is not healthily disposed towards the truth, because he is in the same state with regard to scientific knowledge as a sick man is with regard to health; for a false opinion is a lack of scientific knowledge just as illness is a lack of health. Thus it is evident that men ought to care about discovering the truth. However, this would not be the case if nothing were definitely true, but only if something were both true and not true at the same time.
659. Further, even if all (351).
Then he gives a seventh argument, which is based on the different degrees of falsity. He says that even if it should be most true that everything is so and not so, i.e., that an affirmation and its negation are true at the same time, still it is necessary that different degrees of truth should exist in reality. For obviously it is not equally true to say that two is even and that three is even; nor is it equally false to say that four is five, and that it is a thousand. For if both are equally false, it is evident that one is less false, i.e., it is less false to say that four is five than to say that it is a thousand. But what is less false is truer, or nearer to the truth, just as that is also less black which is nearer to white. Therefore it is clear that one of them speaks more truly, i.e., he comes nearer to the truth; and this is the one who says that four is five. But nothing would be closer or nearer to the truth unless there were something which is absolutely true in relation to which the nearer or closer would be truer and less false. It follows, then, that it is necessary to posit something which is unqualifiedly true, and that not all things are both true and false, because otherwise it would follow from this that contradictories are true at the same time. And even if it does not follow from the foregoing argument that there is something which is unqualifiedly true, still it has been stated already that one thing is truer and firmer or more certain than another (351:C 659); and thus affirmation and negation are not related in the same way to truth and certitude. Hence as a result of this argument and the others given above we shall be freed or liberated from this theory, i.e., from this non-mixed opinion, or one that is not tempered (and for this reason another text has “intemperate”); for an opinion is well tempered when the predicate is not repugnant to the subject. But when an opinion involves opposite notions, it is not well tempered; and the position mentioned above, which says that contradictories can be true, is an opinion of this kind.
660. Further, this position prevents us from being able to define or settle anything in our mind. For the first notion of difference is considered in affirmation and negation. Hence he who says that an affirmation and a negation are one does away with all definiteness or difference.
661. The doctrine of Protagoras (352).
Here he shows that the opinion of Protagoras is reduced to the same position as the one mentioned above. For Protagoras said that everything which seems to be true to anyone is true. And if this position is true, the first one must also be true, namely, that an affirmation and its negation are true at the same time. Hence all things must be true and false at the same time inasmuch as this follows from this position, as has been shown above (351:C 659). He proves this as follows. Many men have opinions which are contrary to one another, and they think that those who do not have the same opinions as themselves are wrong, and vice versa. If, then, whatever seems so to anyone is true, it follows that both are wrong and both are right, because the same thing is and is not. Hence according to the opinion of Protagoras it follows that both parts of a contradiction are true at the same time.
662. Similarly, if it is true that both parts of a contradiction are true at the same time, the opinion of Protagoras must be true, namely, that all things which seem true to anybody are true. For it is clear that people have different opinions, and some of these are false and others are true because they have opinions which are opposed to each other. If, then, all opposites are true at the same time (and this follows if contradictories are true at the same time), the result must be that all are right, and that what seems so to anyone is true. Thus it is clear that each position contains the same opinion, theory, or way of thinking, because one necessarily follows from the other.
LESSON 10
The Procedure Against Those Who Say that Contradictories Are True at the Same Time
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353. But the same method of discussion is not applicable in all of these cases, because some men need persuasion and others force. For the ignorance of those who have formed their opinions as a result of difficulties is easily cured, because refutation is directed not against their words but against their thought. But the cure for all of those who argue for the sake of argument consists in refuting what they express in speech and in words.
354. Those who have experienced difficulties have formed this opinion because of things observed in the sensible world, i.e., the opinion that contradictories and contraries can both be true at the same time, inasmuch as they see that contraries are generated from the same thing. Therefore, if it is impossible for nonbeing to come into being, the thing must have existed before as both contraries equally. This is Anaxagoras’ view, for he says that everything is mixed in everything else. And Democritus is of the same opinion, for he holds that the void and the full are equally present in any part, and yet one of these is non-being and the other being.
355. Concerning those who base their opinions on these grounds, then, we say that in one sense they speak the truth, and that in another they do not know what they are saying. For being has two meanings, so that in one sense a thing can come to be from non-being and in another sense it cannot. Hence the same thing can both be and not be at the same time, but not in the same respect; for while the same thing can be potentially two contraries at the same time, it cannot in complete actuality.
356. Further, we shall expect them to believe that among beings there is also another kind of substance to which neither motion nor generation nor corruption belongs in any way.
COMMENTARY
663. Having raised arguments against those who deny the first principle, and having settled the issue, here the Philosopher indicates how one must proceed differently against various men who adopted different versions of the above-mentioned error. This is divided into two parts.
In the first (353:C 663) he shows that one must proceed differently against different men. In the second (354:C 665) he begins to proceed in a different way than he did above (“Those who”).
He accordingly says, first (353), that the same method “of discussion,” i.e., of popular address (or “of good grammatical construction,” according to another translation, or of well ordered argument “or intercession,” as is said in the Greek, i.e., of persuasion) is not applicable to all of the foregoing positions; that is, to the position that contradictories can be true, and to the position that truth consists in appearances. For some thinkers adopt the foregoing positions for two reasons. Some do so because of some difficulty; for since certain sophistical arguments occur to them, from which the foregoing positions seem to follow, and they do not know how to solve them, they accept the conclusion. Hence their ignorance is easily cured. For one must not oppose them or attack the arguments which they give, but must appeal to their thought, clearing up the mental difficulties which have led them to form such opinions; and then they will give up these positions.
664. Others adopt the foregoing positions, not because of any difficulty which leads them to such positions, but only because they want to argue “for the sake of argument,” i.e., because of a certain insolence, inasmuch as they want to maintain impossible theories of this kind for their own sake since the contrary of these cannot be demonstrated. The cure for these men is the refutation or rejection “of what they express in speech and in words,” i.e., on the grounds that the word in a statement has some meaning. Now the meaning of a statement depends on the meaning of the words, so that it is necessary to return to the principle that words signify something. This is the principle which the Philosopher used above (332:C 611).
665. Those who (354).
Since the Philosopher met the difficulties above on this point by considering the meaning of words, he begins here to meet those who are in difficulties by solving their problems.
First (354), he deals with those who held that contradictories are true at the same time; and second (357:C 669), he deals with those who held that everything which appears so is true (“And similarly”).
In regard to the first he does two things. First, he sets forth the difficulty which led some men to admit that contradictories are true at the same time. Second (355:C 667), he clears up this difficulty (“Concerning those”).
He says, then, that the opinion on this point, that the parts of a contradiction may be true at the same time, was formed by some men as a result of a difficulty which arose with regard to sensible things, in which generation and corruption and motion are apparent. For it seemed that contraries were generated from the same thing; for example, air, which is warm, and earth, which is cold, both come from water. But everything which is generated comes from something that existed before; for non-being cannot come into being, since nothing comes from nothing. A thing therefore had to have in itself contradictories simultaneously, because if both the hot and the cold are generated from one and the same thing, then it turns out to be hot and not-hot itself.
666. It was because of such reasoning that Anaxagoras claimed that everything is mixed in everything else. For from the fact that anything at A seemed to come from anything else he thought that one thing could come from another only if it already existed in it. Democritus also seems to have agreed with this theory, for he claimed that the void and the full are combined in any part of a body. And these are like being and non-being, because the full has the character of being and the void the character of non-being.
667. Concerning those (355).
Here he solves the foregoing difficulty in two ways. First, he says that the opinion of those who have adopted the foregoing absurd views because of some difficulty must be met by appealing to their thought, as has been stated (353:C 663). Therefore “concerning those who base their opinions,” i.e., those who think that contradictories are true at the same time, “on these grounds,” i.e., on the reasoning mentioned above, we say that in one sense they speak the truth and in another they do not know what they are saying since their statements are absurd. For being has two meanings: actual being and potential being; and therefore when they say that being does not come from non-being, in one sense they are right and in another they are not. For being does not come from actual being but from potential being. Hence in one sense the same thing can be at the same time both being and non-being, and in another sense it cannot; for the same thing can be contraries potentially, but it cannot be both “in complete actuality,” i.e., actually. For if something warm is potentially both hot and cold, it still cannot be actually both.
668. Further, we shall (356).
Then he gives the second solution. He says that we deem it fitting that they should accept or think that there is some kind of substance to which neither motion nor generation nor corruption belongs, as is proved in Book VIII of the Physics. Now one could not conclude to the existence of this kind of substance by reason of what has been said above, namely, that contraries belong to it, because nothing is generated from them. This solution seems to be like the one reached by the Platonists, who, because of the changeable character of sensible things, were compelled to posit unchangeable separate Forms (i.e., those of which definitions are given, and demonstrations made, and certain knowledge is had) on the grounds that there could be no certain knowledge of sensible things because of their changeableness and the mixture of contrariety which they contain. But the first solution is a better one.
LESSON 11
The Reason Why Some Considered Appearances to Be True
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357. And similarly the theory that truth consists in appearances comes to some thinkers from sensible things. For they think that the truth should not be judged by the large or small number who uphold some view; and they point out that the same thing appears to be sweet to some when they taste it and bitter to others. Hence, if all men were ill or all were mad, and only two or three were healthy or in possession of their wits, the latter would appear ill or mad and not the former. Further, they say that the impressions made upon many of the other animals are contrary to those made upon us, and that to the senses of each person things do not always appear to be the same. Therefore it is not always evident which of these views is true or which is false, but both appear equally so. And it is for this reason that Democritus says that either nothing is true or it is not evident to us.
COMMENTARY
669. Having solved the difficulty which led the ancient philosophers to maintain that contradictories are true at the same time, the Philosopher now dispels the difficulty which led some thinkers to maintain that every appearance is true.
This part is divided into two. First (351:C 669), he gives the difficulties which led some thinkers to hold the position mentioned above. Second (363:C 685), he dispels these difficulties (“But in reply”).
In regard to the first he does two things. First, he gives the reason which led these men to maintain that every appearance is true. Second (358:C 672), he explains why they reasoned in this way (“In general”).
He therefore says, first (357), that, just as the opinion which maintained that contradictories are true at the same time came from certain sensible things in which it happens that contradictories come from the same thing, so too “the theory that truth consists in appearances,” or the opinion about the truth of appearances, is derived from certain sensible things; that is, by those who are not perverse but are drawn into this position because of difficulties. This occurs because they find that different men hold contrary opinions about the same sensible things; and they give three reasons in support of their position. First, they point out that the same thing appears to taste sweet to some atid bitter to others, so that men have contrary opinions about all sensible things. Second, they note that many animals make judgments about sensible things which are contrary to ours; for what seems tasty to the ox or to the ass is judged by man to be unpalatable. Third, they say that the same man at different times makes different judgments about sensible things; for what now appears to be sweet and palatable to him at another time seems bitter or tasteless.
670. And no certain reason can be given that clearly indicates which of these opinions is true or which is false, because one of these seems no truer to one person than the other does to another person. Therefore they must be equally true or equally false. Hence Democritus said that either nothing is definitely true or, if anything is true, it is not evident to us; for even though we acquire our knowledge of things through the senses, their judgment is not certain since they do not always judge in the same way. Hence we do not seem to have any certainty regarding the truth so that we can say that this opinion is definitely true and its contrary definitely false.
671. But someone could say, in opposing this position, that some rule can be adopted whereby a person can discern among contrary opinions the one that is true. That is, we might say that the judgment which healthy people make about sensible things is right, and the one which sick people make is not; and that the judgment which wise and intelligent people make in matters of truth is right, and the one which foolish or ignorant people make is not. He rejects this reply at the very start on the grounds that no certain judgment about the truth of any theory can be fittingly based on the number, large or small, of persons who hold it, according to which that would be said to be true which seems so to many, and that to be false which seems so to a few; for sometimes what many believe is not simply true. Now health and sickness or wisdom and foolishness do not seem to diff er only by reason of the greater or smaller number of people involved. For if all or most persons were like those who are now thought to be ignorant or foolish, they would be considered wise, and those who are now thought to be wise would be considered foolish. The same applies in the case of health and sickness. Hence the judgment regarding truth and falsity of one who is healthy and wise is no more credible than the judgment of one who is ill and foolish.
LESSON 12
Two Reasons Why Some Identify Truth with Appearances
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358. And in general it is because these philosophers think that discretion is sensory perception, and that this in turn is alteration, that they say that what appears to the senses is necessarily true.
359. For it is for these reasons that both Empedocles and Democritus and, we may probably say, every one of the other philosophers became involved in such opinions. For Empedocles also says that when men change their condition they change their knowledge, “for understanding varies in men in relation to what is seen,” according to him. And elsewhere he says, “Insofar as they are changed into a different nature, to that extent it is proper for them always to think other thoughts.” And Parmenides also speaks in the same way: “For just as each has his mixture of many-jointed limbs, so intellect is present in men; for it is the same thing, the nature of the limbs, which exercises discretion in men—in all and in each; for that which is more is intellect.” Anaxagoras is also recorded as saying to some of his companions that things were such to them as they thought them to be. And men also say that Homer maintained this view, because he made Hector, after he was stunned by the blow, think other thoughts; implying that people of sound and unsound mind both think but not the same thoughts. It is evident, then, that if both of these states of mind are forms of knowledge, beings must also be so and not so at the same time.
360. Hence their conclusion happens to be the most serious one. For if those who have seen most clearly the truth which it is possible for us to have (and these are those who seek and love it most), maintain such opinions and express such views about the truth, how is it unfitting that those who are trying to philosophize should abandon the attempt? For to seek the truth will be like chasing birds.
361. Now the reason these men held this opinion is that, while they investigated the truth about beings, they thought that sensible things alone exist; and in these much of the nature of the indeterminate, i.e., the kind of being which we have described (355), is present. Hence, while they speak in a plausible way, they do not say what is true; for it is more plausible to speak as they do than as Epicharmus did to Xenophanes.
362. Again, since they saw that the whole of the natural world is in motion, and that we can say nothing true about what is undergoing change, they came to the conclusion that it is impossible to say anything true about what is always changing altogether. For it was from this view that the most extreme of the opinions mentioned above blossomed forth; that is, the opinion held by those who are said to Heraclitize, and such as Cratylus expressed, who finally thought that he should say nothing but only moved his finger, and criticized Heraclitus for saying that it is impossible to step into the same river twice; for he himself thought that this could not be done even once.
COMMENTARY
672. He gives the reason why these philosophers adopted the foregoing position. First (358:C 672), he shows how sensory perception provided one reason for adopting this position; and second (361:C 681), how sensible objects provided another (“Now the reason”).
In regard to the first part he does three things. First, he explains how sensory perception provided one reason for adopting this position. Second (359:C 674), he recounts the opinions of different men which have this reason as their common basis (“For it is”). Third (36o:C 680), he attacks these opinions (“Hence their conclusion”).
He accordingly says, first (158), that the ancients were of the opinion that discretion, i.e., wisdom or science, is merely sensory perception; for they did not make any distinction between sense and intellect. Now sensory perception comes about through a certain alteration of a sense with reference to sensible objects. And so the fact that a sense perceives something results from the impression which a sensible thing makes on the sense. Thus a sensory perception always corresponds to the nature of the sensible object as it appears. Hence, according to these thinkers, whatever appears to the senses is necessarily true; and since we must add that all knowing is sensory, it follows that whatever appears in any way at all to anyone is true.,
673. But this argument fails, not only because it holds that sense and intellect are the same, but also because it maintains that the judgment which a sense makes about sensible objects is never false. For while a sense may make a mistake about common and accidental sensible objects, it does not do this with regard to its proper sensible object, except perhaps when the sensory organ is indisposed. And even though a sense is altered by its sensible object, the judgment of a sense does not have to conform to the conditions of the sensible object; for it is not necessary that the action of an agent be received in the patient according to the mode of being of the agent but only according to that of the patient or subject. This is why a sense sometimes is not disposed to receive the form of a sensible object according to the mode of being which the form has in the sensible object, and it therefore sometimes judges a thing to be otherwise than it really is.
674. For it is (359).
He presents the opinions which different men held for the reasons stated above. Now all of the statements of these men which he adduces imply two things: first, that intellect is the same as sense, and, second, that every appearance is true. Thus he says that it is for the reasons mentioned above that Empedocles and Democritus and each of the other philosophers became involved in such opinions about reality “we may probably say,” i.e., we can conjecture on the basis of their statements.
675. For Empedocles said that those who change “their condition,” i.e., some bodily disposition, also change their understanding; implying that the intellect, to which knowledge belongs, depends on a condition of the body, just as a sense does. For understanding increases in men “in relation to what is seen”; that is, an increase in knowledge takes place in a man by reason of the fact that something new begins to appear to him, and this comes about as a result of some change in a bodily disposition. Another translation states this more clearly, saying, “For purpose or decision develops in man in relation to what is at hand”; as if to say, according to the different dispositions which are actually present in men, new decisions or new purposes or new judgmerits develop in them. And the implication is that decision or purpose does not, depend on any intellective power in man over and above the senses but only on a disposition of the body, which is changed with the presence of different things. But in other works ‘ of his Empedocles says that, to the extent that alteration occurs, that is, to the extent that men are changed to another bodily disposition, to that extent, he says, there is always thoughtfulness in them; that is, thought, concern, or planning arises in them proportionately. This translation is a difficult one to understand, but another states this notion more clearly, saying, “to the extent that men have been changed, to that extent they are always determined to think other thoughts or even foolish ones.” Or according to another text, “It is proper for them [always to think other thoughts],” as if to say that, insofar as a man is changed in some bodily disposition, to that extent his basic outlook is different-implying that he has a different understanding and a different outlook.
676. Then he gives Parmenides’ opinion in this matter. He says that Parmenides speaks about the truth of things in the same way that Empedocles does, for Parmenides says ‘ that, just as each man has an arrangement of jointed members, or “of many-jointed limbs,” according to another text, so intellect is present in men; implying that there is a great deal of variety and circumvolution in the members of man in order that such an arrangement of members may be adjusted for the operation of the intellect, which depends on the way in which the members are combined, according to him. For he says that it is the same thing “which cares for,” i.e., which has the care or supervision of the members because of the nature of the members, and which is “in each,” i.e., in the individual parts of the universe, and “in all,” i.e., in the whole universe. Yet insofar as it is present in the whole universe and in its individual parts and in men, it is designated by different names. In the whole universe it is called God, in the individual parts it is called nature, and in men it is called thought. Thus it is present to a greater degree in man than it is in the other parts of the universe; for in man this power thinks as a result of the determinate way in which his members are combined, but this does not apply in the case of other things. In this statement he also wants it understood that thought is a result of the way in which the body is composed, and thus does not differ from sensory perception. Another translation states this more clearly, saying, “For it is the same thing, the nature of the limbs, which exercises discretion in men-in all and in each; for that which is more is intellect.”
677. Then he gives the opinion of Anaxagoras, who expressed it to some of his companions and friends and had them commit it to memory, namely, that things are such to them as they take or believe them to be. This is the second point which is touched on in these statements of the philosophers, namely, that truth depends on opinion.
678. Then he gives the view of Homer, who seemed to be of the same opinion according to what people said of him. For in his story he made Hector lie, as it were, in a trance from the blow which he had been dealt, “lingering in another place,” i.e., to think other thoughts than he had thought before, or, according to another text, to be of a different opinion from the one which he had before; as if in lingering and not lingering, i.e., in the state in which he lay after being struck down, he would both think and not think, although not about the same thing. For he knew those things which then appeared to him, but not those which he had known before, and had then ceased to know. Another translation expresses the idea thus: “Implying that people of sound and unsound mind both think but not the same thoughts”; as if to say that, just as this is true of Hector, who had strange opinions after the blow, so too it is possible for others to have sound and foolish opinions at the same, although not about the same things but about different ones.
679. Now from all of the foregoing views of the philosophers he draws his intended conclusion that, if both of these states of mind constitute knowledge, i.e., those states in which a man thinks contrary things when he is changed from one state to another, it follows that whatever anyone thinks is true; for knowing would not consist in thinking what is false. Hence it follows that beings are equally so and not so.
680. Hence, their conclusion (360).
Here he attacks the above-mentioned philosophers. He says that the conclusion which they drew is the most serious one. For if those who have seen the truth most clearly, insofar as it is possible for man to see it (namely, the foregoing philosophers, who are also the ones that love and seek it most of all) offer such opinions and views about the truth, how is it unfitting that these philosophers should grieve about the ineffectualness of their study if truth cannot be found? Another text reads, “How is it unfitting that those who are trying to philosophize should give up or abandon the attempt?” i.e., that a man should not cling to those who want to philosophize but despise them. For, if a man can know nothing about the truth, to seek the truth is to seek something which he cannot attain. In fact he resembles someone who chases or hunts birds; for the more he pursues them the farther they get away from him.
681. Now the reason (361).
He indicates how sensible things influenced this opinion, i.e., how they provided a basis for the above-mentioned position. For, since sensible things are naturally prior to the senses, the dispositions of the senses must depend on those of sensible things. He gives two ways in which sensible things provided a basis for this position. The second (362) is treated at the words, “Again, since they.”
He accordingly says, first, that the reason why the foregoing philosophers adopted this position is this: since they aimed to know the truth about beings, and it seemed to them that sensible things alone exist, they therefore based their doctrine about truth in general on the nature of sensible things. Now in sensible things much of the nature of the infinite or indeterminate is present, because they contain matter, which is not in itself limited to one form but is in potency to many; and in these the nature of being is also found just as we have pointed out: the being of sensible things is not determinate but is open to various determinations. It is not to be wondered at, then, if he does not assign a definite knowledge to the senses, but one kind of knowledge to one sense, and another kind to another sense.
682. And for this reason the abovementioned philosophers use the foregoing argument plausibly or fittingly, though they are not right in claiming that there is nothing definite in sensible things; for even though matter in itself is indeterminately disposed for many forms, nevertheless by a form it is, determined to one mode of being. Hence, since things are known by their form rather than by their matter, it is wrong to say that we can have no definite knowledge of them. Yet, since the opinion of these philosophers has some plausibility, it is more fitting to speak as they do than as Epicharmus did to Xenophanes, who seems to have said that all things are immovable, necessary and known with certainty.
683. Again, since they (362).
He gives the second way in which sensible things provided a basis for this opinion. He says that the philosophers saw that the whole of the natural world, i.e., the sensible world, is in motion, and they also saw that no attribute can be predicated of anything that is being changed insofar as it is being changed; for whatever is being changed insofar as it is being changed is neither white nor black. Hence, if the nature of sensible things is being changed always and “altogether,” i.e., in all respects, so that there is nothing fixed in reality, it is impossible to make any statement about them that is definitely true. Thus it follows that the truth of an opinion or proposition does not depend on some determinate mode of being in reality but rather on what appears to the knower; so that it is what appears to each individual that is true for him.
684. That such was their argument becomes clear as follows. For from this assumption or opinion there sprouted “the most serious or extreme” opinion of the philosophers of whom we have spoken, i.e., the opinion which is found to be the most serious or extreme in this class. And this is the one which he called “Heraclitizing,” i.e., following the opinion of Heraclitus, or the opinion of those who were disciples of Heraclitus, according to another text, or of those who professed to follow the opinion of Heraclitus, who claimed that all things are in motion and consequently that nothing is definitely true. This opinion also was maintained by Cratylus, who finally arrived at such a pitch of madness that he thought that he should not express anything in words, but in order to express what he wanted he would only move his finger. He did this because he believed that the truth of the thing which he wanted to express would pass away before he had finished speaking. But he could move his finger in a shorter space of time. This same Cratylus also reprimanded or rebuked Heraclitus. For Heraclitus said that a man cannot step into the same river twice, because before he steps in a second time the water of the river already has flowed by. But Cratylus thought that a man cannot step into the same river even once, because even before he steps in once the water then in the river flows by and other water replaces it. Thus a man is incapable not only of speaking twice about anything before his disposition is changed but even of speaking once.
LESSON 13
Change in Sensible Things Not Opposed to Their Truth
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363. But in reply to this theory we shall also say that there is some reason why these men should think that what is changing, when it is changing, does not exist.
364. Yet there is a problem here; for what is casting off some quality retains something of what is being cast off, and something of what is coming to be must already exist. And in general if a thing is ceasing to be, there must be something which is; and if a thing is coming to be, there must be something from which it comes to be and something by which it comes to be; and this process cannot proceed to infinity.
365. But setting aside these considerations, let us say that change in quantity and change in quality are not the same. Let it be granted, then, that a thing does not remain the same in quantity; but it is by reason of its form that we know each thing.
366. Again, those who hold this view deserve to be criticized, because what they saw in the case of a very small number of sensible things they asserted to be true also of the whole universe. For it is only that region of the sensible world about us which is always in process of generation and corruption. But this is, so to speak, not even a part of the whole, so that it would have been juster for them to have esteemed the changing because of the whole than to misjudge as they did the whole because of its changing part.
367. Further, it is evident that in answering these men we shall say the same things as we said before (356); for we must show them and make them understand that there is a kind of nature which is immobile.
368. And those who say that the same thing both is and is not at the same time can also say that all things are at rest rather than in motion. For according to this view there is nothing into which anything may be changed, since everything is already present in everything.
COMMENTARY
685. He argues against the foregoing opinions. First (363:C 685), he argues against the views that were held about the changeable character of sensible things; and second (369:C 692), against the statements that were made regarding sensory appearances (“Now concerning the truth”).
In regard to the first part (363) he gives six arguments. The first of these is as follows: he who thinks that what is not does not exist, has a true opinion and makes a true statement if he expresses this. But what is being changed, while it is being changed, is neither that to which it is being changed nor that from which it is being changed; and thus some true statement can be made about a thing that is undergoing change. Hence, in opposing the foregoing theory or “account” (i.e., the opinion that no true statement can be made about anything which is changing), we can say that there is some ground or valid reason “in their case,” i.e., according to the opinion of the foregoing philosophers, for thinking “that what is changing,” or what is being changed, “when it is changing,” i.e., while it is undergoing change, does not exist; that is, there is some reason for thinking that it has no being.
686. Yet there is (364).
Then he gives the second argument, and it runs thus: everything which is being changed already has some part of the terminus to which it is being changed, because what is being changed, while it is being changed, is partly in the terminus to which it is being changed, and partly in the terminus from which it is being changed, as is proved in Book VI of the Physics (or, according to another text, “that which is casting off some quality retains sdmething of what is being cast off”). And by this statement we are given to understand that anything which is being moved retains some part of the terminus from which it is being moved, because so long as a thing is being moved it is casting off the terminus from which it is being moved; and it is possible only to cast off some quality which belongs to a mobile subject. And something of what is coming to be must already exist, because everything which is coming to be was coming to be, as is proved in Book VI of the Physics. And it is also evident that, if something is ceasing to be, there must be something which is; for if it did not exist in any way at all, it already would have ceased to be and would not be ceasing to be. Similarly, if something is coming to be, there must be a matter from which it is coming to be and an agent by which it is coming to be. But this cannot go on to infinity, because, as is proved in Book II (153:C 301), there cannot be an infinite regress either in the case of material causes or in that of efficient causes. Hence a major problem faces those who say that no true statement can be made about anything which is being moved or generated, both because each thing which is being moved or generated has some part of the terminus to which it is being moved, and because in every process of generation or motion there must be held to be something unproduced and unchangeable both on the part of the matter and on that of the agent.
687. But setting aside (365).
Then he gives the third argument, and this rejects the very ground on which these thinkers base their opinion that all sensible things are always in motion. For they were led to make this statement because of things which increase as a result of growth. For they saw that a thing increases in quantity to a very small degree during one year, and they thought that the motion of growth was continuous, so that quantity, in which increase is observed, might be divided in proportion to the parts of time. Thus an increase in some part of quantity would take place in some part of time, and this part of quantity would be related to a whole quantity as some part of a period of time to the whole of that period. And since this kind of motion is imperceptible, they also thought that things which appear to be at rest are being moved, although by an imperceptible motion.
688. In opposing these thinkers, then, he says that, even apart from the considerations which have been made, it is clear that change in quantity and in quality or form are not the same. And although they admit that change in quantity is continuous in reality, and that all things are always being moved imperceptibly by this motion, it is not therefore necessary for this reason that all things should be being moved in quality or form. Hence it will be possible to have a definite knowledge of things, because things are known by their form rather than by their quantity.
689. Again, those who (366).
Then he gives the fourth argument. He says that “those who think in this way,’,’ i.e., those who entertain the opinion that all sensible things are always being moved because they find a small number of sensible things of which this is true, deserve to be criticized; for there are many sensible things which are capable. of being moved only from the viewpoint of local motion. For it is obvious that it is only the sensible things around us here in the sphere of active and passive things which are in process of generation and corruption. But this sphere or place amounts to nothing, so to speak, in comparison with the whole universe; for the entire earth has no sensible quantity in comparison with the outermost sphere. Hence this place is related to the universe as its central point, as the astronomers prove on the grounds that the six signs of the zodiac always appear above the earth. But this would not be the case if the earth were to hide from us some part of the heavens which are perceived by the senses. For it would be foolish to make a judgment about the whole sensible world in the light of these few things. Indeed, it would have been more acceptable if the whole sensible world had been judged according to the motion of the celestial bodies, which far surpass the others in quantity.
690. Further, it is evident (367).
He gives the fifth argument. He says that we must also use the same arguments against these men as were used above in this same book; that is, we must show them that there is a kind of nature which is immobile, namely, that of the primary mover, as is proved in Book VIII of the Physics. And this argument must be used against them, and they ought to accept it, as has been proved elsewhere (356:C 668). It is not true, then, that all things are always in motion, and that it is impossible to make any true statement about anything.
691. And those who say (368).
He gives the sixth argument. He says that their position that all things are being moved is opposed to their first position, that contradictories are true of the same subject at the same time, because if something is and is not at the same time, it follows that all things are at rest rather than in motion. For nothing is being changed in terms of any attribute which already belongs to it; for example, what is already white is not being changed as regards whiteness. But if it is possible for the same thing both to be and not be at the same time, all attributes will be present in all things, as has been proved above (345:C 639), because all will be one. Hence there will not be anything to which a thing can be changed.
LESSON 14
Seven Arguments against the View that Truth Consists in Appearances
ARISTOTLE’S TEXT Chapter 5: 1010b 1-1011a 2
369. Now concerning the truth that not everything which appears is true, the following points must be taken into consideration: first, that a sense is not false with regard to its proper object, but imagination is not the same as a sense.
370. Second, that it is surprising if some should raise the question whether continuous quantities are as great and colors really such as they appear to those who are at a distance or as they appear to those who are close at hand, and whether things are such as they appear to those who are healthy or to those who are ailing, and whether heavy things are such as they appear to those who are weak or to those who are strong, and whether those things are true which appear to those who are asleep or to those who are awake. For it is clear that they do not think so. Therefore no one who is in Lybia, having dreamed that he was in Athens, would go to the Odeon.
371. Again, concerning future things, as Plato says, the opinion of a physician and that of a person who is ignorant of the art of medicine are not of equal value as to whether someone will get well or not.
372. Again, in the case of the senses the perception of a foreign object and that of a proper object, or that of a kindred object and that of the object of the sense concerned, are not of equal value. In the case of colors it is sight and not taste which passes judgment; and in the case of flavors it is taste and not sight which does this.
373. And no one of these senses ever affirms at the same time about the same subject that it is simultaneously both so and not so. Nor at another time does it experience any difficulty about a modification, but only about the object of which the modification is an accident. I mean, for example, that the same wine, either as a result of a change in itself or in the body, might seem at one time sweet and at another not, But sweetness, such as it is when it exists, has never changed; but one is always right about it, and sweetness itself is necessarily such as it is.
374. Yet all these theories destroy this, for just as things will have no substance, neither will they have any necessity; for that is necessary which cannot be in one way and in another. Hence, if anything is necessary, it will not be both so and not so.
375. And in general if only the sensible actually exists, there would be nothing if living things did not exist; for there would be no senses. Therefore the position that neither sensible objects nor sensory perceptions would exist is perhaps true, for these are modifications of the one sensing. But that the underlying subjects which cause perception should not exist apart from perception is impossible; for a perceptioii is not the perception of itself, but there is some other
thing besides the perception which must be prior to the perception. For that which causes motion is naturally prior to that which is moved, and this is no less true if they are correlative terms.
COMMENTARY
692. Here he begins to argue dialectically against the opinion that truth if equivalent to appearances; and in regard to this he does two things. First (369:C 718), he rejects this opinion. Second (381:C 718), he draws his intended conclusion (“Let this suffice”).
In regard to the first he does two things. First, he argues dialectically against those who held this opinion because of some theory or difficulty. Second (376:C 708), he argues against those who held this opinion because of insolence (“Now there are some”).
In regard to the first part (369) he gives seven arguments. The first of these is as follows: it has been shown (367:C 690) that not all things are changeable, and “concerning the truth that not everything which appears is true,” these points must be considered. First, the proper cause of falsity is not the senses but the imagination, which is not the same as the senses. That is to say, the diversity of judgments made about sensible objects is not attributable to the senses but to the imagination, in which errors are made about sensory perceptions because of some natural obstacle. Now imagination is not the same as perception, as is proved in Book III of The Soul, but is a motion produced as a result of actual sensing. Therefore in attributing to the senses this diversity of judgments by which one person is considered to have a false perception of a particular object about which another has a true perception, they do not proceed as they should. Another translation states this better, saying, “And, first, it must be understood that a sense is not false with regard to its proper object,” implying that no sense makes a mistake about its own proper object; for example, sight is not mistaken about colors. From this it is evident that the judgment which a sense makes about its proper sensible object is a definite one, so that there must be some definite truth in the world.
693. And if someone raises the objection that error sometimes arises even with regard to proper sensibles, his answer is that this is attributable not to the senses but to the imagination; for when the imagination is subject to some sort of abnormality, it sometimes happens that the object apprehended by a sense enters the imagination in a different way than it was apprehended by the sense. This is evident, for example, in the case of madmen, in whom the organ of imagination has been injured.
694. Second, that it is (370).
Then he gives his second argument, and it runs thus: it is surprising if some “should raise the question,” or “be puzzled,” as another text says, whether continuous quantities are such as they appear to those who are at a distance or to those who are close at hand. For it is just about self-evidently true that a sense judges quantities which are close at hand to be such as they are, and those which are far away to be smaller than they are, because what seems farther away appears small, as is proved in the science of optics.
695. The same thing applies if someone raises the question whether colors are such as they appear to those who are close at hand; for it is evident that the farther an agent’s power is extended when it acts, the more imperfect is its effect; for fire heats those things which are far away to a lesser degree than those which are close at hand. And for the same reason the color of a perfect sensible body does not change that part of the transparent medium which is far away from it as completely as it changes that part which is close to it. Hence the judgment of a sense is truer about sensible colors in things close at hand than it is about those in things far away.
696. The same thing is also true if someone asks whether things are such as they appear to those who are healthy or “to those who are ailing,” i.e., those who are ill. For healthy people have sensory organs which are well disposed, and therefore the forms of sensible things are received in them just as they are; and for this reason the judgment which healthy people make about sensible objects is a true one. But the organs of sick people are not properly disposed, and therefore they are not changed as they should be by sensible objects. Hence their judgment about such objects is not a true one. This is clear with regard to the sense of taste; for when the organ of taste in sick people has been rendered inoperative as a result of the humors being destroyed, things which have a good taste seem tasteless to them.
697. The same thing also applies regarding the question whether things having weight are as heavy as they seem to those who are weak or to those who are strong; for it is clear that the strong judge about heavy things as they really arc. But this is not the case with the weak, who find it difficult to lift a weight not only because of the heaviness of it (and this sometimes happens even with the strong) but also because of the weakness of their power, so that even less heavy things appear heavy to them.
698. The same thing again applies if the question is raised whether the truth is such as it appears to those who are asleep or to those who are awake. For the senses of those who are asleep are fettered, and thus their judgment about sensible things cannot be free like the judgment of those who are awake and whose senses are unfettered. For it has been pointed out above that it would be surprising if they should be perplexed, because it appears from their actions that they are not perplexed, and that they do not think that all of the above-mentioned judgments are equally true. For if someone in Lybia seems in his dreams to be in Athens, or if someone in Paris seems in his dreams to be in Hungary, he does not when he awakens act in the same way that he would if he were to perceive this when he is awake. For, if he were awake in Athens, he would go to the Odeon, i.e., a building in Athens; but he would not do this if he had merely dreamed it. It is clear, then, that he does not think that what appears to him when he is asleep and what appears when he is awake are equally true.
699. We can argue in the same way with regard to the other issues mentioned above; for even though men often raise questions about these issues, they are not in their own mind perplexed about them. Hence it is clear that their reason for holding to be true everything which appears, is invalid; for they held this position because of the impossibility of deciding which of several opinions is the truer, as has been stated above (353:C 663).
700. Again, concerning future (371).
Here he gives his third argument. He says that in the case of future events, as Plato points out, the opinion of a physician and that of a person who is ignorant of the art of medicine are not “of equal value,” i.e., equally important, certain, true or acceptable, as to the future possibility of some sick person being cured or not. For, while a physician knows the cause of health, this is unknown to someone who is ignorant of the art of medicine. It is clear, then, that the opinion which some held that all opinions are equally true is a foolish one.
701. Again, in the case (372).
He gives his fourth argument, which runs thus: in the case of sensible objects the judgment which a sense makes about some sensible object foreign to it and that which it makes about its proper sensible object are not of equal “value,” i.e., equally true and acceptable; for example, sight and taste do not make the same sort of judgment about colors and flavors, but in the case of colors the judgment of sight must be accepted, “and in the case of flavors,” or savors, the judgment of taste must be accepted. Hence, if sight judges a thing to be sweet and taste judges it to be bitter, taste must be accepted rather than sight.
702. And in the same way too the judgment which a sense makes about its proper sensible object and the one which it makes about something akin to its proper object are not of equal value. Now those things which are said here to be akin to proper sensible objects are called common sensibles, for example, size, number and the like, about which a sense is deceived to a greater degree than it is about its proper sensible object, although it is deceived about them to a lesser degree than it is about the sensible objects of another sense or about things which are called accidental sensible objects. Hence it is clearly foolish to say that all judgments are equally true.
703. And no one (373).
He now gives his fifth argument. He says that no sense affirms at one instant of time that a thing is simultaneously both so and not so. For sight does not at the same moment affirm that something is white and not white or that it is two cubits and not two cubits or that it is sweet and not sweet. But while a sense’s power of judging may seem at different times to form opposite judgments about the same thing, still from this judgment no difficulty ever arises about the sensible modification itself, but only about the subject of this modification. For example, if we take the same subject, wine, sometimes it appears to the sense to taste sweet and sometimes not. This happens either because of some change in the sentient body, i.e., in the organ, which is infected by bitter humors, so that whatever it tastes does not seem sweet to it, or else because of some change in the wine itself. But the sense of taste never changes its judgment without judging sweetness itself to be such as it considered it to be in the sweet thing when it judged it to be sweet; but about sweetness itself it always makes a true affirmation, and always does this in the same way. Hence, if the judgment of a sense is true, as these men claimed, it also follows that the nature of sweetness is necessarily such as it is; and thus something will be definitely true in reality. And it also follows that both an affirmation and a negation can never be true at the same time, because a sense never affirms that something is both sweet and not sweet at the same time, as has been stated.
704. Yet all these (374).
He gives the sixth argument. He says that, just as all of the above-mentioned theories or opinions destroy substantial predicates, as has been shown above (341:C 625), in a similar way they destroy all necessary predicates. For it follows that nothing could ever be predicated of anything else either substantially or necessarily. That nothing could be predicated of anything else substantially is clear from what has been stated above. That nothing could be predicated of anything else necessarily is proved as follows. That is necessary which cannot be otherwise than it is; therefore, if everything which is can exist in one way or in another way, as is held by those who say that contradictories and opposite opinions are true at the same time, it follows that nothing is necessary in the world.
705. And in general (375).
Then he gives the seventh argument. He says that, if everything which appears is true, and a thing is true only insofar as it appears to the senses, it follows that a thing exists only insofar as, it is actually being sensed. But if something exists only in this way, i.e., insofar as it is being sensed, then it follows that nothing would exist if the senses did not exist; and this would follow if there were no animals or living things. But this is impossible.
706. For this can be true, that sensibles under the aspect of their sensibility do not exist; i.e., if they are considered under the aspect of sensibles actualized, they do not exist apart from the senses, for they are sensibles actualized insofar as they are present in a sense. And according to this every actualized sensible is a certain modification of the subject sensing, although this would be impossible if there were no sensory beings. But that the sensible objects which cause this modification in a sense should not exist is impossible. This becomes clear as follows: when some subsequent thing is removed it does not follow that a prior thing is removed. But the thing producing the modification in a sense is not the perception itself, because a perception is not the perception of itself but of something else, and this must be naturally prior to the perception just as a mover is prior to the thing which is moved. For sight does not see itself but sees color.
707. And even if someone were to raise the objection that a sensible object and a sense are correlative and thus naturally simultaneous, so that when one is destroyed the other is destroyed, Aristotle’s thesis is still true; for what is potentially sensible is not said to be relative to a sense because it is referred to a sense, but because the sense is referred to it, as is stated in Book V of this work (496:C 1027)- It is dearly impossible, then, to say that some things are true because they appear to the senses; yet this is what those men maintain who claim that all appearances are true, as is evident from the foregoing statements.
LESSON 15
Refutation of the View that Contradictories Can Be Shown to Be True at the Same Time. Contraries Cannot Belong to the Same Subject at the Same Time
ARISTOTLE’S TEXT Chapter 6: 1011a 3-1011b 22
376. Now there are some, both of those who have been convinced by theories of this kind and of those who merely state them, who raise a difficulty; for they ask who it is that judges a man to be healthy, and in general who it is that judges rightly in each particular case. But such difficulties are like wondering whether we are now asleep or awake; and all such difficulties amount to the same thing. For these people think it fitting that there should be a reason for everything; for they are seeking a starting point, and they think they can get this by demonstration. Yet that sometimes they are not convinced they make evident in their actions. But according to what we have said this is characteristic of them; for they are seeking a reason for things for which no reason can be given, because the starting point of demonstration is not demonstration. These men, then, might easily believe this truth, for it is not difficult to grasp.
377. But those who seek compulsion only in words are seeking the impossible. For they deem it right to speak as they do, and immediately say contrary things.
378. Yet if not all things are relative but some things are absolute, not everything which appears will be true; for that which appears appears to someone. Thus he who says that all things which appear are true, makes all things which are, relative. Hence, those who look for compulsion in words, and think it fitting to maintain this view at the same time, must be careful to add that it is not what appears that is true, but what appears for him to whom it appears, and at the time when it appears, and in the manner in which it appears, and so on. And if they maintain their view but not in this way, it will soon happen that they are saying contrary things. For it is possible that the same thing may appear to be honey to the sense of sight but not to the sense of taste, and that, since we have two eyes, things will not appear the same to each if their sight is unequal. Now, as we have stated, there are some who say, for the reasons already given (357), that what appears is true, and that all things are therefore equally true and false, because they do not always appear the same to all men or to the same man (for they do not always happen to be the same) but often have contrary appearances at the same time. For touch says there are two objects when the fingers are crossed, but sight says there is one. And in answering these men we must say that what appears is true, but not for the same man and in the same way and at the same time, so that when these qualifications are added what appears will be true. But perhaps it is for this reason that those who argue thus, not because of some difficulty but for the sake of argument, must say that this is not true but true for this person.
379. And, as has been said before (378), they must make everything relative both to opinion and to perception, so that nothing has come to be or will come to be unless someone has first formed an opinion about it. But if something has come to be or will come to be, it is evident that not all things depend on opinion.
380. Further, if a thing is one, it is relative to one thing or to a determinate number; and if the same thing is both half and equal, still the equal is not relative to the double or the half to the equal. If, then, in relation to the thinking subject, man and the object of thought are the same, rnan will not be the thinking subject but the object of thought. And if each thing is relative to the thinking subject, the thinking subject will be relative to things infinite in species.
381. Let this suffice, then, regarding the points under discussion: that the firmest opinion of all is the one which asserts that opposite statements are not true at the same time; the conclusions that follow for those who say that they are true; and why they speak as they do.
382. But since it is impossible for contradictories to be true of the same subject at the same time, it is evident that contraries cannot belong to the same subject at the same time; for one of two contraries is a privation. But a privation is nothing less than the negation of substance from some determinate genus. Therefore, if it is impossible to affirm and deny something truly at the same time, it is also impossible for contraries to belong to the same subject at the same time; but either both belong in a certain respect, or the one in a certain respect and the other absolutely.
COMMENTARY
708. He argues against those who adopted the above-mentioned theory not because of any reason but merely because they are obstinate; and in regard to this he does two things. First (376:C 7o8), he shows how these men were moved to adopt this opinion; and second (377:C 711), how thit opinion must be dealt with (“But those who”).
He accordingly says, first (376), that, besides the foregoing thinkers who adopted the above-mentioned opinion because of certain difficulties, there are some “among those who have been persuaded to accept these views,” or opinions (i.e., those who continue to deceive themselves and have only these arguments to support their view), who raise a question. Another translation reads: “Now there are some, both of those who have been convinced by theories of this kind and of those who merely state them, who are puzzled or raise a question.” And this statement means that some of those who are puzzled, i.e., some of those who hold the above-mentioned opinion, consider only these difficulties and use the arguments which are given below. For if someone says to them that in the case of contrary opinions we should believe those persons who are healthy rather than those who are ill, and those who are wise rather than those who are ignorant, and those who are awake rather than those who are asleep, they will immediately ask how it is possible to distinguish with certainty between a healthy person and a sick one, and one who is awake and one who is asleep, and one who is wise and one who is foolish. In short, regarding all differences of opinion they will ask how it is possible to decide which one of these judges rightly in each particular case; for a man may seem to be wise to some and foolish to others, and the same applies in other cases.
709. But these questions are foolish, for they are similar to the question whether we are now asleep or awake; for the distinction between all of these is not essential. Yet all of the foregoing difficulties amount to the same thing since they have a common root. For these sophists desire that demonstrative arguments should be given for all things; for it is obvious that they wanted to take some starting point which would be for them a kind of rule whereby they could distinguish between those who are healthy and those who are ill, and between those who are awake and those who are asleep. And they were not content to know this rule in just any way at all but wanted to acquire it by demonstration. That these men were in error, then, becomes evident from their actions, according to what has been said. And from these considerations it appears that their position is false; for if the judgments of one who is asleep and of one who is awake were equally good, then the same thing would result from each judgment when men act. But this is clearly false. Another text says, “But that sometimes they are not convinced they make evident in their actions”; and this statement is the clearer one in the light of the things laid down above. For although these men maintain this view and raise such questions, still they are not deceived in their own mind so that they believe the judgment of one who is asleep and the judgment of one who is awake to be equally true. And this is clear from their actions, as has been pointed out.
710. But even though they are not deceived so as to be perplexed in this matter, this “nevertheless is characteristic of them,” i.e., this weakness of mind that they should seek a demonstrative argument for things for which no demonstration can be given. For “the starting point of demonstration is not demonstration”; i.e., there can be no demonstration of it. And this is easy for them to believe, because this too is not difficult to grasp by demonstration; for a demonstrative argument proves that not all things can be demonstrated, otherwise there would be an infinite regress.
711. But those who (377).
He now argues against the other philosophers, i.e., against those who were not moved to maintain that all appearances are true on the grounds that no rule can be established demonstratively whereby it is possible to distinguish with certainty between those who judge rightly and those who do not, but who hold the above-mentioned theory or view only because they are insolent.
In regard to this he does three things. First (377:C 711), he shows that such insolence tends to lead to an impossible conclusion. Second (378:C 712), he indicates the way in which it seems necessary to oppose them (“Yet if not all things”). Third (379:C V6), he explains how we must meet their argument from the viewpoint of truth (“And, as has been”).
He accordingly says, first (377), that those who seek “compulsion merely in words,” i.e., those who are not moved by any reason or because of the difficulty involved in some problem or because of some failure in demonstration but depend solely on words and believe that they can say anything which cannot be disproved-such people as these want to argue to an impossible conclusion. For they want to adopt the principle that contraries are true at the same time on the grounds that all appearances are true.
712. Yet if not all (378).
Then he shows how we may oppose these men by using their own position and avoid the foregoing impossible conclusion. He says that, unless everything which is, is claimed to be relative, it cannot be said that every appearance is true. For if there are some things in the world which have absolute being and are not relative to perception or to opinion, being and appearing will not be the same; for appearing implies a relation to perception or to opinion, because that which appears appears to someone; and thus whatever is not an appearance must be true. It is clear, then, that whoever says that all appearances are true, makes all beings relative, i.e., to perception or to opinion. Hence, in opposing the foregoing sophists who seek compulsion in words, we may say that, if anyone thinks it fitting “to grant this view,” i.e., to concede this opinion which they maintain, he must be careful, or observant, lest he be led to admit that contradictories are true at the same time; for it should not be said unqualifiedly that everything which appears is true, but that what appears is true for the one to whom it appears, and inasmuch as it appears, and when it appears, and in the manner in which it appears. We would be allowed to add these qualifications on the grounds that a thing does not have being in an absolute sense but only relatively.
713. Now this should be noted by those who want to adopt this position, because if someone were to grant them that every appearance is true, and thus not admit the above-mentioned qualifications, as has been stated, it would follow immediately that he is saying that contraries are true at the same time. For it is possible that the same thing may appear to be honey to the sense of sight because its color resembles that of honey, and not appear to be honey to the sense of taste because it does not taste like honey. And similarly when two eyes are unlike, the vision which is had through each is not the same, or the visual impressions which we get through each eye do not seem the same. For example, if the pupil of one eye were infected by some gross or dark vapor, and the other were free of this, all things would seem dark or obscure through the infected eye but not through the good one. I say, then, that one must be careful, or observant, because this is necessary in confronting the foregoing sophists, who say, for the reasons given above (376:C 708), that every appearance is true.
714. And from this position it would also follow that all things are equally true and false, because they do not appear the same to all men or even the same to one man, since the same man very often makes contrary judgments about the same thing at the same time on the basis of different senses; for example, sight judges that thing to be one which touch judges to be two, because when the fingers are crossed it happens that the same tangible object is sensed by different organs of touch; that is, the contact through different fingers affects the tactual power as though there were two tangible objects. But it does not seem to the same man through the same sense and in the same way and at the same time that this is true namely, that contraries are true at the same time.
715. Therefore, it is perhaps necessary to use this answer against the above-mentioned sophists who argue thus not because of some difficulty but for the sake of argument (as though upholding this statement for its own sake because they are perverse), namely, that this is not true absolutely but true for this person. For it does not follow from this that contradictories are true at the same time, because it is not contradictory that something should be true for one person and not true for another.
716. And, as has been said (379).
He tells us that we should oppose the foregoing sophists from the standpoint of the truth and not just offer an argument ad hominem, namely, not by granting the false opinion which they maintain. And he does this by means of two arguments. The first is this: as has been stated before, if everything which appears is true, they must “make all things relative,” i.e., to perception or to opinion. Now from this the untenable position follows that nothing may exist or come to be if it is not thought of in some way. But if this is false (because’ many things are and come to be of which there is neither opinion nor knowledge, for example, things which exist in the depths of the sea or in the bowels of the earth), it is evident that not all things are relative, i.e., to perception or to opinion. Hence not every appearance is true.
717. Further, if a thing (380).
He gives the second argument. He says that what is one is relative only to one thing, and not to any one thing at all but to a determinate one. For example, it is clear that the half and the equal may be the same in their subject, yet the double is not said to be relative to the equal but rather to the half; but equal is said to be relative to equal. Similarly, if man himself as a thinking subject is also the object of thought, man is not relative to the thinking subject as a thinking subject, but as the object of thought. If, then, all beings are relative to a thinking sub iect as such, it follows that what I call the thinking subject is not one, since one is relative only to one, but it is an infinite number of things in species, since an infinite number of things are related to it. But this is impossible. Hence it cannot be said that all things are said to be relative to a thinking subject, or that everything which appears so, or is thought to be so, is therefore true.
718. Let this suffice (381).
He now draws his intended conclusion, and in regard to this he does two things. First, he draws his main conclusion; and second (382:C 719), he derives a corollary from it (“But since it is impossible”).
He accordingly says, first (381), that it is clear from the above statement that the most certain of all opinions or views is the one which states that opposite statements or propositions, i.e., contradictory ones, are not true at the same time. And the impossible conclusions which face those who say that they are true at the same time, and the reason which moved them to say this, have also been explained.
719. But since it is impossible (382).
He draws the corollary. He says that, since it is impossible, from what has been said, for two contradictories to be true of the same subject at the same time, it is also evident that contraries cannot belong to the same subject; for the privative character of one of two contraries is no less evident in the case of contraries than it is in the case of other opposites, although each of two contraries is a positive reality; for it does not consist in affirmation and negation or in privation and possession. For one of them is imperfect when compared with the other, as black when compared with white, and bitter with sweet; and thus it has a kind of privation added to it. But privation is negation of substance, i.e., in some determinate subject. And it is also the deprivation of some determinate genus; for it is a negation within a genus. For not everything which does not see is said to be blind, but only that which is found in the genus of seeing things. It is clear, then, that a contrary includes privation, and that privation is a kind of negation. Hence, if it is impossible both to affirm and to deny something at the same time, it is also impossible for contraries to belong absolutely to the same subject at the same time; but either “both belong to it,” i.e., relatively, as when both are present potentially or partially, or one is present in a certain respect and the other absolutely; or one is present in many and the more important parts, and the other only in some part; for example, an Ethiopian is black absolutely and white as regards his teeth.
LESSON 16
No Intermediate between Contradictories. How Heraclitus and Anaxagoras Influenced This Position
ARISTOTLE’S TEXT Chapter 7: 1011b 23-1012a 28
383. Neither can there be an intermediate between contradictories, but of each subject it is necessary either to affirm or to deny one thing. This first becomes evident when people define what truth and falsity are; for to say that what is, is not, or that what is not, is, is false; and to say that what is, is, or that what is not, is not, is true. Hence he who affirms that something is or is not will say either what is true or what is false. But neither what is nor what is not is said to be or not to be.
384. Further, an intermediate between contradictories will be such either in the way that green is an intermediate between white and black, or as what is neither a man nor a horse is an intermediate between a man and a horse. If it is of the latter sort, there will then be no change; for change is from what is good to what is not-good, or from the latter to the former. But that this now occurs is always apparent; for change takes place only between opposites and intermediates. But if it is a true intermediate, then in this case there will be a kind of change to something white, but not from what is not-white. However, this is not now apparent.
385. Further, the mind either affirms or denies every sensible and intelligible object. This is clear from the definition, because it expresses what is true or what is false. Indeed, when the mind composes in this way by affirming or denying, it says what is true; and when it does it otherwise, it says what is false.
386. Again, there must be an intermediate in addition to all contradictories, unless one is arguing for the sake of argument. In that case one will say what is neither true nor false. And then there will be something else besides being and non-being; and therefore there will also be some kind of change besides generation and corruption.
387. Again, there will also be an intermediate in all those classes of things in which the negation of a term implies its contrary; for example, in the class of numbers there will be a number which is neither even nor odd. But this is impossible, as is evident from the definition.
388. Further, there will be an infinite regress, and there will be things which are related not only as half again as much but even more. For it will also be possible to deny the intermediate both with reference to its affirmation and to its negation; and this again will be something, for its substance is something different.
389. Again, when one answers “no” to the question whether a thing is white, he has denied nothing except that it is; and its not-being is a negation.
390. Now some men have formed this opinion in the same way that other unreasonable opinions have been formed; for when they cannot refute eristic arguments, they assent to the argument and claim that the conclusion is true. Some men hold this view, then, for this reason, and others because they seek an explanation for everything.
391. The starting point to be used against all of these people is the definition, and the definition results from the necessity of their meaning something; for the concept, of which the word is a sign, is a definition.
392. Now the statement of Heraclitus, which says that all things are and are not, seems to make all things true; and the statement of Anaxagoras that there is an intermediate between contradictories seems to make everything false; for when all things are mixed together, the mixture is neither good nor not good, so that it is impossible to say anything true.
COMMENTARY
720. Having argued dialectically against those who maintain that contradictories are true at the same time, Aristotle now argues against those who maintain that there is an intermediate between contradictories; for these thinkers do not always say that the one or the other part of a contradiction is true. In regard to this he does two things. First (383:C 720), he argues against this position. Second (393:C 736), he argues against certain other unreasonable questions which follow from this position and from the one above (“With these points”).
In regard to the first he does two things. First, he raises arguments against the position mentioned. Second (390:C 730, he gives the reason why some thinkers have been moved to hold this position (“Now some men”).
In regard to the first part he gives seven arguments. He says, first (383), that, just as contradictories cannot be true at the same time, neither can there be an intermediate between contradictories, but it is necessary either to affirm or deny one or the other.
721. This first becomes evident from the definition of truth and falsity; for to say what is false is simply to say that what is, is not, or that what is not, is. And to say what is true is simply to say that what is, is, or that what is not is not. It is clear, then, that whoever says that something is, says either what is true or what is false; and if he says what is true, it must be so, because to say what is true is to say that what is, is. And if he says what is false, it must not be so, because to say what is false is simply to say that what is, is not. The same thing applies if he says that something is not; for if he says what is false, it must be; and if he says what is true, it must not be. Therefore, either the affirmation or the negation is necessarily true. But he who holds that there is an intermediate between contradictories does not claim that it is necessary to say that what is either is or is not; nor does he claim that it is necessary to speak in this way about what is not. Thus neither he who affirms nor he who denies need say what is true or what is false.
722. Further, an intermediate (384).
He gives the second argument, which runs thus: an intermediate between any two contradictories can be understood in one way as something that participates in each of the extremes, and this is an intermediate in the same genus, as green or yellow is an intermediate between white and black; or in another way as something that is the negation of each extreme, and such an intermediate is different in genus; for example, a stone, which is neither a man nor a horse, is an intermediate between a man and a horse. Therefore, if there is an intermediate between contradictories, it will be such either in the first way or in the second.
723. If it is an intermediate in the second way, there will be no change. This becomes clear as follows: every change is from what is not-good to what is good, or from what is good to what is not-good. Hence, since change is between contraries, for example, white and black, change must take place between things which are opposed as contradictories; for black is not white, as is clear from the above statements. But according to the foregoing position there cannot be change from what is not-good to what is good, or the reverse. Hence there will be no change. Yet it always appears or seems that change proceeds from what is not-good to what is good, or the reverse. That every change of this sort would be destroyed if the foregoing position is true ‘becomes clear as follows. Change can take place only between contraries and intermediates which belong to the same genus. But there can be a change from one extreme to another only through an intermediate. Therefore, if there is an intermediate between contradictories as the negation of both, i.e., as something belonging to a different genus, it will be impossible for change to take place between an extreme and an intermediate, and therefore between one extreme and another.
724. And if it is an intermediate in the first way, so that the intermediate between contradictories belongs to the same genus by participating in both, as yellow is an intermediate between white and black, ‘this impossible conclusion follows: there will be some process of generation which terminates in white and does not come from the not-white, because change proceeds not only from one extreme to another but also from an intermediate. But it does not seem to be true that there is any process of change terminating in the white which does not proceed from the not-white. Thus it is clear that there is no way at all in which there can be an intermediate between contradictories.
725. Further, the mind (385).
He gives the third argument, which runs thus: in every one of the conceptions by which the intellect knows or understands, it either affirms or denies something. Now from the definition of truth and falsity it seems that whether one affirms or denies he must say what is true or what is false; because when the intellect composes in this way, either by affirming or denying as the matter stands in reality, it expresses what is true; but when it does it otherwise, it expresses what is false. Thus it is clear that a true statement must always be either an affirmation or a negation, because some opinion must be true, and every opinion is either an affirmation or a negation. Hence it must always be either an affirmation or a negation that is true; and thus there is no intermediate between contradictories.
726. Again, there must (386).
Then he gives the fourth argument, which runs thus: if one maintains that there must be an intermediate between contradictories, then it is necessary to say that in the case of all contradictories there must be besides the contradictories themselves something true which is an intermediate between them, unless this person is arguing “for the sake of argument,” i.e., without any real reason but only because it pleases him to speak in this way. But this cannot be true in all cases, because the true and the not-true are contradictories. Thus it would follow that there is someone who says what is neither true nor false. But the opposite of this was made clear from the definition of truth and falsity.
727. Similarly, since being and nonbeing are contradictories, it will follow that there is something besides being and non-being, and thus there will be some kind of change besides generation and corruption; for generation is a change to being, and corruption a change to non-being. Therefore there can be no intermediate between contradictories.
728. Again, there will (387).
He gives the fifth argument. He says that in some genera a negation takes the place of a contrary difference; or, according to another text, “negation supplies the contrary,” because one of two contraries, which must be in the same genus, derives its definition from negation, as is clear in the case of the even and the odd, and the just and unjust. Therefore, if there is an intermediate between affirmation and negation, there will be some intermediate between all these contraries, since they obviously depend on affirmation and negation; for example, in the case of number, there will be some number which is neither even nor odd. But this is clearly impossible in the light of the definition of the even and the odd; for the even is what can be divided into equal numbers, and the odd is what cannot. Therefore it follows that there cannot be an intermediate between affirmation and negation.
729. Further, there will (388).
He now gives the sixth argument: those who claim that there is an interinediate between an affirmation and a ncgation hold some third thing besides these two, which all posit in common, saying that there is nothing intermediMe between them. But three is related it) two “as half again as much,” i.e., in a proportion of one and a half to one. Therefore, according to the opinion of
those who hold an intermediate between an affirmation and a negation it appears at first sight that all things “will be related as half again as much,” i.e., in a proportion of one and a half to one to the things which are given, because there will be not only affirmations and negations but also intermediates. And this is not the only conclusion that follows, but it also follows that there will be many more things in infinite regression. For it is evident that everything which can be affirmed can also be denied. But if it is possible to affirm that the following three things exist: an affirmation, a negation and an intermediate, it is then also possible to deny these three. And just as a negation differs from an affirmation, in a similar way there will also be some fourth thing which differs from the three mentioned; for it will have a different substance and intelligible structure than those just mentioned, in the same way that a negation has a different substance and intelligible structure from an affirmation. And it is possible to deny these four, and the negations of these will be true; and so on to infinity. Hence there will be infinitely more things than have just been posited. This seems absurd.
730. Again, when one (389).
He gives the seventh argument, and it runs as follows: if someone were to ask whether a man or some other thing is white, the one answering him must say either “yes” or “no.” If he says “yes,” it is plain that he says that the affirmation is true; but if he does not affirm this but says “no,” it is clear that he denies this. Now the only thing which he denies is what he was asked, and the negation of this is non-being because it is negative. Therefore it follows that, when he answers this question, he must of necessity either admit the affirmative or assert the negative. Hence there is no intermediate between these two.
731. Now some men (390).
He gives the reason why some men adopt this opinion, and in regard to this he does three things. First, he shows why some men have held this opinion. Second (391:C 733), he explains how one can argue dialectically against them (“The starting point”). Third (392:C 734), he notes the philosophical views on which the foregoing opinions depend (“Now the statement”)
He accordingly says, first (390), that the foregoing opinion, like other unreasonable opinions, is adopted by certain thinkers for one of two reasons. The first is this: when some men cannot refute “eristic arguments,” i.e., disputatious or sophistical arguments, which are presented to them either by others or by themselves, they agree with the one giving the argument and assent to the conclusion, saying that what has been shown is true. And then they try to confirm this by devising other arguments.
732. The second reason why men adopt this position is that some men want to discover an argument to prove everything, and therefore whatever cannot be proved they do not want to affirm but deny. But first principles, which are the common conceptions of all men, cannot be proved. Hence these men deny them and thereby adopt unreasonable views.
733. The starting point (391).
He indicates the starting point from which one must proceed to argue against such opinions. He says that the starting point is derived from the definitions of truth and falsity, or from the definitions of other terms, as is clear from the arguments given above. For men must admit the definitions of things if they hold that words signify something; for the intelligible expression of a thing which a word signifies is a thing’s definition. But if they do not admit that all words signify something, they do not differ from plants, as has been said above (348:C 652).
734. Now the statement (392).
Here he gives the opinion on which the foregoing opinions depend. He says that these opinions stem from the position of Heraclitus, who said that all things are in motion, and therefore that they both are and are not at the same time. And since what is being moved has non-being mixed with being, it follows that everything is true.
735. And from the position of Anaxagoras it follows that there is an intermediate between contradictories; for he held that everything is mixed with everything, because everything comes from everything. But neither of the extremes can be predicated of the mixture; for example, intermediate colors are neither whiteness or blackness. Hence the mixture is neither good nor not-good, neither white nor not-white; and thus there is an intermediate between contradictories. It follows, then, that everything is false; for according to the common opinion we posit nothing but affirmation and negation. Hence, if both an affirmation and its negation are false, it follows that everything is false.
LESSON 17
Rejection of the opinions that Everything Is True and False, and that Everything Is at Rest and in Motion
ARISTOTLE’S TEXT Chapter 8: 1012a 29-1012b 31
393. With these points settled it is evident that the theories which have been expressed univocally and about all things cannot be true as some affirm them to be. Now some say that nothing is true (for they say that there is nothing to prevent all statements from being like the statement that the diagnoal of a square is commensurable with one of its sides), and others say that everything is true. These views are almost the same as that of Heraclitus; for he who says that all things are true and all false admits both views apart from his own words. Hence, if those are impossible, these also must be impossible.
394. Further, it is evident that there are contradictories which cannot be true at the same time. Nor can they all be false, though this would seem more possible from what has been said.
395. But in opposing all such views it is necessary to postulate, as has been stated in the above discussion (332), not ‘ that something is or is not, but that a word signifies something. Hence it is necessary to argue from a definition, once we have accepted what truth and falsity mean. But if to say what is true is merely to deny what is false, not everything can be false. For one part of a contradiction must be true.
396. Again, if everything must be either affirmed or denied, both cannot be false; for one part of a contradiction is false.
397. And the view commonly expressed applies to all such theories—they destroy themselves; for he who says that everything is true makes the contrary of his own statement true, and thus makes his own not true; for the contrary denies that it is true. And he who says that everything is false makes his own statement false. But if the former makes an exception of the contrary statement, saying that it alone is not true, and the latter makes an exception of his own statement, saying that it is not false, still they will have to consider the truth and falsity of an infinite number of statements. For he who says that a true statement is true is right; and this process will go on to infinity.
398. Now it is evident that those who say that all things are at rest do not speak the truth, and neither do those who say that all things are in motion.
399. For if all things are at rest, the same thing will always be true and false; btit this seems to be something that changes, for he who makes a statement at mic time was not and again will not be.
400. And if all things are in motion, nothing will be true, and so everything will be false. But it has been shown that this is impossible.
401. Further, it must be some being which is changed; for change is from something to something.
402. But it is not true that all things are at rest or in motion sometimes, and nothing always; for there is something which always moves the things that are being moved, and the first mover is itself immovable.
COMMENTARY
736. He argues dialectically against certain positions which stem from those mentioned above. First (393:C736), he argues against certain men who destroy the principles of logic; and second (398:C 744), against certain men who destroy the principles of natural philosophy (“Now it is evident”).
For first philosophy should argue dialectically against those who deny the principles of the particular sciences, because all principles are based on the principle that an affirmation and a negation are not true at the same time, and that there is no intermediate between them. Now these principles are the most specific principles of this science, since they depend on the concept of being, which is the primary subject of this branch of philosophy. But the true and the false belong specifically to the study of logic; for they depend on the kind of being which is found in the mind, with which logic deals; for truth and falsity exist in the mind, as is stated in Book VI of this work (558:C 1231). Motion and rest, on the other hand, belong properly to the study of natural philosophy, because nature is defined as a principle of motion and of rest. Now the error made about truth and falsity is a result of the error made about being and nonbeing, for truth and falsity are defined by means of being and non-being, as has been said above. For there is ‘truth when one says that what is, is, or that what is not, is not; and falsity is defined in the opposite way. And similarly the error made about rest and motion is a result of the error made about being and non-being; for what is in motion as such does not yet exist, whereas what is at rest already is. Hence, when the errors made about being and non-being have been removed, the errors made about truth and falsity and rest and motion will then also be removed.
737. Regarding the first part of this division he does two things. First (393:C 737), he gives the erroneous opinions about truth and falsity. Second (394:C 739), he criticizes these opinions (“Further, it is evident”).
Thus he says (393) that, “with these points settled,” i.e., with the foregoing points established which have to be used against the paradoxical positions mentioned above, it is obviously impossible that the views of some men should be true, namely, that we must form an opinion “univocally,” i.e., think in the same way, about all things, so that we should say that all things are equally true or equally false. For some thinkers said that nothing is true but everything false, and that there is nothing to prevent us from saying that all statements are just as false as the statement (which is false) that the diameter of a square is commensurate with one of its sides. But others have said that all things are true. Statements of the latter kind are a result of the opinion of Heraclitus, as has been pointed out (362:C 684); for he said that a thing is and is not at the same time, and from this it follows that everything is true.
738. And lest perhaps someone might say that besides these opinions there is also a third one, which states that everything is both true and false at the same time, he replies, as though meeting a tacit objection, that anyone who maintains this opinion also maintains both of the foregoing ones. Hence, if the first two opinions are impossible, the third must also be impossible.
739. Further, it is evident (394).
Then he presents arguments against the foregoing opinions, and the first of these is as follows: it is evident that there are certain contradictories which cannot be true at the same time or false at the same time, for example, the true and not-true, being and non-being. This can be better understood from what has been said. Therefore, if one of these two contradictories must be false and the other true, not all things can be true or all false.
740. But in opposing (395).
He gives the second argument. He says that in opposing “these views,” or positions, “it is necessary to postulate,” or request, not that someone should admit that something either is or is not in reality, as has been stated above (332:C 611), because this seems to be begging the question, but that he should admit that a word signifies something. Now if this is not granted, the dispute comes to an end; but if it is granted, it is then necessary to give definitions, as has already been stated above (332:C 611). Hence we must argue against these thinkers by proceeding from definitions, and in the case of the present thesis we must do this especially by considering the definition of falsity. Now if truth consists merely in affirming what it is false to deny, and vice versa, it follows that not all statements can be false, because either the affirmation or the negation of something must be true. For obviously truth consists simply in saying that what is, is, or in saying that what is not, is not; and falsity consists in saying that what is, is not, or in saying that what is not, is. Hence it is clear that it is true to say that that is of which it is false that it is not, or to say that that is not of which it is false that it is; and it is false to say that that is of which it is true that it is not, or to say that that is not of which it is true that it is. Thus from the definition of truth and falsity it is clear that not all things are false. And for the same reason it is clear that not all things are true.
741. Again, if everything (396).
Here he gives the third argument, which runs thus: it is clear from what has been said above that we must either affirm or deny something of each thing since there is no intermediate between contradictories. It is impossible, then, for everything to be false. And by the same reasoning it is proved that it is impossible for everything to be true, i.e., by reason of the fact that it is impossible both to affirm and to deny something at the same time.
742. And the view (397).
He gives the fourth argument: all of the foregoing statements, or opinions, face this unreasonable result-they destroy themselves. This is “the view commonly expressed,” i.e., a frequently heard statement made by all; and thus another text says, “It happens that it is commonly held.” He proves this view as follows: anyone who says that everything is true makes the contrary of his own opinion true. But the contrary of his own opinion is that his own opinion is not true. Therefore he who says that everything is true says that his own opinion is not true; and thus he destroys his own opinion. Similarly it is evident that he who says that everything is false also says that his own opinion is false.
743. And because someone could say that he who claims that everything is true makes an exception of the one contrary to his own statement or bars it from what holds universaily (and the same thing applies to one who says that everything is false), he therefore
rejects this answer. He says that, if the one who says that everything is true makes his own contrary opinion an exception, saying that it alone is not true, and if the one who says that everything is false makes his own opinion an exception, saying that it alone is not false, none the less it follows that they will be able “to consider,” or bring forward, an infinite number of true statements against those who hold that all are false, and an infinite number of false statements against those who hold that all are true. For granted that one opinion is true, it follows that an infinite number are true. And granted that one opinion is false, it follows that an infinite number are false. For if the position, or opinion, that Socrates is sitting is true, then the opinion that it is true that Socrates is sitting will also be true, and so on to infinity. For he who says that a true statement is true is always right; and he who says that a false statement is true is always wrong; and this can proceed to infinity.
744. Now it is (398).
He argues against those who destroy the principles of nature, i.e., motion and rest, and in regard to this he does three things.
First, he mentions the falsity of these opinions, saying that it is evident, from what has been said above, that neither the opinion which states that everything is in motion, nor the one which states that everything is at rest, is true.
745. For if all things (399).
Second, he shows that these opinions are false. First of all he shows that the opinion which holds that everything is at rest is false; for if everything were at rest,’nothing would then be changed from the state in which it sometimes is. Hence, whatever is true would always be true, and whatever is false would always be false. But this seems to be absurd; for the truth and falsity of a proposition is changeable. Nor is this to be wondered at, because the man who has an opinion or makes a statement at one time was not and now is and again will not be.
746. Second, he uses two arguments to show that the opinion which holds that all things are in motion is false. He gives the first (400) where he says, “And if all things.” It is as follows. If all things are in motion and nothing is at rest, nothing will be true in the world; for what is true already exists, but what is in motion does not yet exist. Hence everything must be false. But this is impossible, as has been shown (395:C 740).
747. Further, it must be (401).
He gives the second argument, and it runs thus: everything that is undergoing change is necessarily a being, because everything that is being changed is being changed from something to something else, and everything that is being changed in something else belongs to the subject that is undergoing change. Hence it is not necessary to say that everything in the subject undergoing change is being changed, but that there is something which remains. Hence not everything is in motion.
748. But it is not (402).
He gives the third argument, and it disposes of a false opinion which could arise from what has been said above. For, since not all things are in motion nor all at rest, someone could therefore think that all things are sometimes in motion and sometimes at rest. In disposing of this opinion he says that, it is not true that all things are sometimes in motion and sometimes at rest, for there are certain movable things which are always being moved, namely, the celestial bodies above us, and there is a mover, namely, the first, which is always immovable and ever in the same state, as has been proved in Book VIII of the Physics.