that not the least reason why our opponents predicate opposite statements of the same thing is that they start with the assumption that quantity is not constant in the case of bodies; hence they say that the same thing is and is not six feet long. But essence depends upon quality, and this is of a determinate, whereas quantity is of an indeterminate nature. Again, when the doctor orders them to adopt some article of diet, why do they adopt it? Cf. Aristot. Met.
4.4.39-42. For on their view it is no more true that a thing is bread than that it is not; and therefore it would make no difference whether they ate it or not. But as it is, they adopt a particular food as though they knew the truth about it and it were the food prescribed; yet they ought not to do so if there were no fixed and permanent nature in sensible things and everything were always in a state of motion and flux. Again, if we are always changing and never remain the same, is it any wonder that to us, as to the diseased, things never appear the same? With this section cf. Aristot. Met.
4.5.7-14.
For to the diseased, since they are not in the same physical condition as when they were well, sensible qualities do not appear to be the same; although this does not mean that the sensible things themselves partake of any change, but that they cause different, and not the same, sensations in the diseased. Doubtless the same must be true if the change which we have referred to takes place in us. If, however, we do not change but remain always the same, there must be something permanent. As for those who raise the aforesaid difficulties on dialectical grounds, With this section cf. Aristot. Met. 4.5.3, 4, Aristot.
Met. 4.6.1-3. it is not easy to find a solution which will convince them unless they grant some assumption for which they no longer require an explanation; for every argument and proof is possible only in this way. If they grant no assumption, they destroy discussion and reasoning in general. Thus there is no arguing with people of this kind; but in the case of those who are perplexed by the traditional difficulties it is easy to meet and refute the causes of their perplexity. This is evident from what has been already said. Thus from these considerations it is obvious that opposite statements cannot be true of the same thing at one time; nor can contrary statements, since every contrariety involves privation. This is clear if we reduce the formulae of contraries to their first principles. Cf.
Aristot. Met. 4.6.10, 11. Similarly no middle term can be predicated of one and the same thing of which one of the contraries is predicated. Cf. Aristot. Met. 4.7 where, however, the point which is proved is that there can be no intermediate between contradictories. If, when the subject is white, we say that it is neither white nor black, we shall be in error; for it follows that it is and is not white, because the first of the two terms in the complex statement will be true of the subject, and this is the contradictory of white. Thus we cannot be right in holding the views either of Heraclitus Cf. Aristot. Met.
11.5.8 or of Anaxagoras. Cf. Aristot. Met.
4.7.8-8.5 If we could, it would follow that contraries are predicable of the same subject; for when he Anaxagoras. What he really meant was that even the sweetest things contain some bitter particles. Cf. Anaxagoras Fr. 11 (Diels); Burnet, E.G.P. 129. says that in everything there is a part of everything, he means that nothing is sweet any more than it is bitter, and similarly with any of the other pairs of contraries; that is, if everything is present in everything not merely potentially but actually and in differentiation. Similarly all statements cannot be false, nor all true. Among many other difficulties which might be adduced as involved by this supposition there is the objection that if all statements were false, not even this proposition itself would be true; while if they were all true it would not be false to say that they are all false.
Every science inquires for certain principles and causes with respect to every knowable thing which comes within its scope This chapter corresponds to Aristot. Met. 6.1; cf. also Aristot. Met. 4.3.1-6 and ch. 4 above. It also answers the problem stated in ch. 1.2.; e.g., the sciences of medicine and physical culture do this, and so does each of the other productive and mathematical sciences. Each one of these marks out for itself some class of objects, and concerns itself with this as with something existent and real, but not qua real; it is another science distinct from these which does this. Each of the said sciences arrives in some way at the essence in a particular class of things, and then tries to prove the rest more or less exactly. Some arrive at the essence through sense-perception, and some by hypothesis; hence it is obvious from such a process of induction that there is no demonstration of the reality or essence. Now since there is a science of nature, clearly it must be different from both practical and productive science. In a productive science the source of motion is in the producer and not in the thing produced, and is either an art or some other kind of potency; and similarly in a practical science the motion is not in the thing acted upon but rather in the agent. But the science of the natural philosopher is concerned with things which contain in themselves a source of motion. From this it is clear that natural science must be neither practical nor productive, but speculative; since it must fall under one of these classes. And since every science must have some knowledge of the essence and must use it as a starting-point, we must be careful to observe how the natural philosopher should define, and how he should regard the formula of essence—whether in the same way as the term "snub," or rather as the term "concave." For of these the formula of "snub" is stated in conjunction with the matter of the object, whereas that of "concave" is stated apart from the matter; since snubness is only found in the nose, which is therefore included in the formula, for "the snub" is a concave nose. Thus it is obvious that the formula of "flesh" and "eye" and the other parts of the body must always be stated in conjunction with their matter.
Since there is a science of Being qua Being and separately existent, we must inquire whether this should be regarded as identical with natural science or rather as a distinct branch of knowledge. Physics deals with things which contain a source of motion in themselves, and mathematics is speculative and is a science which deals with permanent things, but not with things which can exist separately. Hence there is a science distinct from both of these, which deals with that which exists separately and is immovable; that is, if there really is a substance of this kind—I mean separately existent and immovable—as we shall endeavor to prove. Aristot. Met. 12.6, 7. And if there is an entity of this kind in the world of reality, here surely must be the Divine, and this must be the first and most fundamental principle. Evidently, then, there are three kinds of speculative science: physics, mathematics, and theology. The highest class of science is the speculative, and of the speculative sciences themselves the highest is the last named, because it deals with the most important side of reality; and each science is reckoned higher or lower in accordance with the object of its study. The question might be raised as to whether the science of Being qua Being should be regarded as universal or not. Each of the mathematical sciences deals with some one class of things which is determinate, but universal mathematics is common to all alike. If, then, natural substances are the first of existing things, physics will be the first of the sciences; but if there is some other nature and substance which exists separately and is immovable, then the science which treats of it must be different from and prior to physics, and universal because of its priority. Since the term Being in its unqualified sense is used with several meanings, of which one is accidental Being, we must first consider Being in this sense. Sections 1-9 of this chapter correspond to Aristot. Met. 6.2-4.
Clearly none of the traditional sciences concerns itself with the accidental; the science of building does not consider what will happen to the occupants of the house, e.g. whether they will find it unpleasant or the contrary to live in; nor does the science of weaving or of shoemaking or of confectionery. Each of these sciences considers only what is proper to it, i.e. its particular end. As for the question whether "the cultured" is also "the lettered," or the quibble This is a different form of the "quibble" in Aristot. Met. 6.2.4. Here the fallacy obviously consists in the wrong application of the word A(/MA ("at once" or "at the same time"). that "the man who is cultured, when he has become lettered, will be both at once although he was not before; but that which is but was not always so must have come to be; therefore he must have become at the same time cultured and lettered" —none of the recognized sciences considers this, except sophistry. This is the only science which concerns itself with the accidental, and hence Plato was not far wrong in saying Plat. Sop. 254a. that the sophist spends his time in the study of unreality. But that it is not even possible for there to be a science of the accidental will be apparent if we try to see what the accidental really is. Of some things we say that they are so always and of necessity (necessity having the sense not of compulsion, but that which we use in logical demonstration Cf. Aristot. Met. 6.2.6. ), and of others that they are so usually, but of others that they are so neither usually nor always and of necessity, but fortuitously. E.g., there might be a frost at midsummer, although this comes about neither always and of necessity nor usually; but it might happen sometimes.
The accidental, then, is that which comes about, but not always nor of necessity nor usually. Thus we have now stated what the accidental is; and it is obvious why there can be no science of such a thing, because every science has as its object that which is so always or usually, and the accidental falls under neither of these descriptions. Clearly there can be no causes and principles of the accidental such as there are of that which is per se; otherwise everything would be of necessity. For if A is when B is, and B is when C is, and C is not fortuitously but of necessity, then that of which C was the cause will also be of necessity, and so on down to the last causatum, as it is called. (But this was assumed to be accidental.) Therefore everything will be of necessity, and the element of chance, i.e. the possibility of a thing's either happening or not, is entirely banished from the world of events. Even if we suppose the cause not to exist already but to be coming to be, the result will be the same; for everything will come to be of necessity. The eclipse tomorrow will come about if A does, and A will if B does, and B if C does; and in this way if we keep on subtracting time from the finite time between now and to-morrow, we shall at some point arrive at the present existing condition. Therefore since this exists, everything subsequent to it will happen of necessity, and so everything happens of necessity. As for "what is" in the sense of what is true or what is accidental, the former depends upon a combination in thought, and is an affection of thought (hence we do not look for the principles of Being in this sense, but only for those of objective and separable Being) the latter is not necessary but indeterminate (I mean the accidental); and of such a thing the causes are indefinite and cannot be reduced to a system. Teleology is found in events which come about in the course of nature or as a result of thought. This section is taken from Aristot. Physics 2.5, 6. It is "chance" <or "luck"> when one of these comes about by accident; for a thing may be a cause, just as it may exist, either per se or accidentally. Chance is an accidental cause of normally purposive teleological events. Hence chance and thought have the same sphere of action, for there is no purpose without thought. Causes from which chance results may come about are indeterminate; hence chance is inscrutable to human calculation, and is a cause only accidentally, but in the strictest sense is a cause of nothing. It is "good" or "bad luck" when the result is good or bad, and "good" or "bad fortune" when the result is on a large scale. Since nothing accidental is prior to that which is per se, neither are accidental causes prior. Therefore if chance or spontaneity is the cause of the universe, mind and nature are prior causes. The argument is stated more fully and clearly in Aristot. Physics 2.6ff.. Chance produces indirectly the effects produced directly by mind; and spontaneity is similarly related to nature. But the indirect cause presupposes the direct. The argument is directed against the Atomists. Cf. Aristot. Phys. 196a 24, Simplicius 327.24, Cicero De Nat. Deor. 1.66 ("nulla cogente natura, sed concursu quodam fortuito"). A thing may exist only actually or potentially, or actually and potentially; it may be a substance or a quantity or one of the other categories. There is no motion The discussion of motion in this chapter consists of extracts from Aristot. Physics 3.1-3.
apart from things, for change is always in accordance with the categories of Being i.e., change is substantial (generation and destruction); quantitative (increase and decrease); qualitative (alteration); spatial (locomotion). Cf. Aristot. Met. 11.12.1, 2.; and there is nothing which is common to these and in no one category. Each category belongs to all its members in two ways—e.g. substance, for this is sometimes the form of the thing and sometimes its privation; and as regards quality there is white and black; and as regards quantity, complete and incomplete; and as regards spatial motion there is up and down or light and heavy—so that there are as many forms of motion and change as there are of Being. This is inaccurate; see previous note. Now since every kind of thing is divided into the potential and the real, I call the actualization of the potential as such, What Aristotle means by this is explained more clearly in the following sections, which may be summarized thus. The material substrate, e.g.
bricks, etc., which is potentially a house, may be regarded (a) as potential material; in this sense it is actualized as bricks before building begins; (b) as potentially a house; in this sense when it is actualized it is no longer buildable but built, i.e., it is no longer potential; (c) as potentially buildable into a house. In this sense its actualization is conterminous with the process of building, and is incomplete (sect.11), and should not be described as E)NTELE/XEIA or "complete reality." But Aristotle often uses this term as synonymous with the vaguer E)NE/RGEIA.
motion. That this is a true statement will be clear from what follows. When the "buildable" in the sense in which we call it such exists actually, it is being built; and this is the process of building. The same is true of the processes of learning, healing, walking, jumping, ageing, maturing. Motion results when the complete reality itself exists, and neither sooner nor later. The complete reality, then, of that which exists potentially, when it is completely real and actual, not qua itself but qua movable, is motion. By qua I mean this. The bronze is potentially a statue; but nevertheless the complete reality of the bronze qua bronze is not motion. To be bronze is not the same as to be a particular potentiality; since if it were absolutely the same by definition the complete reality of the bronze would be a kind of motion; but it is not the same. (This is obvious in the case of contraries; for the potentiality for health and the potentiality for illness are not the same—for if they were, health and illness would be the same too—but the substrate which becomes healthy or ill, whether it is moisture or blood, is one and the same.) And since it is not the same, just as "color" and "visible" are not the same, it is the complete reality of the potential qua potential that is motion. It is evident that it is this, and that motion results when the complete reality itself exists, and neither sooner nor later.
For everything may sometimes be actual, and sometimes not; e.g. the "buildable" qua "buildable"; and the actualization of the "buildable" qua "buildable" is the act of building. For the actualization is either this—the act of building—or a house. But when the house exists, it will no longer be buildable; the buildable is that which is being built. Hence the actualization must be the act of building, and the act of building is a kind of motion. The same argument applies to the other kinds of motion. That this account is correct is clear from what the other authorities say about motion, and from the fact that it is not easy to define it otherwise. For one thing, it could not be placed in any other class; this is clear from the fact that some people Pythagoreans and Platonists. Cf. Aristot. Met. 1.5.6, Plat. Soph. 256d. identify it with otherness and inequality and not-being, none of which is necessarily moved; moreover change is no more into these or out of them than into or out of their opposites. The criticism implied is: If motion is identified with otherness, inequality, etc., then these concepts must be either (a) subjects of motion, which is absurd, or (b) termini of motion, in which case the same must be true of their contraries, since motion is between contraries. The reason for placing motion in this class is that it is considered to be indeterminate, and the principles in one of the columns of contraries are indeterminate, being privative; for none of them is a determinate thing or quality or any of the other categories. The reason for considering motion to be indeterminate is that it cannot be associated either with the potentiality or with the actuality of things; for neither that which is potentially nor that which is actually of a certain size is necessarily moved. And motion is considered to be a kind of actualization, but incomplete Cf. note on sect. 2 (end) above, and Aristot. Met.
9.6.7-10.; the reason of this is that the potential, of which it is the actualization, is incomplete. Thus it is difficult to comprehend what motion is; for we must associate it either with privation or with potentiality or with absolute actuality; and apparently none of these is possible. There remains, then, the account which we have given; that it is an actuality, and an actuality of the kind which we have described, which is hard to visualize but capable of existing. That motion is in the movable is evident; for it is the complete realization of the movable by that which is capable of causing motion, and the actualization of that which is capable of causing motion is identical with that of the movable. For it must be a complete realization of them both; since a thing is capable of moving because it has the potentiality, but it moves only when it is active; but it is upon the movable that it is capable of acting. Thus the actuality of both alike is one; just as there is the same interval from one to two as from two to one, and the hill up and the hill down are one, although their being is not one; the case of the mover and the thing moved is similar. This chapter consists of extracts from Aristot. Physics 3.4, 5, 7. The infinite is either (a) that which cannot be traversed because it is not its nature to be traversed (just as sound is by nature invisible); or (b) that which admits of an endless traverse; or (c) scarcely admits of traverse; or (d) which, though it would naturally admit of traverse or limit, does not do so.
Further, it may be infinite in respect of addition or of subtraction or of both. That the infinite should be a separate independent entity, The Pythagorean and Platonic view. and yet imperceptible, is impossible. For if it is neither magnitude nor plurality, but infinity itself is the essence of it, and not merely an accident, it must be indivisible; because that which is divisible is either magnitude or plurality. And if it is indivisible it cannot be infinite, except in the same way as sound is invisible.
But this is not what people mean by infinite; and it is not the infinite in this sense that we are investigating, but the infinite in the sense of the untraversable. Again, how can the infinite exist independently unless number and magnitude, of which infinity is an attribute, also exist independently? Aristotle has argued that they do not in Aristot. Met. 1.9.16-25. And further, if the infinite is accidental, it cannot, qua infinite, be an element of things; just as the invisible is not an element of speech, although sound is invisible. It is clear also that the infinite cannot exist actually. Otherwise any part of it which we might take would be infinite; for infinity and the infinite are the same, if the infinite is substance and is not predicated of a subject.
Therefore it is either indivisible, or if it is partible, the parts into which it is divisible are infinite. But the same thing cannot be many infinites; for just as a part of air is air, so a part of the infinite will be infinite, if the infinite is a substance and principle. Therefore it is impartible and indivisible. But this is impossible of the actually infinite, because it must be some quantity. Therefore infinity is an accidental attribute. But if so, as we have said, it cannot be it that is a principle, but that of which it is an accident: air According to Anaximenes; cf.
Theophrastus, Phys. Opin. Fr. 2 (Ritter and Preller 26). or "the even." According to the Pythagoreans.
Cf. Aristot. Met. 1.5.5. n The foregoing inquiry is general; but what follows will show that the infinite does not exist in sensible things. If the definition of a body is "that which is bounded by surfaces," then no body, whether sensible or intelligible, can be infinite nor can there be any separate and infinite number, since number or that which involves number is numerable. This is clearly shown by the following concrete argument. The infinite can neither be composite nor simple.
For (a) it cannot be a composite body if the elements are limited in number This is proved in Aristot. Physics 1.6.; for the contraries must be equal, and no one of them must be infinite; for if the potency of one of the two corporeal elements is in any way inferior, the finite element will be destroyed by the infinite. And every element cannot be infinite, because body is that which has extension in all directions, and the infinite is that which is extended without limit; so that if the infinite is corporeal it will be infinite in all directions. sc. and so no other body can exist beside it. Nor (b) can the infinite be any simple body; neither, as some Anaximander. It seems, however, that by A)/PEIRON he meant "indeterminate" or "undifferentiated," although he no doubt regarded this principle as "infinite" as well. Cf. notes on Aristot. Met. 1.7.3, Aristot. Met. 12.2.3. hold, something which is apart from the elements and from which they suppose the elements to be generated (for there is no such body apart from the elements; everything can be resolved into that of which it consists, but we do not see things resolved into anything apart from the simple bodies), nor fire nor any other element. Apart from the question of how any of them could be infinite, the All, even if it is finite, cannot be or become any one of the elements, as Heraclitus says Cf. Hereclitus Fr. 20-22 (Bywater). all things at certain times become fire. The same argument applies as to the One which the physicists posit besides the elements; for all change proceeds from the contrary, e.g. from hot to cold. The argument seems to be: Since all change is from contrary to contrary, and it is impossible that either (a) one of the elements should be contrary to the rest, or (b) one material principle should be contrary to all four elements, it follows that no one element, and similarly that no one material principle apart from the elements, can be the ultimate material principle of the universe. Again, a sensible body is in some region, and the region of the whole and of the part (e.g. of the earth) is the same. i.e., the region of the universe which is proper to a given element is proper also to any part of that element. The proper region of earth is the center, of fire the circumference of the universe.
Cf. Aristot. De Caelo 1.2. Therefore if the infinite body is homogeneous, it will be immovable or will always be in motion Ross is evidently right in taking this to refer to the rest or motion of the parts. An infinite body cannot move as a whole, because there is no space outside it.; but this is impossible, for why should there be rest or motion below rather than above or in any other region? E.g., if there were a clod, in what region would it move or be at rest? The region proper to the body which is homogeneous with the clod is infinite. Then will the clod occupy the whole of that region? How can it? Then what of its rest or motion? It will either rest everywhere—in which case it cannot move—or move everywhere; in which case it cannot rest. If earth is an infinite body, its region must be infinite. But the infinite has no center (cf. sect. 13).
Therefore a clod, which cannot occupy the whole region proper to earth, will have no region proper to itself to which it can move or in which it can rest. And if the whole is not alike throughout, the regions proper to its parts are unlike also; and (a) the body of the whole is not one, except in virtue of contact; (b) the parts will be either finite or infinite in kind. Finite they cannot be, for then those of one kind would be infinite sc. in quantity. If the universe is infinite in quantity, and the elements are limited in kind, some of the elements (or at least one) must be infinite in quantity. But this is impossible, just as it is impossible that all the elements should be infinite in quantity. Cf. sect. 7 above and those of another would not (if the whole is infinite); e.g., fire or water would be infinite. But such a condition would involve the destruction of the contraries. But if the parts are infinite sc. in kind or number. and simple, the regions proper to them are infinite and the elements will be infinite. And since this is impossible, Cf. sect. 6 n. the regions are finite Cf. sect. 14 n. and the whole must be finite. In general, there cannot be an infinite body and a place for bodies if every body which is sensible has either weight or lightness; for it will have to move either towards the center or upwards, and the infinite—either the whole or the half—cannot do either; for how can you divide it? How can the infinite be part up and part down, or part extreme and part center? Further, every sensible body is in some place, and of place there are six kinds, i.e., above and below, before and behind, right and left ( Aristot. Phys. 205b 31 ). but these cannot exist in an infinite body. In general, if an infinite place is impossible, so is an infinite body; because that which is in a place is somewhere, and this means either up or down or one of the other kinds of place, and each of these is a limit. The infinite is not the same in the sense that it is one nature whether it applies to magnitude or to motion or to time; the posterior is derived from the prior sense, e.g. motion is called infinite in virtue of the magnitude involved when a thing is moved or changed or increased, and time is so called on account of motion. Cf. Aristot. Met. 5.13.5.
That which changes either changes accidentally, as when "the cultured" walks; or is said to change in general because something in it changes, as in the case of things which change in their parts; the body becomes healthy because the eye does. But there is something which is moved directly per se, i.e. the essentially movable. The same applies to that which moves, for it moves sometimes accidentally, sometimes partially, and sometimes per se. There is something that moves directly, and something that is moved; and also a time in which, and something from which, and something into which it is moved. But the forms and modifications and place into which moving things are moved are immovable; e.g. knowledge and warmth. It is not warmth that is motion, but the process of warming.
Non-accidental change is not found in all things, but only between contraries and intermediates and contradictories. We can convince ourselves of this by means of induction. That which changes changes either from positive into positive, or from negative into negative, or from positive into negative, or from negative into positive. By "positive" I mean that which is denoted by an affirmation. Thus there must be three forms of change; for that which is from negative into negative is not change, because they are neither contraries nor contradictories, since they entail no opposition. The change from the negative into its contradictory positive is generation—absolute change absolute generation, and qualified change qualified generation; and the change from the positive to the negative is destruction—absolute change absolute destruction, and qualified change qualified destruction. The change from positive to positive is omitted here (but cf. sect. 7). Aristotle no doubt intended to use it as an example of non-substantial change, e.g.
from "poor man" to "rich man"; but since this can be regarded as change from "poor man " to "not-poor man," or "not-rich man" to "rich man," he includes it as a qualified type of substantial change. Now if "what is not" has several meanings, and neither that which implies a combination or separation of terms, i.e., falsity. Cf. Aristot. Met.
9.10.1. nor that which relates to potentiality and is opposed to unqualified Being, admits of motion ("not-white" or "not-good," however, admits of motion accidentally, because "not-white" may be a man; but that which is "not so-and-so" in an absolute sense does not admit of it at all), then "what is not" cannot be moved. If this is so, generation cannot be motion; for it is "what is not" that is generated. For even if the generation is in the highest degree accidental, still it is true to say that not-being is predicable of that which is generated absolutely. And the argument applies similarly to rest. Thus not only do these difficult conclusions follow, but also that everything which is moved is in a place, whereas "what is not" is not in a place; for then it would be somewhere. Nor is destruction motion; for the contrary of motion is motion or rest, but the contrary of destruction is generation. And since every motion is a kind of change, and the three kinds of change are those which we have described, sect. 3. and of these those which relate to generation and destruction are not motions, and these are the changes between contradictories, the change from positive to positive must alone be motion. The subjects are either contraries or intermediates (for privative terms may also be regarded as contraries) and are denoted by a positive term—e.g.
"naked" or "toothless" or "black." Now since the categories are distinguished as substance, quality, place, activity or passivity, relation and quantity, Aristotle generally distinguishes eight categories (originally ten, but he seems to have abandoned KEI=SQAI "position" and E)/XEIN "state" at an early date); here he omits "time" as being relative to motion (it is that by which motion can be numerically estimated; cf. Aristot. Met. 12.6.2, Aristot. Phys. 219b 1 ) and therefore neither the subject nor the terminus of motion. Cf.
Ross ad loc. there must be three kinds of motion, in respect of quality, quantity and place. There is no motion There is, however, change in respect of substance (generation and destruction), but this is between contradictories and is not motion in the strict sense. Cf. Aristot. Met. 11.11.6, and sect. 4 below. The distinction between motion and change is not always maintained. in respect of substance, because substance has no contrary; nor of the relative, because it is possible that when one of two related things changes the relation to it of the other thing, even though the thing itself does not change, may become untrue; therefore the motion of these related things is accidental. Nor is there motion of the agent or patient, or of the mover and the thing moved, because there is no motion of motion nor no generation of generation, nor in general is there change of change. There are two ways in which there might be motion of motion: (1) Motion might be the subject of motion, as, e.g., a man is moved because he changes from white to black; in this way motion might be heated or cooled or might change its place or increase. But this is impossible, because the change is not a subject. Or (2) some other subject might change from change to some other form of existence, as, e.g., a man changes from sickness to health. But this is also impossible except accidentally. Every motion is a change from one thing into something else; and the same is true of generation and destruction, except that these are changes into opposites in one sense, sc.
contradictories. while the other, i.e. motion, is a change into opposites in another sense. sc. contraries. Hence a thing changes at the same time from health to sickness, and from this change itself into another. Now clearly if it has fallen ill it will be already changed (for it cannot remain at rest) into that other change, whatever it may be; and further this cannot be, in any given case, any chance change; and it also must be from something into something else. Therefore it will be the opposite change, viz. becoming healthy. But this is so accidentally; just as there is change from recollecting to forgetting because the subject changes, now in the direction of knowledge and now in that of ignorance. Further, we shall have an infinite series if there is to be change of change and becoming of becoming, because if the latter of two becomings comes to be from the former, the former must come to be too. E.g., if simple becoming was once coming to be, that which comes to be something was also once coming to be. Therefore that which simply comes to be was not yet, but there was already something coming to be coming to be something. But this too was at one time coming to be, and therefore it was not