75 Cf. Phys. iii. 207b 21–25.
76 Cf. Phys. v. 224a 21–b 1.
77 Cf. Phys. v. 224b 11–16.
78 Cf. Phys. v. 224b 28–30.
79 Cf. vi. 1026a 33–b 2, 1027b 18–19.
80 i. e. to ‘that which is not’ in the sense of ‘the judgment which is false’.
81 i. e. a thing cannot be moved when it does not exist actually, but exists potentially.
82 i. e. even if the not-being (privation) which is the starting-point of generation can exist only as an accident of prime matter, still not-being is the starting-point of absolute generation (i. e. generation of a substance, not of a quality).
83 In 1067b 19.
84 Change between contraries is movement, change between contradictories is generation or destruction.
85 This is possible, though excluded by the theory in question.
86 With 1067b 14–1068b 15 Cf. Phys. v. 225a 3–226a 16.
87 Cf. Phys. v. 226a 23–29.
88 Cf. Phys. v. 226b 10–16.
89 Cf. Phys. v. 226b 21–25.
90 Cf. Phys. v. 226b 32–227a 31.
BOOK Λ (XII)
1 The subject of our inquiry is substance; for the principles and the causes we are seeking are those of substances. For if the universe is of the nature of a whole, (20) substance is its first part; and if it coheres merely by virtue of serial succession, on this view also substance is first, and is succeeded by quality, and then by quantity. At the same time these latter are not even being in the full sense, but are qualities and movements of it—or else even the not-white and the not-straight would be being; at least we say even these are, e. g. ‘there is a not-white’.1 Further, (25) none of the categories other than substance can exist apart. And the early philosophers also in practice testify to the primacy of substance; for it was of substance that they sought the principles and elements and causes. The thinkers of the present2 day tend to rank universals as substances (for genera are universals, and these they tend to describe as principles and substances, owing to the abstract nature of their inquiry); but the thinkers of old ranked particular things as substances, e. g. fire and earth, not what is common to both, body.
There are three kinds of substance—one that is sensible (of which one subdivision is eternal and another is perishable; the latter is recognized by all men, (30) and includes e. g. plants and animals), of which we must grasp the elements, whether one or many; and another that is immovable, and this certain thinkers assert to be capable of existing apart, (35) some dividing it into two, others identifying the Forms and the objects of mathematics, and others positing, of these two, only the objects of mathematics.3 The former two kinds of substance are the subject of physics (for they imply movement); but the third kind belongs to another science, if there is no principle common to it and to the other kinds. [1069b]
2 Sensible substance is changeable. Now if change proceeds from opposites or from intermediates, and not from all opposites (for the voice is not-white [but it does not therefore change to white]), (5) but from the contrary, there must be something underlying which changes into the contrary state; for the contraries do not change. Further, something persists, but the contrary does not persist; there is, then, some third thing besides the contraries, viz. the matter. Now since changes are of four kinds—either in respect of the ‘what’ or of the quality or of the quantity or of the place, (10) and change in respect of ‘thisness’ is simple generation and destruction, and change in quantity is increase and diminution, and change in respect of an affection is alteration, and change of place is motion, changes will be from given states into those contrary to them in these several respects. The matter, then, which changes must be capable of both states. (15) And since that which ‘is’ has two senses, we must say that everything changes from that which is potentially to that which is actually, e. g. from potentially white to actually white, and similarly in the case of increase and diminution. Therefore not only can a thing come to be, incidentally, out of that which is not, but also all things come to be out of that which is, but is potentially, and is not actually. And this is the ‘One’ of Anaxagoras; for instead of ‘all things were together’—and the ‘Mixture’ of Empedocles and Anaximander and the account given by Democritus—it is better to say ‘all things were together potentially but not actually’. (20) Therefore these thinkers seem to have had some notion of matter. Now all things that change have matter, (25) but different matter; and of eternal things those which are not generable but are movable in space have matter—not matter for generation, however, but for motion from one place to another.
One might raise the question from what sort of non-being generation proceeds; for ‘non-being’ has three senses. If, then, one form of nonbeing exists potentially, still it is not by virtue of a potentiality for any and every thing, but different things come from different things; nor is it satisfactory to say that ‘all things were together’; for they differ in their matter, (30) since otherwise why did an infinity of things come to be, and not one thing? For ‘reason’ is one, so that if matter also were one, that must have come to be in actuality which the matter was in potency.4 The causes and the principles, then, are three, two being the pair of contraries of which one is definition and form and the other is privation, and the third being the matter.
3 Note, next, that neither the matter nor the form comes to be—and I mean the last matter and form. (35) For everything that changes is something and is changed by something and into something. [1070a] That by which it is changed is the immediate mover; that which is changed, the matter; that into which it is changed, the form. The process, then, will go on to infinity, if not only the bronze comes to be round but also the round or the bronze comes to be; therefore there must be a stop.
Note, next, that each substance comes into being out of something that shares its name. (Natural objects and other things both rank as substances.) (5) For things come into being either by art or by nature or by luck or by spontaneity. Now art is a principle of movement in something other than the thing moved, nature is a principle in the thing itself (for man begets man), and the other causes are privations of these two.
There are three kinds of substance—the matter, which is a ‘this’ in appearance (for all things that are characterized by contact and not by organic unity are matter and substratum, (10) e. g. fire, flesh, head; for these are all matter, (19) and the last matter is the matter of that which is in the full sense substance); the nature, (11) which is a ‘this’ or positive state towards which movement takes place; and again, thirdly, the particular substance which is composed of these two, e. g. Socrates or Callias. Now in some cases the ‘this’ does not exist apart from the composite substance, e. g. the form of house does not so exist, (15) unless the art of building exists apart (nor is there generation and destruction of these forms, but it is in another way that the house apart from its matter, and health, and all ideals of art, exist and do not exist); but if the ‘this’ exists apart from the concrete thing, it is only in the case of natural objects. And so Plato was not far wrong when he said that there are as many Forms as there are kinds of natural object (if there are Forms distinct from the things of this earth). (21) The moving causes exist as things preceding the effects, but causes in the sense of definitions are simultaneous with their effects. For when a man is healthy, then health also exists; and the shape of a bronze sphere exists at the same time as the bronze sphere. (25) (But we must examine whether any form also survives afterwards. For in some cases there is nothing to prevent this; e. g. the soul may be of this sort—not all soul but the reason; for presumably it is impossible that all soul should survive.) Evidently then there is no necessity, on this ground at least, for the existence of the Ideas. For man is begotten by man, a given man by an individual father; and similarly in the arts; for the medical art is the formal cause of health. (30)
4 The causes and the principles of different things are in a sense different, but in a sense, if one speaks u
niversally and analogically, they are the same for all. For one might raise the question whether the principles and elements are different or the same for substances and for relative terms, (35) and similarly in the case of each of the categories. But it would be paradoxical if they were the same for all. For then from the same elements will proceed relative terms and substances. [1070b] What then will this common element be? For (1) (a) there is nothing common to and distinct from substance and the other categories, viz. those which are predicated; but an element is prior to the things of which it is an element. But again (b) substance is not an element in relative terms, nor is any of these an element in substance. Further, (2) how can all things have the same elements? For none of the elements can be the same as that which is composed of elements, (5) e. g. b or a cannot be the same as ba. (None, therefore, of the intelligibles, e. g. being or unity, is an element; for these are predicable of each of the compounds as well.) None of the elements, then, will be either a substance or a relative term; but it must be one or other. All things, then, have not the same elements.
Or, as we are wont to put it, (10) in a sense they have and in a sense they have not; e. g. perhaps the elements of perceptible bodies are, as form, the hot, and in another sense the cold, which is the privation; and, as matter, that which directly and of itself potentially has these attributes; and substances comprise both these and the things composed of these, of which these are the principles, or any unity which is produced out of the hot and the cold, e. g. flesh or bone; for the product must be different from the elements. (15) These things then have the same elements and principles (though specifically different things have specifically different elements); but all things have not the same elements in this sense, but only analogically; i. e. one might say that there are three principles—the form, the privation, and the matter. But each of these is different for each class; e. g. in colour they are white, (20) black, and surface, and in day and night they are light, darkness, and air.
Since not only the elements present in a thing are causes, but also something external, i. e. the moving cause, clearly while ‘principle’ and ‘element’ are different both are causes, and ‘principle’ is divided into these two kinds5 and that which acts as producing movement or rest is a principle and a substance. Therefore analogically there are three elements, (25) and four causes and principles; but the elements are different in different things, and the proximate moving cause is different for different things. Health, disease, body; the moving cause is the medical art. Form, disorder of a particular kind, bricks; the moving cause is the building art. And since the moving cause in the case of natural things is—for man, (30) for instance, man, and in the products of thought the form or its contrary, there will be in a sense three causes, while in a sense there are four. For the medical art is in some sense health, and the building art is the form of the house, and man begets man;6 further, besides these there is that which as first of all things moves all things. (35)
5 Some things can exist apart and some cannot, and it is the former that are substances. [1071a] And therefore all things have the same causes,7 because, without substances, modifications and movements do not exist. Further, these causes will probably be soul and body, or reason and desire and body.
And in yet another way, (5) analogically identical things are principles, i. e. actuality and potency; but these also are not only different for different things but also apply in different ways to them. For in some cases the same thing exists at one time actually and at another potentially, e. g. wine or flesh or man does so. (And these two fall under the above-named causes.8 For the form exists actually, if it can exist apart, and so does the complex of form and matter, (10) and the privation, e. g. darkness or disease; but the matter exists potentially; for this is that which can become qualified either by the form or by the privation.) But the distinction of actuality and potentiality applies in another way to cases where the matter of cause and of effect is not the same, in some of which cases the form is not the same but different; e. g. the cause of man is (1) the elements in man (viz. fire and earth as matter, and the peculiar form), and further (2) something else outside, (15) i. e. the father, and (3) besides these the sun and its oblique course, which are neither matter nor form nor privation of man nor of the same species with him, but moving causes.
Further, one must observe that some causes can be expressed in universal terms, and some cannot. The proximate principles of all things are the ‘this’ which is proximate in actuality, and another which is proximate in potentiality.9 The universal causes, then, (20) of which we spoke10 do not exist. For it is the individual that is the originative principle of the individuals. For while man is the originative principle of man universally, there is no universal man, but Peleus is the originative principle of Achilles, and your father of you, and this particular b of this particular ba, though b in general is the originative principle of ba taken without qualification.
Further, if the causes of substances are the causes of all things, yet different things have different causes and elements, as was said11; the causes of things that are not in the same class, (25) e. g. of colours and sounds, of substances and quantities, are different except in an analogical sense; and those of things in the same species are different, not in species, but in the sense that the causes of different individuals are different, your matter and form and moving cause being different from mine, while in their universal definition they are the same. And if we inquire what are the principles or elements of substances and relations and qualities—whether they are the same or different—clearly when the names of the causes are used in several senses the causes of each are the same, (30) but when the senses are distinguished the causes are not the same but different, except that in the following senses the causes of all are the same. They are (1) the same or analogous in this sense, that matter, form, privation, and the moving cause are common to all things; and (2) the causes of substances may be treated as causes of all things in this sense, that when substances are removed all things are removed; further, (35) (3) that which is first in respect of complete reality is the cause of all things. But in another sense there are different first causes, viz. all the contraries which are neither generic nor ambiguous terms; and, further, the matters of different things are different. [1071b] We have stated, then, what are the principles of sensible things and how many they are, and in what sense they are the same and in what sense different.
6 Since there were12 three kinds of substance, two of them physical and one unmovable, regarding the latter we must assert that it is necessary that there should be an eternal unmovable substance. For substances are the first of existing things, and if they are all destructible, (5) all things are destructible. But it is impossible that movement should either have come into being or cease to be (for it must always have existed), or that time should. For there could not be a before and an after if time did not exist. Movement also is continuous, then, in the sense in which time is; for time is either the same thing as movement or an attribute of movement. And there is no continuous movement except movement in place, (10) and of this only that which is circular is continuous.
But if there is something which is capable of moving things or acting on them, but is not actually doing so, there will not necessarily be movement; for that which has a potency need not exercise it. Nothing, then, is gained even if we suppose eternal substances, as the believers in the Forms do, unless there is to be in them some principle which can cause change; nay, (15) even this is not enough, nor is another substance besides the Forms enough; for if it is not to act, there will be no movement. Further, even if it acts, this will not be enough, if its essence is potency; for there will not be eternal movement, since that which is potentially may possibly not be. There must, (20) then, be such a principle, whose very essence is actuality. Further, then, these substances must be without matter; for they must be eternal, if anything is eternal. Therefore they must be actuality.
Yet there is a diff
iculty; for it is thought that everything that acts is able to act, but that not everything that is able to act acts, (25) so that the potency is prior. But if this is so, nothing that is need be; for it is possible for all things to be capable of existing but not yet to exist.
Yet if we follow the theologians who generate the world from night, or the natural philosophers who say that ‘all things were together’,13 the same impossible result ensues. For how will there be movement, if there is no actually existing cause? Wood will surely not move itself—the carpenter’s art must act on it; nor will the menstrual blood nor the earth set themselves in motion, (30) but the seeds must act on the earth and the semen on the menstrual blood.
This is why some suppose eternal actuality—e. g. Leucippus14 and Plato15; for they say there is always movement. But why and what this movement is they do not say, nor, if the world moves in this way or that, do they tell us the cause of its doing so. Now nothing is moved at random, (35) but there must always be something present to move it; e. g. as a matter of fact a thing moves in one way by nature, and in another by force or through the influence of reason or something else. (Further, what sort of movement is primary? This makes a vast difference.) But again for Plato, at least, it is not permissible to name here that which he sometimes supposes to be the source of movement—that which moves itself;16 for the soul is later, and coeval with the heavens, according to his account.17 [1072a] To suppose potency prior to actuality, then, is in a sense right, and in a sense not; and we have specified these senses.18 That actuality is prior is testified by Anaxagoras (for his ‘reason’ is actuality) and by Empedocles in his doctrine of love and strife, (5) and by those who say that there is always movement, e. g. Leucippus. Therefore chaos or night did not exist for an infinite time, but the same things have always existed (either passing through a cycle of changes or obeying some other law), since actuality is prior to potency. If, then, there is a constant cycle, (10) something must always remain,19 acting in the same way. And if there is to be generation and destruction, there must be something else20 which is always acting in different ways. This must, then, act in one way in virtue of itself, and in another in virtue of something else—either of a third agent, therefore, or of the first. Now it must be in virtue of the first. For otherwise this again causes the motion both of the second agent and of the third. Therefore it is better to say ‘the first’. (15) For it was the cause of eternal uniformity; and something else is the cause of variety, and evidently both together are the cause of eternal variety. This, accordingly, is the character which the motions actually exhibit. What need then is there to seek for other principles?
The Basic Works of Aristotle (Modern Library Classics) Page 122