METAPHYSICS, BOOK XII
Mobile and Immobile Substance
The Prime Mover
Lesson 1: Metaphysics Studies Substance
Lesson 2: Three Classes of Substances
Lesson 3:Characteristics of Forms
Lesson 4: The Principles of Movable Substances
Lesson 5: An Eternal Immovable Substance Must Exist
Lesson 6: Eternal Motion Requires An Eternal Mover
Lesson 7: How the First Mover Causes Motion
Lesson 8: The Perfection of the First Substance
Lesson 9: The Number of Primary Movers
Lesson 10: The Number of Unmoved Movers
Lesson 11: The Dignity of the First Intelligence
Lesson 12: God Is the Final Cause of All Things. The Order of the Universe
LESSON I: Metaphysics Studies Substance
ARISTOTLE’S TEXT Chapter 1: 1069a 18-1069a 30
1023. The study here is concerned with substance; for it is the principles and causes of substances which are being investigated.
1024. For if the totality of things is a kind of whole, substance is its first part; and if things constitute a whole by reason of succession, substance is also first, and then quality or quantity.
1025. And in like manner the latter are not to be regarded as beings in an unqualified sense, but as qualities and motions of being. Otherwise the not-straight and not-white would be beings; for we say that they are, for example, “the not-white is.”
1026. Again, none of the other genera can exist separately.
1027. The ancient philosophers testify to this in practice, for it was of substance that they sought the principles, elements and causes. Present-day thinkers [Platonists] however, maintain that universals are substances; for genera are universals, and they say that these are principles and substances to a greater degree because they investigate the matter dialectically. But the ancient philosophers regarded particular things as substances, for example, fire and earth, and not a common body.
2416. Having summarized in the preceding book the points that were previously made regarding imperfect being both in this work and in the Physics, in this book the Philosopher aims to summarize the things that have been said about being in its unqualified sense, i.e., substance, both in Books VII and VIII of this work and in Book I of the Physics, and to add anything that is missing in order to make his study of substances complete. This is divided into two parts. First (1023:C 2416), he shows that this science is chiefly concerned with substances. Second (1028:C 2424), he gives his views about the classes of substances (“Now there are three”).
In regard to the first he does two things. First, he states his thesis. He says that in this science “the study,” i.e., the principal inquiry, has to do with substances. For since this science, being the first and the one called wisdom, investigates the first principles of beings, the principles and causes of substances must constitute its main object of study; for these are the first principles of beings. The way in which principle and cause differ has been pointed out in Book V (403:C 760).
2417. For if the totality (1024)
He proves his thesis in four ways. The first proof runs thus. Since substance is prior to the other kinds of beings, the first science should be one that is chiefly concerned with the primary kind of being. He shows that substance is the primary kind of being by using an analogous case in the realm of sensible things, among which order is found in two ways. One kind of order is found among sensible things inasmuch as the parts of any whole have a certain natural arrangement; for example, the first part of an animal is the heart, and the first part of a house the foundation. Another kind of order is found among sensible things inasmuch as some follow others and one thing is not constituted from them either by continuity or by contact. It is in this sense that one speaks of the first and second lines of an army. Hence, just as there is some first part in any whole, and also some first entity among things that follow one another, so too substance is the first of all other beings. This is what he means when he says “For if the totality,” i.e., the universe of beings, is a kind of whole, substance is its first part, just as the foundation is the first part of a house. And if beings are like things that follow one another, substance again will be first, and then quantity, and then the other categories.
2418. But Averroes, failing to consider that this statement is analogical because he considered it impossible for anyone to think that all the other genera of beings should be parts of one continuous whole, departs from the obvious sense of the text and explains it in a different way. He says that by these two orders Aristotle meant the twofold relationship which can be conceived between things. The first is that beings are related as things having one nature and one genus, which would be true if being were their common genus, or in whatever way it might be common to them. He says that this is Aristotle’s meaning when he says “If the totality of things is a kind of whole.” The second is that beings are related as things having nothing in common. He says that this is Aristotle’s meaning when he says “And if things constitute a whole by reason of succession”; for in either case it follows that substance is prior to the other kinds of being.
2419. But in like manner (1025).
Then he gives a second proof of his thesis. He says that quantity and quality and the like are not beings in an unqualified sense, as will be said below. For being means something having existence, but it is substance alone that subsists. And accidents are called beings, not because they are but rather because by them something is; for example, whiteness is said to be because by it the subject is white. Hence Aristotle says that accidents, as quality and motion, are not called beings in an unqualified sense, but beings of a being.
2420. Nor is it surprising if accidents are called beings even though they are not beings in an unqualified sense, because even privations and negations are called beings in a sense, for example, the not-white and the not-straight. For we say that the not-white is, not because the not-white has being, but because some subject is deprived of whiteness. Accidents and privations have this in common, then, that being is predicated of both by reason of their subject. Yet they differ in this respect that, while a subject has being of some kind by reason of its accidents, it does not have being of any kind by reason of privations, but is deficient in being.
2421. Therefore, since accidents are not beings in an unqualified sense, but only substances are, this science, which considers being as being, is not chiefly concerned with accidents but with substances.
2422. Again, none (1026).
Then he gives a third proof of his thesis that the other kinds of beings cannot exist apart from substance. For accidents can exist only in a subject, and therefore the study of accidents is included in that of substance.
2423. The ancient philosophers (1027).
He gives a fourth proof of his thesis. He says that the ancient philosophers also testify to the fact that the philosopher is concerned with substances, because in seeking the causes of being they looked for the causes only of substance. And some of the moderns also did this, but in a different way; for they did not seek principles, causes and elements in the same way, but differently. For the moderns—the Platonists—claimed that universals are substances to a greater degree than particular things; for they said that genera, which are universals, are principles and causes of substances to a greater degree than particular things. They did this because they investigated things from the viewpoint of dialectics; for they thought that universals, which are separate according to their mode of definition from sensible things, are also separate in reality, and that they are the principles of particular things. But the ancient philosophers, such as Democritus and Empedocles, claimed that the substances and principles of things are particular entities, such as fire and earth, but not this common principle, body.
Three Classes of Substances
ARISTOTLE’S TEXT Chapters 1 & 2: 1069a 30-1069b 32
1028. Now there are three classes of substances. One is sensible, and of this class one kind is eternal and another perishable. The latter, such as plants and animals, all men recognize. But it is the eternal whose elements we must grasp, whether they are one or many. Another class is the immovable, which certain thinkers claim to have separate existence, some dividing it into two kinds, others maintaining that the separate Forms and the objects of mathematics are of one nature, and still others a holding that only the objects of mathematics belong to this class. The first two classes of substance belong to the philosophy of nature since they involve motion; but the last belongs to a different science if there is no principle common to these three.
1029. Sensible substance is capable of being changed. And if change proceeds from opposites or from intermediates, yet not from all opposites (for the spoken word is not white) but only from a contrary, then there must be some underlying subject which can be changed from one contrary to another; for contraries themselves are not changed (730). Further, this subject remains, whereas a contrary does not remain. Therefore there is some third thing besides the contraries, and this is matter.
1030. If, then, there are four kinds of change: either in substance or in quality or in quantity or in place, and if change in substance is generation and destruction without qualification, and change in quantity is increase and decrease, and change in attribute is alteration, and change in place is local motion, then the changes occurring in each case must be changes to contrary states. Therefore it must be the matter which is capable of being changed to both states.
1031. And since being is twofold, every change is from potential being to actual being, for example, from potentially white to actually white. The same is true of increase and decrease. Hence not only can a thing come to be accidentally from nonbeing, but all things come to be from being, i.e., from potential being, not from actual being.
1032. And this is the “One” of Anaxagoras; for it is better to maintain this view than to claim that “all things were together.” And this is the “Mixture” of Empedocles and Anaximander, and it recalls the statement of Democritus that all things were together potentially but not at all actually.s Hence all these thinkers were touching upon matter.
1033. Now all things which undergo change have matter, but different things have different matters; and of eternal things, those which are incapable of being generated but can be moved by local motion have matter. Yet they do not have that kind of matter which is subject to generation, but only such as is subject to motion from one place to another (697).
1034. And one might raise the question from what kind of non-being generation could come about; for non-being is spoken of in three senses. If, then, one kind of non-being is potentiality, still it is not from anything at all that a thing comes to be, but different things come from different things. Nor is it enough to say that “all things were together,” since they differ in their matter, for otherwise why would an infinite number of things be generated and not just one thing? For mind is one, so that if matter were also one, only that could come to be actually whose matter was in potentiality.
2424. Having explained that philosophy is concerned chiefly with substances, here the Philosopher begins to deal with substances. This is divided into two parts. In the first (1028:C 2424) he makes a division of substance; and in the second (1029:C 2428) he treats the parts of this division (“Sensible substance”).
He accordingly says, first (1028), that there are three classes of substances. One is sensible, and this is divided into two kinds; for some sensible substances are eternal (the celestial bodies) and others perishable. Sensible and perishable substances, such as animals and plants, are recognized by all.
2425. But it is “the other class of sensible substance,” i.e., the eternal, whose principles we aim to discover in this book, whether their principles are one or many. He will investigate this by considering the separate substances, which arc both the sources of motion and the ends of the celestial bodies, as will be made clear below (1086:C 2590-92). He uses elements in the broad sense here in place of principles; for strictly an element is only an intrinsic cause.
2426. The third class of substance is the immovable and imperceptible. This class is not evident to all, but some men claim that it is separate from sensible things. The opinions of these men differ; for some divide separate substances into two kinds—the separate Forms, which they call Ideas, and the objects of mathematics. For just as a twofold method of separating is found in reason, one by which the objects of mathematics are separated from sensible matter, and another by which universals are separated from particular things, in a similar way they maintained that both universals, which they called separate Forms, and also the objects of mathematics, are separate in reality. But others reduced these two classes—the separate Forms and the objects of mathematics—to one nature. Both of these groups were Platonists. But another group, the Pythagoreans, did not posit separate Forms, but only the objects of mathematics.
2427. Among these three classes of substances there is this difference, namely, that sensible substances, whether they are perishable or eternal, belong to the consideration of the philosophy of nature, which establishes the nature of movable being; for sensible substances of this kind are in motion. But separable and immovable substances belong to the study of a different science and not to the, same science if there is no principle common to both kinds of substance; for if there were a common principle, the study of both kinds of substance would belong to the science which considers that common principle. The philosophy of nature, then, considers sensible substances only inasmuch as they are actual and in motion. Hence this science (first philosophy) considers both sensible substances and immovable substances inasmuch as both are beings and substances.
2428. Sensible substance (1029).
Then he establishes the truth about the above-mentioned substances. He does this, first (1029:C 2429), with regard to sensible substances; and second (1055:C 2488), with regard to immovable substances (“And since there are three”).
The first is divided into two parts. First, he investigates the principles of sensible substances; and second (1042:C 2455), he inquires whether the principles of substances and those of the other categories are the same (“In one sense”).
In regard to the first he does two things. First, he investigates the nature of matter; and second (1035:C 2440, the nature of form (“The causes or principles”).
In regard to the first he does two things. First, he states his views about matter. Second (1034:C 2437), he meets a difficulty (“And one might raise the question”).
In regard to the first he does two things. First, he shows that there is matter in sensible substances; and he also shows what kind of being matter is. Second (1033:C 2436), he shows how matter differs in different kinds of sensible substances (“Now all things”).
In regard to the first he does two things. First, he proceeds as described. Second (1031:C 2432), he meets an argument by which some of the ancient philosophers denied generation (“And since being is twofold”).
In regard to the first he does two things. First, he shows that there is matter in sensible substances. Second (1030:C 431), he shows what kind of being matter is (“If, then, there are”).
He accordingly says, first (1029), that sensible substance is changeable, as has been pointed out, and every change is either from opposites or from intermediates, as has been shown above (384:C 723-24). Yet change does not proceed from any opposites whatever; for the white comes from the not-white, but not from just any not-white; for a word is not-white, yet a body does not become white from a word, but from a not-white which is black or some intermediate color. Hence he says that change proceeds from an opposite which is a contrary. And there can be no rejoinder based on change in substance on the ground that there is nothing contrary to substance. For in substance there is privation which is included in a sense among contraries, as has been shown in Book X (853:C 2050-53).
2429. Hence, since every change is from one contrary to another, there must be some underlying subject which can be changed from one contrary to another. The Philosopher proves this in two ways. First, he argues on the ground that one contrary is not changed into another; for blackness itself does not become whiteness, so that, if there is a change from black to white, there must be something besides blackness which becomes white.
2430. He proves the same point in another way, namely, from the fact that throughout every change something is found to remain. For example, in a change from black to white a body remains, whereas the other thing —the contrary black—does not remain. Therefore it is evident that matter is some third entity besides the contraries.
2431. If, then, there are (1030).
He now shows what kind of being matter is. He says that there are four kinds of change: simple generation and destruction, which is change in substance; increase and decrease, which is change in quantity; alteration, which is change in affections (and constitutes the third species of quality); and “local motion,” or change of place, which pertains to the where of a thing. Now it has been shown that all of these changes involve the contrarieties that belong to each of these classes; for example, alteration involves contrariety of quality, increase involves contrariety of quantity, and so on for the others. And since in every change there is besides the contraries some third entity which is called matter, the thing undergoing the change, i.e., the subject of the change, considered just in itself, must be in potentiality to both contraries, otherwise it would not be susceptible of both or admit of change from one to the other. Thus, just as a body which is changed from white to black, qua body, is in potentiality to each of the two contraries, in a similar way in the generation of substance the matter, as the subject of generation and destruction, is of itself in potentiality both to form and to privation, and has actually of itself neither form nor privation.
2432. And since being (1031).
Here the Philosopher establishes the truth about matter itself, and in regard to this he does two things. First, he meets a difficulty. Second (1032:C 2435), he shows how some of the ancient philosophers offered a solution similar to the one mentioned above (“And this is the ‘One’”).
He meets the difficulty of the ancient philosophers who did away with generation because they did not think that anything could come from non-being, since nothing comes from nothing, or that anything could come from being, since a thing would then be before it came to be.
2433. The Philosopher meets this difficulty by showing how a thing comes to be both from being and from non-being. He says that being is twofold—actual and potential. Hence everything which is changed is changed from a state of potential being to one of actual being; for example, a thing is changed from being potentially white to being actually white. The same thing holds true of the motion of increase and decrease, since something is changed from being potentially large or small to being actually large or small. In the category of substance, then, all things come to be both from being and from non-being. A thing comes to be accidentally from non-being inasmuch as it comes to be from a matter subject to privation, in reference to which it is called non-being. And a thing comes to be essentially from being—not actual being but potential being—i.e., from matter, which is potential being, as has been shown above (1030:C 2431).
2434. Now it should be borne in mind that certain later thinkers wanted to oppose the above-mentioned principle of the ancient philosophers of nature (who denied generation and destruction and claimed that generation is merely alteration) when they said that generation comes about through detachment from some mixture or confused mass.
2435. Hence, when the Philosopher in the third part of his division says “And this is the one (1032),” he shows that all who expressed this view wanted to adopt a position similar to the one mentioned above, but did not succeed in doing so. Therefore he says that this, namely, matter, which is in potentiality to all forms, is the “One” of which Anaxagoras spoke; for Anaxagoras said that everything which is generated from something else is present in that thing from which it comes to be. And so, not knowing how to distinguish between potentiality and actuality, he said that in the beginning all things were mixed together in one whole. But it is more fitting to posit a matter in which all things are present potentially than to posit one in which all things are present actually and simultaneously, as seems to be the case from what Anaxagoras said. This is what Empedocles also claimed, namely, that in the beginning all things were mixed or mingled together by friendship and later were separated out by strife. Anaximander similarly held that all contraries originally existed in one confused mass. And Democritus said that everything which comes to be first exists potentially and then actually. Hence it is evident that all these philosophers touched upon matter to some extent but did not fully comprehend it.
2436. Now all things (1033).
He shows that matter is not present in all sensible substances in the same way. He says that all things which undergo change must have matter, but of a different kind. For things which “are changed substantially,” i.e., generated and destroyed, have a matter which is subject to generation and destruction, i.e., one which is in itself in potentiality both to forms and to privations. But the celestial bodies, which are eternal and not subject to generation, yet admit of change of place, have matter—not one which admits of generation and destruction or one which is in potentiality to form and to privation, but one which is in potentiality to the termini of local motion, i.e., the point from which motion begins and the point to which it tends.
2437. And one might raise (1034).
Then he meets a difficulty that pertains to the points established above. He says that, since generation is a change from non-being to being, one can ask from what sort of non-being generation proceeds; for non-being is said of three things. First, it is said of what does not exist in any way; and from this kind of non-being nothing is generated, because in reality nothing comes from nothing. Second, it is said of privation, which is considered in a/,subject; and while something is generated from this kind of non-being, the generation is accidental, i.e., inasmuch as something is generated from a subject to which some privation occurs. Third, it is said of matter itself, which, taken in itself, is not an actual being but a potential one. And from this kind of non-being something is generated essentially; or in his words, if one kind of non-being is potentiality, then from such a principle, i.e., non-being, something is generated essentially.
2438. Yet even though something is generated from that kind of non-being which is being in potentiality, still a thing is not generated from every kind of non-being, but different things come from different matters. For everything capable of being generated has a definite matter from which it comes to be, because there must be a proportion between form and matter. For even though first matter is in potentiality to all forms, it nevertheless receives them in a certain order. For first of all it is in potency to the forms of the elements, and through the intermediary of these, insofar as they are mixed in different proportions, it is in potency to different forms. Hence not everything can come to be directly from everything else unless perhaps by being resolved into first matter.
2439. This view is opposed to that of Anaxagoras, who claimed that anything at all comes to be from anything else. Nor is his assumption that all things were together in the beginning sufficient to support this view. For things differ by reason of matter inasmuch as there are different matters for different things. For if the matter of all things were one, as it is according to the opinion of Anaxagoras, why would an infinite number of things be generated and not just one thing? For Anaxagoras claimed that there is one agent, mind; and therefore, if matter too were one, only one thing would necessarily come to be, namely, that to which matter is in potentiality. For where there is one agent and one matter there must be one effect, as has been stated in Book X.
2440. This argument holds good against Anaxagoras inasmuch as he claimed that mind needs matter in order to produce some effect. And if he claims that the first principle of things is mind, which produces matter itself, the first principle of the diversity of things will proceed from the order apprehended by the above-mentioned mind, which, inasmuch as it aims to produce different things, establishes different matters having an aptitude for a diversity of things.
Characteristics of Forms
ARISTOTLE’S TEXT Chapters 2 & 3: 1069b 32-1070a 30
1035. The causes or principles of things, then, are three. Two of these are the pair of contraries, of which one is the formal determinant or specifying principle, and the other the privation, and the third, matter.
1036. It should be noted next that neither matter nor form comes to be, and I mean the last matter and form. For everything which changes something else changes it from something to something. That by which it is changed is the first [i.e., immediate] mover; that which is changed is the matter; and that to which it is changed is the form. Hence there will be an infinite regress if not only the bronze becomes round but also roundness itself or bronze comes to be. Therefore there must be some stopping point.
1037. Again, it should be noted that every substance comes to be from something having the same name; for both things which are by nature as well as other things are substances. For things come to be either by art or by nature or by luck or spontaneously. Art is a principle in another, but nature is a principle in the subject itself; for man begets man. The remaining causes are the privations of these.
1038. There are three kinds of substance. First, there is matter, which is a particular thing in appearance; for whatever things are one by contact and not by natural union are matter and subject. Second, there is the nature [i.e., the form], which is a determinate thing inasmuch as it is a kind of positive state; and third, there is the singular thing which is composed of these, such as Socrates or Callias.
1039. Now in some cases the “this” [i.e., the form] does not exist apart from the composite substance; for example, the form of a house, unless it is the art. Nor is there generation and destruction of these forms, but it is in a different sense that house apart from matter, and health, and everything which comes to be by art, do and do not exist. But if the “this” does exist apart from matter, it is only in the case of those things which are by nature. Hence Plato was not wrong in saying that the Forms are things which exist by nature, i.e., if there are separate Forms different from these other things, such as fire, flesh and head. For all of these are matter, and they are the ultimate matter of substance in the fullest sense.
1040. Hence efficient causes are causes as things which are prior to their effects; but those things which are causes in the sense of the formal determinant are simultaneous with their effects. For it is when a man becomes healthy that health also exists; and the shape of the bronze sphere comes to be at the same time as the bronze sphere. But whether any form continues to exist afterwards is a question that requires investigation. For nothing prevents this from being so in certain cases, for example, if the soul is of this sort, not every soul but the intellectual; for perhaps it is impossible that every soul should continue to exist.
1041. It is evident, then, that it is not necessary on these grounds that the Ideas should exist; for man begets man, and the singular man begets a singular man. The same thing also holds true in the case of the arts; for the art of medicine is the formal determinant of health.
2441. Having stated his views about matter, the Philosopher now considers form, and in regard to this he does two things. First (1035:C 2440, he deals with form in itself; and second (1038:C 2446), with form in relation to the composite (“There are three kinds”).
In regard to the first part he does three things. First, he points out that form is a principle. He says that there are three causes, or three principles, of changeable substances. Two of these are contraries: one being “the specifying principle,” i.e., the form, the other privation, which is in a sense a contrary, and the third, matter. For it has been shown already (1029:C 2428-29) that in every change there must be a subject and two contraries, and therefore these are required in the generation of substance.
2442. It should be noted (1036).
Second, he shows that neither matter nor form is generated. He says that neither matter nor “form comes to be,” or is generated.—But this must be understood of the last matter and the last form; for some matter is generated, namely, the subject of alteration, since it is a composite substance.
2443. That neither the last matter nor the last form is generated he proves thus. In every change there must he some subject of the change, which is matter; and something by which it is changed, which is the principle imparting motion; and something to which it is changed, which is the specifying principle or form. Hence if both the form and the matter are generated, for example, if not only this whole—bronze sphere—is generated, but also the sphericity and the bronze, it follows that both form and matter have matter and form; and thus there will be an infinite regress in matters and forms. This is impossible. Hence, in the process of generation there must be some stopping point, so that the last matter and last form are not generated.
2444. Again, it should be (1037).
Third, he points out that things acquire their form from agents like themselves. He says that every substance comes to be “from an agent having the same name,” i.e., an agent similar in form. For all substances which are generated come to be either by nature or by art or by luck or “spontaneously,” namely, by chance; i.e., they are not directly an object of design. Art differs from nature, because art is a principle of action in something other than the thing moved, whereas nature is a principle of action and motion in the thing in which it is present. Now things produced by art obviously come to be from something similar to themselves in form; for it is by means of the form of the house in his mind that the builder causes the house which exists in matter. The same thing is also apparent in the case of natural things, for man begets man. However, this does not seem to be true in some cases, for some things are not generated by agents similar to themselves in species; for example, the heat found in lower bodies is generated by the sun, not by heat. Yet while there is no likeness in species, there must still be some kind of likeness, even though it is an imperfect one, because the matter of lower bodies cannot acquire perfect likeness to a higher agent. And since this is true in the case of things which come to be both by art and by nature, it is evident that each thing is generated by its like.
2445. For “the remaining causes,” luck and chance, are defects and privations as it were of nature and of art; for luck is intellect producing an effect over and above the one at which it aims; and chance is nature producing an effect over and above the one at which it aims. Hence those things which come to be by luck and by chance are not similar to their agents in form, since luck and chance are not causes in the strict sense but only accidentally. Therefore in a sense animals which are generated from decomposed matter seem to come into being by chance inasmuch as they are not generated by agents similar to themselves in species. Nor do they have a definite efficient cause in the realm of lower bodies, but only a higher efficient cause.
2446. There are three kinds (1038).
Then he establishes what is true of form in relation to the composite substance, and in regard to this he does three things. First, he divides substance into matter, form and composite. He says that there are three kinds of substance. First, according to appearances, matter seems to be substance and a determinate thing; and it was for this reason that the first natural philosophers claimed that matter alone is substance. They did this because they saw that in the case of artifacts, which come to be by contact and not by natural union, only the matter or underlying subject seems to be substance; for artificial forms are accidents. Second, the nature of a thing also seems to be substance and a determinate thing—the nature of a thing being that in which the process of natural generation is terminated, i.e., the form, which is as it were a kind of permanent state. The third kind of substance is the composite of matter and form, for example, singular things such as Callias and Socrates.
2447. Now in some cases (1039).
Second, he says that some forms evidently do not exist apart from the composite substance, for example, the form of a house does not exist apart from matter; for the form of a house is an accident, and the matter of a house is a substance, and an accident exists only in a substance.
2448. 1 say that this is true unless the form of the house should be taken “as the art,” i.e., as existing in the mind of the artisan, for in this way it does exist apart from matter. But there is neither generation nor destruction of these artificial forms as existing in the mind of the artisan; for the house which exists in the mind without matter, and health, and all things of this kind, begin to be and cease to be in a different way from those things which come to be by generation and destruction, i.e., by teaching or by discovery.
2449. But if any forms do exist apart from composite substances, this will be true of those natural forms which are substances. Hence Plato was not wrong in saying “that the Forms,” i.e., the separate Forms, are things which exist by nature. But I say that he was not wrong, not in an unqualified sense, but only if there are other forms which differ from sensible ones, such as flesh, head and the like, which are the last matter of a particular composite substance, which is substance in the fullest sense.
2450. Hence efficient causes (1040).
Third, he shows that there are no universal forms apart from composite substances. In regard to this he does two things. First, he makes his purpose clear by differentiating between formal and efficient causes. He says that efficient causes are prior to their effects; and this must be so because efficient causes are the source of the motion which terminates in the thing made. But the formal cause, which is a cause in the sense of the intelligible structure of a thing, begins to be when the thing of which it is the form begins to be. For health begins to be when a man is healed, and the shape of a bronze sphere begins to be when the bronze sphere comes into being. It is evident, then, that forms are not separate from composite substances; for if they were separate, they would have to be eternal, since of such things there is directly neither generation nor destruction, as has been shown (611:C 1420; 696:C 1687); and thus they would be prior to the substances of which they are the forms.
2451. But even though forms are not prior to composite substances, it is still necessary to investigate whether any form remains after the composite substance has been destroyed. For nothing prevents some forms from continuing to exist after the composite ceases to exist; for example, we might say that the soul is of this sort—not every soul but only the intellective. For perhaps it is impossible that every soul should be such that it continues to exist after the body has been destroyed, because the other parts of the soul do not operate without bodily organs, whereas the intellect does not operate by way of a bodily organ. He says “perhaps” because it is not his present intention to demonstrate this point; but this belongs to the science which treats of the soul. And just as the parts of the soul other than the intellect do not continue to exist after the composite substance has been destroyed, in a similar fashion neither do other forms of perishable things.
2452. Now we should observe that it is Aristotle’s view regarding the intellective soul that it did not exist before the body as Plato claimed, and also that it is not destroyed when the body is, as the ancient philosophers held inasmuch as they failed to distinguish between intellect and sense. For he did not exclude the intellective soul from the generality of other forms as regards their not existing prior to composite substances, but only as regards their not continuing to exist after the composite substances have been destroyed.
2453. From this consideration it is also evident that one cannot degrade the intellective soul as some men attempt to do, saying that the possible intellect alone or the agent intellect alone is imperishable. For these men claim not only that the intellect which they say is imperishable (whether it be the possible or the agent intellect) is a separate substance and thus not a form, but also that, if it is a form of the kind which remains after the body has perished, it must exist prior to the body. And in this respect there would be no difference between those who hold that a separate intellect is the form of man and those who hold that separate Forms are the forms of sensible things. This is the view which Aristotle aims to reject here.
2454. It is evident (1041).
Second, he rejects the argument by which they maintained that there are separate Ideas. For the Platonists said that it was necessary to posit Ideas in order that particular things might be formed in likeness to them. But this is not necessary, because in the realm of lower bodies one finds an adequate cause of the formation of everything that comes to be. For a natural agent produces something like itself. For man begets man; but it is not the universal man who begets a singular man, but the singular man begets a singular man. Hence it is not necessary to hold that there is a separate universal man by reason of which the singular man here receives, or shares in, the form of the species. The same thing is evident of those things which come to be by art, because the medical art is the formal determinant and likeness of health in the mind, as has also been shown above (1040:C 2450).
The Principles of Movable Substances
ARISTOTLE’S TEXT Chapters 4 & 5: 1070a 31-1071b 2
1042. In one sense the causes and principles of different things are different; but in another sense they are not, for, if one speaks universally and proportionally, they are the same for all.
1043. And one might raise the question whether the principles and elements of substances and of relations are the same or different; and the same question may be asked of each of the other categories.
1044. But it would be absurd if the principles and elements of all things were the same; for then substance and relations would be derived from the same principles. How then will this be [common]? For there is nothing common existing apart from substance and the other categories; and an element is prior to the things of which it is the element. But substance is not an element of relations, nor is any of these an element of substance.
1045. Further, how is it possible for the elements of all things to be the same? For none of the elements can be the same as a composite of elements; for example, neither b nor a is the same as ba; nor can any of the intelligibles, such as being and unity, be an element; for these belong to each composite thing. Hence none of them can be either a substance or a relation. But it must be one or the other. Therefore the elements of all things are not the same.
1046. Or, as we say, there is a sense in which they are the same and a sense in which they are not; for example, perhaps the elements of sensible bodies are the hot as form, the cold as privation, and that which primarily and of its own nature is potentially both of these as matter. And not only these are substances, but so also are the things of which they are the principles. And so also is any unity which comes to be from the hot and the cold, as flesh and bone; for the thing produced from these must differ from them. The elements and principles of these things, then, are the same, although the elements of different things are different. However, it cannot be said that the elements of all things are the same in this sense, but only proportionally, just as if one were to say that there are three principles, form, privation and matter. But each of these is different in each class of things; for example, in the case of colors there is white, black and surface; and there is darkness, light and air, from which day and night are derived.
1047. And since not only the things which are intrinsic to a being are its causes, but also certain external things, as the moving cause, it is evident that principle and element differ, although both are causes. And principle is divided into these two kinds; and whatever causes motion or makes it cease is a kind of principle. Hence analogically there are three elements and four causes or principles; but they differ in different things, and the first cause of motion is different in different things: for example, health, sickness and body, and the moving cause is the art of medicine. form, a certain kind of disorder, and bricks, and the moving cause is the art of building. Principle is also divided into these.
1048. And since in the case of physical things the moving cause of man is man, while in the case of objects of thought the moving cause is the form or its contrary, in one sense there will be three causes and in another sense four. For in a sense the art of medicine is health, and the art of building is the form of a house, and man begets man.
1049. And besides these there is that which as the first of all things imparts motion to all things.
1050. Since some things are separable and some are not, it is the former which are substances. And for this reason these (substances) are the causes of all things, because without substances there can be no affections and motions.
1051. Next, all of these causes are perhaps soul and body, or intellect, appetite and body.
11052. Again, there is another sense in which the principles of things are proportionally the same, i.e., as actuality and potentiality; but these are different for different things and apply to them in different ways. For in some cases the same thing is at one time actual and at another time potential, as wine, flesh or man. Now these principles fall into the classes of causes mentioned; for a form is an actuality if it can exist apart, and so also is the thing composed of matter and form, and so also is a privation, such as darkness and suffering; but matter is in potentiality, for it is what is capable of becoming both. But it is in another way that the distinction of actuality and potentiality applies to those things of which the matter is not the same, and the form is not the same but different. For example, the cause of man is his elements—fire and earth as matter, and his proper form—and if there is anything external, such as his father; and besides these there is the sun and the oblique circle, which are neither matter nor species nor privation nor form, but are moving causes.
1053. Further, we must note that some of these causes can be expressed universally and some. not. The first principles of all things are those first “this, one actually, one potentially. Therefore these principles are not universals, for the principle of a singular thing is a singular thing. For while man taken universally is a principle of man, there is no universal man, but Peleus is the cause of Achilles, and your father is the cause of you; and b and a taken either absolutely or particularly are the causes of the syllable ba. Further, there are different causes and elements of different things, as has been stated (1046), and the causes of things which do not belong to the same genus, as colors, sounds, substances and quantity, are different, except in a proportional way. And the causes of things which belong to the same species are different, not specifically, but in the sense that the causes of singular things are different; that is, your matter and form and moving cause are different from mine, although they are the same in their universal intelligibility.
1054. And to ask whether the principles and elements of substances and of relations and of qualities are the same or different, is clearly to raise questions about terms that are used in many senses. But the principles of different things are not the same but different, except that in a sense they are the same for all. They are the same for all proportionally because each thing has matter, form, privation and a moving cause. And the causes of substances may be regarded as the causes of all things because when they are destroyed all things are destroyed, And again that which is first in complete reality is the cause of all things. However, in a sense the primary [i.e., proximate] causes of things are different, i.e., all the contraries which are not predicated either as genera or as terms having many meanings. And again the matter of different things is different. We have stated what the principles of sensible things are, then, and how many there are, and how they are the same and how different.
2455. Having stated his position regarding the principles of sensible substances, the Philosopher’s aim here is to investigate whether the principles of substances and those of the other classes of things are the same or different. For if they are the same, it is evident that, when the principles of substances are given, the principles of all the other classes of things are also given. In regard to this be does three things. First (1042:C 2455), he states what is true. Second (1043:C 2456), he introduces a question relating to the answer proposed (“And one might”). Third (1054:C 2484), he gives a summary of what is true (“And to ask”).
He says, first, that in one sense the principles and causes of different things are different, and in another sense they are the same for all things, i.e., universally and proportionally.
2456. And one might (1043).
Then he examines the true answer given above, by raising a question; and in regard to this he does three things. First (1043:C 2456), he raises the question. Second (1044:C 2458), he argues on one side of the question (“But it would be”). Third (1046:C 2464), he settles the issue (“Or, as we say”).
He accordingly says, first (1043), that one might raise the question whether the principles of substances and those of relations, and also those of the other categories, are the same or different.
2457. He makes special reference to relations because they seem to be farther removed from substance than the rest of the categories are inasmuch as they have a more imperfect mode of being. And for this reason they inhere in substance by means of the other categories; for example, equal and unequal, double and half, inhere in substance by way of quantity; and mover and thing moved, father and son, master and slave, inhere in substance by way of action and passion. The reason is that, while substance is something which exists of itself, and quantity and quality are things which exist in something else, relations are things which not only exist in something else but also have being in reference to something else.
2458. But it would be (1044).
Then he argues on one side of the question mentioned above. He gives two arguments to show that the principles of substance and those of the other classes of things are not the same. The first argument is as follows. If the principles of substance and those of the other classes of things are the same, the same principles must either exist apart from substance and from the other categories, or they must belong to the category of substance or to some other category.
2459. But it cannot be said that they exist apart from substance and from the other categories, because then they would have to be prior both to substance and to the other categories; for a principle is prior to the things which come from it. Therefore, since what is prior is found to be more common, as animal is prior to man, it follows that, if some principle is prior both to substance and to the other categories, there must be some principle which is common both to substance and to the other categories. This applies especially to the opinion of the Platonists, who claimed that universals are principles—particularly being and unity as the most common principles of all things.
2460. Neither can it be said that the most common principles of all categories belong either to the category of substance or to that of relation or to any other category. For since principles are of the same kind as the things which come from them, it seems impossible that substance should be a principle of relations, or vice versa. Therefore the principles of substance and those of the other categories are not the same.
2461. Further, how is it (1045).
He gives a second argument, which runs thus: no element is the same as a composite of elements, for nothing is the cause or element of itself; for example, an element of this syllable ba is the letter b or the letter a.
2462. And since there would seem to be a rejoinder to this based on the principles laid down by Plato, namely, being and unity, since each thing composed of principles is one and a being, he therefore next rejects this argument. He says that it is also impossible that any of the intelligible elements—unity and being—should be the same as the things which are derived from them. He calls them intelligible, both because universals are grasped by the intellect, and because Plato claimed that they are separate from sensible things.
2463. He proves that elements of this kind differ from the things of which they are the elements, because “elements of this kind,” i.e., unity and being, are found in each of the things composed of them, whereas no one of the things composed of them is found in other things. Hence it is evident that these elements also differ from the things composed of them. If it is true, then, that elements are not the same as the things composed of them; and if the elements of substances and those of the other classes of things are the same, it follows that none of them belong either to the category of substance or to any other category. But this is impossible, because everything which exists must belong to some category. Hence it is impossible that all the categories should have the same principles.
2464. Or, as we say (1046).
Then he solves the question which was raised, and in regard to this he does two things. First (1046:C 2464), shows that the principles of all categories are proportionally the same; and second (1053:C 2482), that they are universally the same (“Further, we must note”). For he laid down these two qualifications above (1042:C 2455) when he said that there are the same first principles for all things universally and proportionally.
The first part is divided into two members inasmuch as he gives two ways in which the principles of all things are proportionally the same. He begins to treat the second (1052:C 2477) where he says, “Again, there is.”
In regard to the first he does two things. First, he shows how the principles of all things are proportionally the same. Second (1049:C 2474), he shows how they are the same without qualification (“And besides”).
In regard to the first he does two things. First, he shows that the principles of all things are proportionally the same as regards their intrinsic causes; and second (1047:C 2468), as regards both their intrinsic and their extrinsic causes (“And since not only”).
He accordingly says, first (1046), that in one respect it is true to say that the principles of all things are the same, and in another respect it is not.
2465. He explains this by saying that it would be the same as if we were to hold that the principle of sensible bodies in the line of specifying principle or form is the hot and in the line of privation is the cold, and that the matter of sensible bodies is what is of itself in potentiality to these two; for matter taken in itself is a principle that is susceptible both of form and of privation. He says “perhaps” because, while heat is not a substantial form of sensible bodies and cold is not a privation but both are qualities, still he uses them as form and privation in the category of substance in order to make the case more evident. Hence he adds that principles of this kind are substances, not as species in a genus, but as principles.
2466. Again, we say that things which are composed of these, i.e., the things of which these are the principles, namely, fire and water, are substances, granted that we understand fire to be composed of hot as a form and of its own matter, and water of cold as a privation and of matter; or again, granted that some one thing comes to be from the mixture of hot and cold, the above-mentioned contraries, hot and cold, and matter are the principles of these things; because that which comes to be from hot and cold must be something different from hot and cold, i.e., from the first bodies of which we imagine these to be the forms.
2467. Therefore the principles and elements of these things, i.e., of the simple bodies and the things composed of them, are the same. But other things have different proximate principles. However, the principles and elements of all these things are the same only proportionally. We might, for example, say that, just as the three things mentioned above—hot, cold, and their subject—have the character of form, privation and matter respectively in the generation of simple bodies, so too in every other genus there are three things which are proportioned to each other as form, privation and matter. But these three differ for different classes of things. For example, in the genus of color, white has the character of form, black the character of privation, and surface the character of matter or subject; and in the genus of distinctions of time, light has the character of form, darkness the character of privation, and air the character of matter or subject; and from these three principles day and night come to be.
2468. And since not only (1047).
Then he shows that the same thing is true of intrinsic and extrinsic causes, and in regard to this he does two things. First (1047:C 2468), he shows that, when we enumerate the intrinsic and extrinsic causes together, there are four causes proportionally of all things. Second (1048:C 2473), he shows how they are reduced to three (“And since in the case”).
He accordingly says, first (1047), that, since not only what is intrinsic is a cause, but also what is extrinsic, i.e., a mover, it is evident that principle and element differ. For principle in the strict sense means an extrinsic cause, as a mover, since it is from this that motion proceeds; whereas element in the strict sense means an intrinsic cause, of which a thing is composed.
2469. Yet both are called causes, i.e., both extrinsic principles and intrinsic ones. And in a sense principle is divided into these, i.e., into intrinsic causes and extrinsic causes. For there are certain intrinsic principles, as has been shown in Book V (403:C 755-56); for example, the foundation of a house is a principle of it in the sense of matter, and a soul is a principle of a man in the sense of form. But that which causes motion or makes it cease, i.e., which brings it to rest, is a principle but not an element; because an element is an intrinsic principle from which a thing comes to be, as has been stated in Book V (411:C 795-98).
2470. It is clear, then, that analogously, or proportionally, the elements of all things are three in numbermatter, form and privation. For privations are called elements not essentially but accidentally, i.e., because. the matter to which a privation is accidentally related is an element. For matter existing under one form contains within itself the privation of another form. But the causes and principles of things are four in number inasmuch as we may add the moving cause to the three elements. Aristotle does not mention the final cause, however, because a goal is a principle only inasmuch as it is present in the intention of the moving cause.
2471. Therefore the causes and principles of all things analogously are four in number—matter, form, privation, and the source of motion. Yet they are not the same in all cases, but differ in different things. For just as it has been said above (1046:C 2467) that matter form and privation differ in different things, so too the first of the causes, which has the character of a mover, differs in different cases.
2472. He clarifies this by giving examples. In the case of things healed, health has the character of form, sickness the character of privation, the body the character of matter, and the art of medicine the character of a mover; and in the case of things built, the shape of a house is the form, “a certain kind of disorder,” i.e., the opposite of the order which the house requires, is the privation, bricks are the matter, and the art of building is the mover. Principles, then, are divided into these four kinds.
2473. And since in the case (1048).
He now reduces these four kinds of causes to three on the ground that in the case of artifacts and in that of natural things the mover and the form are specifically the same. He accordingly says that this is clear because (a) in the case of natural things man is a mover inasmuch as he has a form; and (b) in the case of things which are made by mind or intellect the cause of motion is the form conceived by the mind, or even the contrary of the form through whose removal the form is induced. Therefore it is evident that in one sense there are three causes, inasmuch as the mover and the form are specifically the same, and in another sense there are four, inasmuch as these two causes differ numerically. For in a sense the art of medicine is health, and the art of building is the form of the house, i.e., inasmuch as the art itself is a kind of likeness and intelligible representation of the form which is in the matter. And similarly in the case of things which come to be through generation the generator is similar in form to the thing generated; for man begets man.
2474. And besides these (1049).
Then he shows that, although first principles are not identically the same beings in all things but only proportionally the same, none the less the first principles of all things are the same in an unqualified sense. He proves this by three arguments. First, he shows that the moving cause is the first of the causes which have been given because it is the one which makes the form or the privation exist in matter. Now in the class of movers it is possible to reach a single cause, as has been proved in Book VIII of the Physics. Therefore this first mover, which is one and the same for all, is the first principle of all things.
2475. Since some things (1050).
Second, he proves the same point in a different way. For some beings (substances) are capable of separate existence, and others (accidents) are not, because modifications and motions and accidents of this kind cannot exist apart from substances. It is evident, then, that the first principles in the category of substance are also the causes of all the other categories. This applies not only to the first moving cause but also to intrinsic causes; for the matter and form of a substance are the causes of its accidents.
2476. Next, all of these (1051).
Third, he shows that we must also reach certain first principles in the category of substance; for first principles in the category of substance are living animated substances according to the thought of Aristotle, who claimed that the celestial bodies are animated. Hence in the category of substance the first principles which have the character of form and matter will be soul and body, or also body and intellect or appetite; for assuming that a celestial body is animated, its soul has none of the different parts of the soul except intellect and appetite; for the other parts of the soul are directed to the preservation of bodies which are capable of being generated and destroyed. Intellect and appetite also have the character of a mover.
2477. Again, there is another sense (1052).
Then he gives a second way in which the principles of all things are proportionally the same. He says that the principles of all things are proportionally the same in another sense inasmuch as we say that actuality and potentiality are the principles of all things.
2478. But in this case two differences are to be observed. The first is that a different potentiality and a different actuality are principles in different things. The second is that potentiality and actuality are found in different things in different ways.
2479. Then the second difference is first clarified. He says that in some cases the same thing is at one time actual and at another time potential, as is evident of all things which admit of generation and destruction and are movable and contingent; for example, wine, flesh and man are at one time actual and at another potential. But some things are always actual, as the eternal substances.
2480. And since he had said that the way in which the principles of all things are proportionally the same differs from the one previously given, he next shows how these principles (actuality and potentiality) are reduced to the.same class. He says that these principles (actuality and potentiality) fall under the classes of causes mentioned above, which are form, privation, matter and mover; because form is an actuality, whether it is separable from the composite, as the Platonists claimed, or whether there is something composed of both, i.e., of form and matter. And similarly privation is in a sense an actuality, for example, darkness or “suffering,” i.e., sickness. But matter is in potentiality, because of itself it is capabie of receiving both form and privation. It is evident, then, that actuality and potentiality amount to the same thing as matter, form and privation; and that in a sense actuality and potentiality differ in different things, because they are not present in all things in the same way but in different ways.
2481. And since he had said that actuality and potentiality not only apply to different things in different ways but also differ for different things, he next explains this by saying that it is in a different way that the distinction of actuality and potentiality applies to different things of which the matter, which is in potentiality, is not the same, and the form, which is actuality, is not the same but different. For example, the material cause of a man is his elements, namely, fire and the like, and his formal cause is “his proper form,” i.e., his soul, and his moving cause is something extrinsic—his father being a proximate efficient cause, and the sun and “the oblique circle,” or zodiac, through which the sun moves together with the other planets which cause generation in lower bodies by their motion, being remote efficient causes. But extrinsic causes of this sort are neither matter nor form nor privation nor anything conforming to or specifically the same as these so that it could be said that they are reduced to these causes as actuality and potentiality. They are reduced to a different class of cause because they are movers, and these are also reduced to actuality. But things which differ from man have a different proper matter anA a different proper form and some proper agent.
2482. Further, we must note (1053).
Since it has been shown already (1046:C 2467) how the principles of all things are proportionally the same, Aristotle now wishes to show how the principles of all things are universally the same; for both of these points were mentioned above (1046:C 2464). He accordingly says that we must see how some principles are predicated universally and how some are not. The first principles which are understood to be most universal are actuality and potentiality, for these divide being as being. They are called universal principles because they are signified and understood in a universal way, but not so that universals themselves are subsisting principles, as the Platonists claimed, because the principle of each singular thing can only be a singular thing; for the principle of an effect taken universally is a universal, as man of man. But since there is no subsisting universal man, there will be no universal principle of universal man, but only this particular man will be the principle of this particular man; for example, Peleus is the father of Achilles, and your father is the father of you. And this particular letter b is a principle of this particular syllable ba, but b taken universally is a principle of ba taken universally. Therefore principles signified universally are the same for all things.
2483. Then he introduces a third way in which the principles of substances are universally the principles of all things, i.e., inasmuch as accidents are caused by substances. Now just as actuality and potentiality are the universal principles of all things because they flow from being as being, so also, to the extent that the community of things caused is lessened, the community of the principles must also be lessened. For things which do not belong to the same genus, as colors, sounds, substance and quantity, have different causes and elements, as has been pointed out (1046:C 2467), even though these are proportionally the same for all things. And things which belong to the same genus but are numerically different have different principles, not formally, but numerically. For example, your matter and form and moving cause are one thing and mine are another, but in their universal intelligibility they are the same; for soul and body are the form and matter of man, but this soul and this body are the form and the matter of this man.
2484. And to ask (1054).
Here he summarizes what has been said in this chapter. He says that to ask whether the principles and elements of substances and of relations and of qualities and of the other categories are the same or different is to raise questions about terms which are used in various senses, because the principles of different things are not the same except in a certain respect but different.
2485. For the principles of all things are the same in a certain respect, either proportionally, as when we say that in each class of things we find certain principles which have the character of matter, form, privation and moving cause; or in the sense that the causes of substances are the causes of all things, because when they are destroyed other things are destroyed; or because the principles are “complete reality,” i.e., actuality, and potentiality. The principles of all things, then, are the same in these three ways.
2486. But in another respect the principles are different, because contraries, which are principles of things, and matter itself are not predicated in the same way; for they are not genera, nor are they even predicated of things in many ways as though they were equivocal. Hence we cannot say that they are the same without qualification but only analogously.
2487. Last, he concludes by saying that he has shown the number of principles which sensible substances have and how they are the same or different.
An Eternal Immovable Substance Must Exist
ARISTOTLE’S TEXT Chapter 6: 1071b 3-1071b 22
1055. Since there are three classes of substance (1028), two of which are physical and one immovable, concerning the latter it is necessary to affirm that an eternal immovable substance must exist. For substances are the primary kind of beings, and if all of them are perishable, all things are perishable. But it is impossible either that motion should have come to be or that it should perish, for it always existed; and the same is true of time, for there cannot be a before and an after if there is no time. Motion is continuous, then, in the sense that time is; for time is either the same as motion or a property of it. Now the only continuous motion is that which pertains to place, and of this only that which is circular.
1056. But even if there is something which is capable of imparting or producing motion, but is not actually doing so, motion will still not exist; for that which has a potentiality may possibly not exercise it. Hence nothing is to be gained if we invent certain eternal substances, as do those who posit the separate Forms, unless there is some principle among them which is capable of causing change (83). This is not sufficient, then, nor is another substance besides the separate Forms sufficient; for if it does not act, there will be no eternal motion.
1057. And even if it does act this will still not be sufficient, if its essence is a potentiality; for there will be no eternal motion, since what is potential may possibly not be. Hence there must be a principle of the kind whose substance is an actuality.
1058. Further, such substances must also be immaterial; for they must be eternal if anything else is. Hence they are actualities.
2488. After having shown what the principles of sensible substances are, here the Philosopher begins to establish the truth about the immovable substances, which are separate from matter. This topic is divided into two parts. First (1055:C 2488), he treats substances of this sort by giving his own opinion. Second, he treats them by giving the opinions of other thinkers. He does this in the following book (“Concerning the substance of sensible things”).
The first part is divided into two members. First, he proves that there is a substance which is eternal, immovable and separate from matter. Second (1067:C 2519) he investigates the attributes of this substance (“Now the first mover”).
In regard to the first he does three things. First, he proves that an eternal substance must exist. Second (1059:C 2500), he deals with a question arising from the foregoing discussion (“There is a difficulty, however”); and third (1064:C 2508), from the answer given to the question which was raised he proceeds to clarify a truth previously ,established (“Hence, Chaos or Night”).
In regard to the first he does two things. First, he shows that it is necessary to posit an eternal substance. Second (1056:C 2492), he shows what kind of substance it must be (“But even if there is”).
He accordingly says, first (1055), that it has been pointed out above (1028:C 2424) that there are three classes of substances. Two of these are natural substances, because they undergo motion—one being eternal, as the heavens, and the other perishable, as plants and animals. And besides these there is a third class, which is immovable and not natural; and of this kind of substance it is now necessary to speak. With a view to investigating this kind of substance it is first necessary to prove that an eternal immovable substance must exist. He proceeds as follows.
2489. Substances are the primary kind of beings, as has been shown above (1024:C 2417-23), and when primary things are destroyed none of the others remain. Therefore, if no substance is eternal but all are perishable, it follows that nothing is eternal but that “all things are perishable,” i.e., they do not always exist. But this is impossible. Hence there must be an eternal substance.
2490. That it is impossible for nothing to be eternal he proves from the fact that motion cannot have come to be or “perish,” i.e., it cannot have come to be anew or at some time totally cease to be. For it has been shown in Book VIII of the Physics that motion is eternal without qualification. It also seems impossible that time should not be eternal; for if time began to be at some time or will cease to be at some time it would follow that prior to time there was the non-being of time, and also that there will be time after the non-being of time. But this seems to be impossible, because there could be no before or after if time did not exist, since time is nothing else than the measure of before and after in motion. Thus it would follow that time existed before it began to be, and that it will exist iifter it ceases to be. Hence it seems that time must be eternal.
2491. And if time is continuous and eternal, motion must be continuous and eternal, because motion and time are either the same thing, as some claimed, or time is a property of motion, as is really the case. For time is the measure of motion, as is evident in Book IV of the Physics. However, it must not be thought that every motion can be eternal and continuous, since this can be true only of local motion; and among local motions this is true only of circular motion, as is proved in Book VIII of the Physics.
2492. But even if (1056).
Then he shows what kind of substance this eternal substance must be, and in regard to this he does three things. First, he shows that in order to account for the eternity of motion it is necessary to posit an eternal sub~ stance which is always moving or acting. He says that, since it is necessary, on the assumption that motion is eternal, that there be an eternal substance which is capable of imparting or producing motion, it is also necessary that this be a mover or agent which is always acting, because if it were “capable of imparting or producing motion,” i.e., if it had the power to produce or cause motion, and was not actually doing so, it would follow that there would be no actual motion. For that which has the power of causing motion may possibly not be causing it, since that which has the power of acting may possibly not act; and thus motion would not be eternal. Assuming, then, that motion is eternal, it is necessary to posit an eternal substance which is actually moving or acting.
2493. Next, he concludes from this that nothing is to be gained by accepting the opinion of Plato, who posited eternal substances, since this is not sufficient to account for the eternity of motion. For the assumption that there are certain separate and eternal substances is not sufficient to account for this unless there is some principle among them which can ~ause change; but this does not seem to fit the separate Forms. For Plato claimed that the separate Forms are nothing else than universals existing apart from matter. But universals as such do not cause motion; for every active or motive principle is a singular thing, as has been pointed out above (1053:C 2482). Neither the separate Forms, then, nor any other separate substances besides the Forms, such as the separate mathematical entities posited by some, are sufficient to account for the eternity of motion, because even the objects of mathematics as such are not principles of motion. And if there is no eternal active substance, there will be no eternal motion, because the principle of motion is an eternal substance which is a mover or agent.
2494. And even if (1057).
Second, be shows that, in order for motion to be eternal it is necessary not only that an eternal substance exist, which is a mover or agent, but also that its essence be an actuality. Hence he says that the eternity of motion is not adequately accounted for even if it is supposed that an eternal substance does act yet is potential in essence. For example, it would not be sufficient to hold that the first principles are fire or water, as the ancient natural philosophers did, because then motion could not be eternal. For if a mover is such that its essence contains potentiality, it can possibly not be, because whatever is in potentiality may possibly not be. Hence it would be possible for motion not to be, and so it would not be necessary and eternal. Therefore it follows that there must be a first principle of motion of the sort whose essence is not in potentiality but is only an actuality.
2495. Further, such substances (1058).
Third, he further concludes that this kind of substance must be immaterial. He says that it also follows from the foregoing (1055-57:C 2488-94) that substances of this kind, which are the principles of eternal motion, must be free from matter; for matter is in potentiality. Therefore they must be eternal if something else is eternal, as motion and time. Thus it follows that they are actualities.
2496. He concludes in this way last because of the question which be will next raise. From this reasoning, then, it is evident that here Aristotle firmly thought and believed that motion must be eternal and also time; otherwise he would not have based his plan of investigating immaterial substances on this conviction.
2497. Yet it should be noted that the arguments which he introduces in Book VIII of the Physics, which he assumes as the basis of his procedure here, are not demonstrations in the strict sense but only dialectical arguments; unless perhaps they are arguments against the positions of the ancient natural philosophers regarding the beginning of motion, inasmuch as he aims to destroy these positions.
2498. And aside from the other arguments which he does not touch upon here, it is evident that the argument which he does give here to prove that time is eternal is not demonstrative. For if we suppose that at some moment time began to be, it is not necessary to assume a prior moment except in imaginary time; just as when we say that there is no body outside of the heavens what we mean by “outside” is merely an imaginary something. Hence, just as it is not necessary to posit some place outside of the heavens, even though “outside” seems to signify place, so too neither is it necessary that there be a time before time began to be or a time after time will cease to be, even though before and after signify time.
2499. But even if the arguments which prove that motion and time are eternal are not demonstrative and necessarily conclusive, still the things which are proved about the eternity and immateriality of the first substance necessarily follow; for, even if the world were not eternal, it would still have to be brought into being by something that has prior existence. And if this cause were not eternal, it too would have to be produced by something else. But since there cannot be an infinite series, as has been proved in Book II (153:C 301-4), it is necessary to posit an eternal substance whose essence contains no potentiality and is therefore immaterial.
Eternal Motion Requires An Eternal Mover
ARISTOTLE’S TEXT Chapters 6 & 7: 1071b 22-1072a 26
1059. There is a difficulty, however; for it seems that, while everything which is acting is able to act, not everything which is able to act is acting; so potentiality is prior.
1060. But if this is so, no beings will exist; for everything may be capable of being, but still not be. And if we take what the theologians say, who generate everything from Night, or what the— philosophers of nature say, who affirm that “all things were together,” they express the same impossible view. For how will things be moved, if there is no actual cause? Matter will not move itself, but technical knowledge will move it; nor will menstrual blood or earth move themselves, but semen or seed will move them.
1061. This is the reason why some men, such as Leucippus and Plato, posit something which is always actual; for they say that motion always exists. But they do not say why it exists, or what it is, or how this is so, or what its cause is. For nothing is moved by chance, but there must always be something existing which moves it. Now things are moved in one way by nature, and in another by force or by mind or by some other agent. What kind of motion, then, is prior? For this makes the greatest difference. Plato cannot explain what it is that he sometimes thinks is the source of motion, i.e., what moves itself; for according to him the soul is later than motion and simultaneous with the heavens.
1062. Now to think that potentiality is prior to actuality is in one sense right and in another not; and we have explained how this is so (1059).
1063. That actuality is prior is affirmed by Anaxagoras (for mind is an actuality), and by Empedolces in his theory of love and strife (50), and by those who say that motion always existed, as Plato and Leucippus.
1064. Hence Chaos or Night did not exist for an infinite time, but the same things have always existed, either in a cycle or in some other way, granted that actuality is prior to potentiality.
1065. Therefore, if something is always moved in the same cycle, there must be something which always continues to act in the same way. But if there is to be generation and destruction, there must be something else “ which acts in different ways. Hence this must act in one way of itself, and in another way in virtue of something else, i.e., either in virtue of some third agent or of the first. Now it must be in virtue of the first; for this is the cause both of the second and of the third. The first is preferable, then; for it was the cause of that whose being is always to be the same, and something else was the cause of that whose being is to be different; and obviously both of these account for eternal diversity. Therefore, if motion always exhibits these characteristics, why is it necessary to look for other principles?
And since this is a possible account of the matter, and if this is not so all things will come from Night (1060) or “all things were together” (1060) or something comes from non-being (1034), these difficulties are solved. And there is something which is always being moved with an unceasing motion, and this is circular motion. This is evident not only in theory but in fact; and for this reason the first heaven will be eternal.
1066. Therefore there is also something which causes it to move. And since that which is moved and causes motion is intermediate, there must be something which causes motion and is unmoved, which is eternal and both a substance and an actuality.
2500. He raises a question about a point already dealt with. The question is whether actuality is prior absolutely to potentiality so that the first principle of things can be held to be one whose substance is actuality. In regard to this he does three things. First (1059:C 2500), he gives an argument to show what is false, namely, that potentiality is prior absolutely to actuality. Second (1060:C 2501), he argues on the other side of the question (“But if this is so”). Third (1062:C 25o6), he answers the question (“Now to think”).
He accordingly says, first (1059), that it has been pointed out that an eternal substance is an actuality, although there is a difficulty regarding this. For potentiality seems to be prior to actuality, since one thing is prior to another when the sequence of their being cannot be reversed (465:C 950)Now potentiality seems to be related to actuality in this way, because everything which is acting seems to be able to act, but not everything which is able to act is acting; and so it seems that potentiality is prior to actuality.
2501. But if this is so (1060).
Then he argues on the opposite side of the question, and in regard to this he does two things. First, he gives an argument reducing the counter-position to absurdity. He says that, if potentiality is prior absolutely to actuality, it follows that at some time nothing may exist; for the contingent is what can come to be but has not yet done so. Hence, if the first beings are potential, it follows that they do not exist actually; and so no other being will exist.
2502. This can be taken in two ways. First, according to the opinion of certain of the ancients, who were called the theological poets, such as Orpheus and certain others, who claimed that the world “is generated from Night,” i.e., from a simple pre-existent privation. Second, according to the later physicists, i.e., philosophers of nature and their followers, who, when they saw that nothing comes from nothing in the natural world, claimed that all things were together in a kind of mixture, which they called Chaos. (Anaxagoras, for example, held this view.) Thus they held that all things exist potentially and not actually.
2503. But whether this position is stated in the former or in the latter way the same impossible conclusion follows, provided that potentiality is prior absolutely to actuality. For those things which are in potentiality only, or which come entirely under privation, or belong to some confused mass, cannot be moved so as to be brought to actuality unless there is some moving cause which is existing actually. For in things made by art the matter does not move itself, but an agent moves it, i.e., “technical knowledge,” or art. Neither does the menstrual blood, which is the matter from which an animal is generated, move itself, but “semen,” i.e., the sperm of the animal, moves it. Nor does earth, which is the material from which plants are generated, move itself, but “the seed,” i.e., the seeds of plants, move it.
2504. This is the reason (1061).
Second, he shows how some of the philosophers of nature agreed with this argument. He says that this is the reason why some philosophers—Leucippus, the companion of Democritus, and Plato—claimed that something actual always exists. For they said that motion had always existed even before the world; Leucippus attributed motion to the atoms, which are mobile of themselves, from which he supposed the world to be composed; and Plato attributed it to the elements, which he said were moved by disorderly motions before the formation of the world, and afterwards were brought into order by God.
2505. Now they seem to be right in claiming that motion has always existed. But they were wrong in failing to point out which kind of motion has always existed; nor did they give the cause of motion, either by stating this in an absolute sense or by giving the reason for their own position. Yet “nothing is moved by chance,” i.e., without some fixed cause, but there must always be something existing which is the cause of motion. For example, we now see that some things are moved in this way by nature or by force or by mind or by some other agent. Hence they should also have stated what the first cause of motion is, whether nature or force or mind; for it makes a great deal of difference which of these is held to be the cause of motion.—Plato cannot be excused on the ground that he held the principle of motion to be something that moves itself, which he asserted to be a soul, since the soul did not exist of itself before the formation of the world, but only existed after the disorderly state of motion. For according to him the soul was created at the same time as the heavens, which he claimed to be animated; and thus it could not be the principle of that disorderly motion.
2506. Now to think (1062).
Then he answers the question which was raised, and concerning this he does two things. First, he returns to the points established in Book IX regarding the relationship of potentiality to actuality. He says that the opinion that potentiality is prior to actuality is in one sense right and in another not. The sense in which it is right has been explained in Book IX (778-80:C 1844-49); for it was stated there that actuality is prior absolutely to potentiality. But in one and the same subject which is being moved from potentiality to actuality, potentiality is prior to actuality in time, although actuality is prior both in nature and in perfection.
2507. That actuality is prior (1063).
Second, he strengthens his answer by giving the opinions of some of the philosophers. He says that the absolute priority of actuality is asserted by Anaxagoras, because he claimed that the first principle of motion is an intellect; for intellect is a kind of actuality. The same thing is also asserted by Empedocles, who claimed that love and strife are the causes of motion; and also by Leucippus and Plato, who claimed that motion has always existed.
2508. Hence Chaos or Night (1064).
Then he uses the answer to the question given above to clarify a point previously established, and in regard to this he does three things. First (1064:C 25o8), in the light of the things established above he concludes that generation must be eternal. Second (1065:C 2510), on the ground that generation is eternal he concludes that the motion of the heavens must be eternal (“Therefore, if something”). Third (1066:C 2517), on the ground that the motion of the heavens is eternal he concludes that the first unmoved mover must be eternal (“Therefore there is”).
He accordingly says, first (1064), that, if actuality is prior absolutely to potentiality, it follows that it is false to hold, with the ancient philosophers of nature, who thought potentiality to be prior absolutely to actuality, that all things pre-existed potentially for an infinite time in a kind of confused mass, which they called Chaos. And false also is the opinion of the theological poets, who claimed for the same reason that the simple privation of things had existed for an infinite time before things began to be actually. Some called this privation of things “Night,” and perhaps the reason for their doing so is that among qualities and simple forms light is found to be more common and prior (since they thought that nothing exists except sensible things), and night is the privation of light. Both opinions are false, then, if actuality is prior to potentiality.
2509. But since we see that things which are generated and destroyed pass from potentiality to actuality, it will be necessary to say that the same things which begin to be actually after being potentially have always existed in some way. Either the very things which begin to be actually after being potentially have always existed according to circular generation, inasmuch as they claimed that things which are generated were formerly the same specifically but not numerically, and this is what occurs 2 in circular generation. For from the moist earth vapors are derived, and these turn into rain, by which the earth is again made moist. Similarly sperm comes from a man, and from sperm a man again comes to be. Thus things which come to be are brought back the same in species by reason of circular generation. Or again those things which come to be actually after being potentially have always been the same things in a different way, as Anaxagoras claimed that they had actual prior existence in the things from which they are generated.
2510. Therefore, if something (1065).
Then he concludes that the motion of the celestial bodies must be eternal on the ground that generation is eternal. Therefore, granted that there is no other motion by which things that pass from potentiality to actuality have always been the same except that which proceeds according to the cycle of generation, he concludes from what has been shown in the philosophy of nature (especially in Book II of Generation ) that, if something remains the same throughout the cycle of generation, something must also remain numerically the same, which will act in the same way so as to cause the eternal motion of things. For none of the things which are generated and destroyed can be the cause of the eternality which is found in generation and destruction, because no one of them always exists, nor even all of them, since they do not exist at the same time, as has been shown in Book VIII of the Physics. It follows, then, that there must be some eternal, agent which always acts in a uniform way so as to cause the eternal motion of things. This is the first heaven, which is moved and causes all things to be changed by its daily motion.
2511. But that which always acts in the same way only causes something that is always in the same state; and obviously those things which ~re generated and destroyed do not remain in the same state, for at one time they are generated and at another destroyed. This being so, if generation and destruction are to occur in the realm of lower bodies, it is necessary to posit some agent which is always in different states when it acts. He says that this agent is the body [the sun] which is moved in the oblique circle called the zodiac. For since this circle falls away on either side of the equinoctial circle, the body which is moved circularly through the zodiac must be at one time nearer and at another farther away; and by reason of its being near or far away it causes contraries. For we see that those things which are generated when the sun comes closer to the earth are destroyed when the sun recedes (for example, plants are born in the spring and wither away in the autumn); for both the sun and the other planets are moved in the circle of the zodiac. But the fixed stars are also said to be moved over the poles of the zodiac and not over the equinoctial poles, as Ptolemy proved. And the coming to be and ceasing to be of everything which is generated and destroyed is caused by the motion of these stars, but more evidently by the motion of the sun.
2512. Therefore this mover which acts in different ways must be one that “acts in one way of itself,” i.e., by its own power, inasmuch as it causes the diversity found in generation and destruction. And it must act “in another way in virtue of something else,” i.e., by the power of some other agent, inasmuch as it causes eternal generation and destruction. Hence this second agent must act either “in virtue of some third agent,” i.e., by the power of some other agent, “or of the first,” i.e., by the power of the first agent, which always acts in the same way. And since it is not possible to assign some other agent by whose power this first agent brings about the eternal motion of things, it is therefore necessary according to this “that it act in the same way”; that is, that by its power it causes the eternal generation and destruction of things. For it—the first agent—which always acts in the same way, is the cause of that which acts in different ways. For that which acts in different ways acts eternally, and that which acts in the same way is the cause of the eternality of any motion. Hence it is the cause of the eternality of that which acts in different ways inasmuch as the latter acts eternally in this way; and it is also the cause of that which is produced by it, namely, eternal generation and destruction. From this it is also evident that the second agent, which acts in different ways, acts by the power “of the first agent,” i.e., the first heaven or first orb, which always acts in the same way.
2513. Hence it is clear that the first agent, which always acts in the same way, is more powerful and nobler, because it is the cause of that “whose being is always to be the same,” i.e., of eternality. But the cause of that whose being is to be different is another agent, which acts in different ways. And it is evident that both of these combined, i.e., both the first agent, which always acts in the same way, and the second agent, which acts in different ways, are the cause of that which both always is and is in different states, namely, the fact that generation and destruction are eternal.
2514. Again, he concludes from this that, if the motions of the heavens are such that eternal generation and destruction in the realm of lower bodies can be caused by them, it is not necessary to look for any other principles (such as the Ideas, which the Platonists posited, or love and hate, which Empedocles posited), because it is possible to account for the eternal generation and destruction of things in the above way.
2515. And if this way is not accepted, the untenable conclusions to which the first philosophers were led will follow namely, that all things “will come from Night,” i.e., from a simple privation, or “all things were together,” or something comes from non-being.
296. Therefore it is evident that, if the above-mentioned position is accepted, i.e., that eternal generation and destruction are caused by the eternal motion of the heavens, the foregoing untenable conclusions are eliminated. And it will follow that something is always being moved in an unceasing motion, which is circular motion. This becomes apparent not only by reasoning but from the effect itself and by perception. Hence, since the first heaven always causes motion by means of this motion, it must be eternal.
2517. Therefore, there is (1066).
From what has been said above he next infers that there is an eternal unmoved mover. For since everything which is being moved is being moved by something else, as has been proved in the Physics, if both the heavens and their motion are eternal, there must be an eternal mover. But since three classes are found among movers and things moved: the lowest of which is something that is merely moved, the highest something that moves but is unmoved, and the intermediate something that both moves and is moved, we must assume that there is an eternal mover which is unmoved. For it has been proved in Book VIII of the Physics that, since there cannot be an infinite number of movers and things moved, we must come to some first unmoved mover. For even if one might come to something that moves itself, it would again be necessary for the above reason to come to some unmoved mover, as has been proved in that work.
2518. Again, if the first mover is eternal and unmoved, it must not be a potential being (because any potential being is naturally fitted to be moved) but an independent substance whose essence is actuality.—This is the conclusion which he drew above (1058:C 2499). But it was necessary to raise this question, which was discussed among the ancients, in order that when it has been solved the course to be followed in reaching a first being whose substance is actuality will be made more evident.
How the First Mover Causes Motion
ARISTOTLE’S TEXT Chapter 7: 1072a 26-1072b 14
1067. Now the first mover causes motion as something intelligible and something appetible; for these alone cause motion without being moved. And what is first in the class of the appetible and in that of the intelligible is the same; for it is the apparent good w1iich is the object of concupiscible appetite, and the real good which is the primary object of will. For we desire a thing because it seems good rather than consider it good because we desire it; for understanding is the principle of desire. And the intellect is moved by an intelligible object.
1068. And one of the two columns of opposites (60) is the intelligible in itself; and in this class primary substance is first, and in substance that which is simple and exists actually. However, one and simple are not the same; for one signifies a measure (432; 825), and simple signifies a state.
1069. But that which is good and that which is desirable in itself are in the same column of opposites; and that which is first in each class is always best, or analogous to the best. That the final cause belongs to the class of immovable things is shown by a process of division; for the final cause of a thing is either that which exists or that which does not.
1070. And it causes motion as something loved, whereas by that which is [first] moved other things are moved. Therefore, if a thing is moved, it is possible for it to be other than it. is. Hence, local motion, which is the primary kind of motion, is also the actuality of that which is [first] moved; and in this respect the thing first moved can differ in place though not in substance. But since there is something which moves yet is itself imm ovable and exists actually, this can in no way be other than it is. For the primary kind of change is local motion, and of local motion the first is circular motion; and this is the motion which the first mover causes. Hence the first mover necessarily exists; and insofar as it is necessary it is good, and thus is a principle. For necessary has all of these meanings: that which seems to be done by force; that without which something does not fare well; and that which cannot be other than it is, but is absolutely necessary (416-22). It is on such a principle, then, that the heavens and the natural world depend.
299. After having shown that there is an eternal, immaterial, immovable substance whose essence is actuality, the Philosopher now proceeds to investigate the attributes of this substance. In treating this he does three things. First (1061:C 2519), he considers the perfection of this substance. Second (1078:C 2553), he asks whether it is one or many (“We must not”). Third (1089:C 2600), he considers its operation (“The things which pertain”).
In regard to the first he does two things. First, he shows the perfection of this substance. Second (1076:C 2548), he proves that it is incorporeal (“And it has been shown”).
In regard to the first he does two things. First, he shows its perfection. Second (1075:C 2545), he rejects a contrary opinion (“And all those”).
In regard to the first he does two things. First, he explains how the unmoved mover causes motion; and second (1068:C 2523), he infers from this what is comprised in its perfection (“And one of the two”).
He accordingly says, first (1067), that, since it has been shown that the first mover is unmoved, it must cause motion in the way in which the desirable and the intelligible do; for only these, the desirable and the intelligible, are found to cause motion without being moved.
2520. He proves this as follows. Motion is twofold: natural and voluntary, or according to appetite. Now that which causes motion by means of natural motion necessarily undergoes motion, since a natural mover is one that begets and alters things. For both heavy and light bodies are moved locally directly by their begetter. But that which begets and alters things directly must exist in different states. Hence it has also been pointed out above (1065:C 2510) that the cause of generation and destruction acts in different ways. Now in the case of voluntary and appetitive motion, will and appetite have the character of moved movers, as is evident in Book III of The Soul. Hence it remains that only that which causes motion as something appetible is an unmoved mover.
2521. Now it is said that the first mover causes motion as something appetible because the motion of the heavens has this mover as its end or goal, for this motion is caused by some proximate mover which moves on account of the first unmoved mover in order that it may be assimilated in its causality to the first mover and bring to actuality whatever is virtually contained in it. For the motion of the heavens does not have the generation and destruction of lower bodies as its end, since an end or goal is nobler than the things ordained to it. Therefore the first mover causes motion as something appetible.
2522. But in our own case that which causes motion as a desirable good differs from that which causes motion as an intelligible good, though each causes motion as an unmoved mover. This is particularly evident in the case of an incontinent person; for according to his reason he is moved by an intelligible good, but according to his concupiscible power he is moved by something pleasant to the senses, which, while it seems to be good, is not good absolutely but only with some qualification.—However, this kind of difference cannot be found in the first intelligible and the first desirable good. But the first intelligible and the first desirable good must be the same. The reason is that a concupiscible good, which is not an intelligible good, is merely an apparent good; but the first good “must be an object of will,” i.e., an object desired by intellectual appetite. For will belongs to the intellectual order and not merely to that of concupiscible appetite. And this is so because what is desired by the concupiscible power seems to be good because it is desired; for concupiscence perverts the judgment of reason insofar as something pleasant to sense seems to be good to reason. But what is desired by intellectual appetite is desired because it seems to be good in itself. For “understanding” as such, i.e., the act of intellection, which is moved in a way by an intelligible object, “is the principle of desire.” Therefore it is evident that the object of concupiscible appetite is good only when it is desired through a dictate of reason. Hence it cannot be the first good, but only that which, because it is good, moves desire and is at once both appetible and intelligible.
2523. And one of the two (1068).
Since he has proved that the first mover is both intelligible and appetible, it now remains to show from this how perfection is found in the first mover. In regard to thi8 he does three things. First (1068:C 2523), he shows the perfection of the first mover in itself by considering the formal character of the intelligible and the appetible; second (1070:C 2529), in relation to the first sphere (“And it causes motion”); and third (107:C 2536), in relation to the thing that desires and understands it (“And its course of life”).
In treating the first part he does two things. First, he proves that the first mover is perfect on the ground that it is intelligible; and second (106g:C 2526), on the ground that it is appetible (“But that which is good”).
He says, first (1068), that, just as movers and things moved are related to one another, so also are intelligible things. He calls this latter relationship an intelligible column of opposites because one intelligible is the first principle for understanding another, just as one mover is also the cause of the motion of another.
2524. Therefore, just as it has been shown (1066:C 298) from the series of movers and things moved that the first mover is a simple substance and an actuality, in a similar fashion the same thing is found to be true from the series of intelligible things. For it is evident that substance is the first of intelligible things, because we understand accidents only by means of substance, through which they are defined; and among substances a simple intelligible substance is prior to a composite one; for simple things are included in the concept of composite things. And of the simple entities contained in the class of substance the actually intelligible are prior to the potentially intelligible; for potentiality is defined by means of actuality. It follows, then, that the first intelligible entity is a simple substance which is an actuality.
2525. And lest he should seem to be adopting the opinion of Plato, who claimed that the first principle of things is the intelligible one-in-itself, he therefore explains the difference between being one and being simple. He says that one and simple do not signify the same thing, but one signifies a measure, as has been pointed out in Book X (825:C 1950-52), and simple signifies that state whereby something is such as not to be composed of many things.
2526. But that which is good (1069).
Then he proves the same point from the formal character of the appetible. He says that that which is good and that which is desirable in itself belong to the same class. For that which is prior in the class of intelligible things is also a greater good in the class of appetible things, or is something analogous to it. He says this because intelligible things are actual insofar as they exist in the intellect, whereas appetible things are actual insofar as they exist in reality; for good and evil are in things, as has been pointed out in Book VI (558:C 1240).
2527. Hence, just as the concept of intelligible substance is prior to that of intelligible accidents, the same relationship holds for the goods which correspond proportionally to these concepts. Therefore the greatest good will be a simple substance, which is an actuality, because it is the first of intelligible things. It is evident, then, that the first mover is identical with the first intelligible and the first appetible good, which is the greatest good.
2528. But since what is appetible and what is good have the character of an end or goal, and there does not seem to be an end in the realm of immovable things, as has been explained in the dialectical discussions in Book III (192:C 374-75), he therefore removes this difficulty. He says that the division in which the various senses of end or goal are distinguished shows that a final cause can be found in a way in the realm of immovable things. Now one thing can be the goal of another in two ways: first, as something having prior existence, as the center of the world is said to be a goal which is prior to the motion of heavy bodies; and nothing prevents a goal of this kind from existing in the realm of immovable things. For a thing can tend by its motion to participate in some degree in something immovable; and the first mover can be a goal in this way. Second, one thing is said to be the goal of another, not as something that exists actually, but only as existing in the intention of the agent by whose activity it is produced, is health is the goal of the activity of the medical art. An end or goal of this kind does not exist in the realm of immovable things.
2529. And it causes motion (1070).
He now relates the first unmoved mover to the first sphere. He says that, since the first unmoved mover causes motion as something loved, there must be something which is first moved by it, through which it moves other things. This is the first heaven. Therefore, since we suppose motion to be eternal, the first sphere must be moved eternally, and it in turn must move other things. And it is better to speak of it as something loved rather than as something desired, since there is desire only of something that is not yet possessed, but there is love even of something that is possessed.
2530. And if it must be moved eternally, it must be incapable of being other than it is but must always remain substantially the same. Hence the primary kind of motion, by which “the first sphere” is moved, necessarily “is local motion,” i.e., motion as regards place; because that which is moved “according to the other kinds of motion,” i.e., generation and destruction, increase and decrease, and alteration, must differ as regards something intrinsic, namely, substance, quantity or quality. But that which is moved with local motion differs as regards place, which is extrinsic to the thing in place, but not as regards substance or any intrinsic disposition of substance.
2531. Therefore, since the first sphere differs as regards place but not as regards substance, the first mover, which is immovable and always actual, can in no way be other than it is, because it cannot be moved. For if it were moved, it would be moved especially with the primary kind of motion, which is local motion, of which the first type is circular. But it is not moved with this motion, since it moves other things with this motion. For the first mover is not moved with that kind of motion by which it imparts motion, just as the first cause of alteration is not itself altered. Hence it is not moved circularly, and so cannot be moved in any way. Therefore it cannot be other than it is; and thus it follows that the primary kind of motion exists in that which is moved of necessity; for that is necessary which cannot not be. But it is not necessary in the sense in which things forced are necessary, but its necessity consists in its good state. And the thing which moves it is a principle of motion as an object of desire, or a goal.
2532. That its necessity is such becomes evident from the different meanings of the term necessary, for it is used in three senses. First it means that which happens by force, i.e., what cannot fail to happen because of the power exerted by the thing applying force. Second, it means that without which a thing does not fare well—either that without which a goal cannot be attained at all (as food is necessary for the life of an animal), or that without which something is not in a perfect state (as a horse is necessary for a journey in the sense that it is not easy to make a journey without one). Third, it means that which cannot be other than it is, but is necessary absolutely and essentially.
2533. Therefore, when it is said that an orb is moved of necessity, such necessity cannot be called necessity of force; for in imperishable things there is not found anything that is outside their nature, but in the case of things which are forced what occurs is not natural. Similarly such necessity cannot be absolute necessity, because the first thing which is moved moves itself, as is proved in Book VIII of the Physics, and what moves itself has within itself the power to move or not move. It follows, then, that the necessity of the first motion is necessity from the end, inasmuch as there cannot be a fitting order to the end unless such motion is eternal.
2534. Hence it is on this principle, i.e., the first mover viewed as an end, that the heavens depend both for the eternality of their substance and the eternality of their motion. Consequently the whole of nature depends on such a principle, because all natural things depend on the heavens and on such motion as they possess.
2535. It should also be noted that Aristotle says here that the necessity of the first motion is not absolute necessity but necessity from the end, and the end is the principle which he later calls God inasmuch as things are assimilated to God through motion. Now assimilation to a being that wills and understands (as he shows God to be) is in the line of will and understanding, just as things made by art are assimilated to the artist inasmuch as his will is fulfilled in them. This being so, it follows that the necessity of the first motion is totally subject to the will of God.
The Perfection of the First Substance
ARISTOTLE’S TEXT Chapter 7: 1072b 14-1073a 13
1071. And its course of life is like the best which we enjoy for a short time; for it is always in that state, though this is impossible for us.
1072. For its operation is also pleasure. This is why being awake, sensing and understanding are most pleasant, and hopes and memories are pleasant because of them. Now understanding in itself has to do with what is best in itself, and the highest type of understanding has to do with what is best in the highest degree.
1073. And an intellect understands itself insofar as it takes on its intelligible object; for it becomes intelligible by attaining and understanding its object, so that an intellect and its intelligible object are the same. For that which is receptive of something intelligible and of substance is an intellect; and it is actual when it possesses this. Hence it is the latter rather than the former state which seems to constitute the divine state of intellect; and its act of understanding is the most pleasant and best. Therefore, if God is in that pleasurable state in which we sometimes are, this is wondrous; and if He is in that state in a higher degree, this is even more wondrous; and He is in that state.
1074. Life, then, also belongs to Him; for intellectual activity is life, and God is that activity; and the essential activity of God is the life which is best and eternal. And we say that God is an animal, eternal and most excellent. Hence life and continuous and eternal duration belong to God; for this is what God is.
1075. And all those, such as the Pythagoreans and Speusippus, who think (1109:C 2644) that the greatest good and excellence are not found in the [first] principle (because they are of the opinion that, while the principles of plants and animals are causes, it is in the things that come from these that goodness and perfection are found) are in error. For seed comes from other things which are prior and perfect, and it is not seed that is first but the perfect being. For example, one might say that the man is prior to the seed, not the man who comes from the. seed, but another man from whom the seed comes (780). Therefore it is evident from what has been said that there is a substance which is eternal and immovable and separate from sensible things.
1076. And it has been shown that this substance can have no magnitude, but is without parts and indivisible; for it causes motion for an infinite time, and nothing finite has an infinite power. And since every magnitude is either finite or infinite, this substance cannot have finite magnitude; and it cannot have infinite magnitude, because there is no infinite magnitude at all.
1077. It has also been shown (1066) that it lacks potentiality and is unalterable; for all the other kinds of motion are subsequent to local motion. It is clear, then, that these things are of this sort.
2536. Here the Philosopher relates the first being, which causes Motion as something intelligible and something desirable, to that which understands and desires it. For if the first mover causes motion inasmuch as it is the first thing understood and desired, the first thing moved by it must understand and desire it. This is true according to the opinion of Aristotle inasmuch as he considered a heaven to be animated by a soul which understands and desires.
In regard to this he does three things. First (1071:C 2536), he shows that pleasure naturally belongs to the soul of a heaven, which desires and understands, as a result of its understanding and desiring the first mover. He says that “its course of life,” i.e., the pleasurable state of the thing understanding and desiring the first intelligible being, is like the best which we can enjoy for a short time. For that which understands and desires this being is always in such a pleasurable state, though this is impossible for us, i.e., that we should always be in that state which is pleasant and best.
2537. For its operation (1072).
Then he proves his statement. Pleasure attends the activity of the thing that understands and desires the first principle, for pleasure follows upon the operation connatural to anything that understands and desires, as is evident in Book X of the Ethics. A sign of this is that pleasure is greatest when a person is awake and actually sensing and understanding. For intellect and sense in actual use are to intellect and sense in potential use as being awake is to being asleep.—That these states are the most pleasant is clear from the fact that other states are pleasant only because of these; for hope and memory are pleasant inasmuch as they bring past or future pleasant activities into consciousness as present.
2538. Hence, since pleasure consists in the actual use of intellect and sense, it is evident “that understanding,” i.e., the activity of the intellect as such, is concerned with what is best in itself; for an intelligible good surpasses a sensible good just as an unchangeable and universal good surpasses a changeable and particular good. It also follows that the pleasure experienced in intellectual activity is of a higher kind than that experienced in sensory activity. Hence the best and most perfect intellectual activity is concerned with what is best in the highest degree, so that the greatest pleasure follows. Therefore it is evident that the greatest pleasure is experienced in those intellectual activities by which the first mover is understood, who is also the first intelligible object.
2539. And an intellect (1073).
Then he shows that the act of understanding and the pleasure found in the first intelligible object are even more perfect than those found in the thing that understands and desires it. He says that it is characteristic of an intellect to understand itself inasmuch as it takes on or conceives within itself some intelligible object; for an intellect becomes intelligible by reason of the fact that it apprehends something intelligible. Hence, since the intellect becomes intelligible by conceiving some intelligible object, it follows that the intellect and its intelligible object are the same.
2540. He explains how an intellect attains its intelligible object. For an intellect is related to an intelligible object as potentiality is to actuality, and as something perfectible to its perfection. And just as something perfectible is receptive of a perfection, so too an intellect is receptive of its intelligible object. Now its proper intelligible object is substance, since the object of the intellect is a quiddity. Hence he says that the intellect is receptive of something intelligible and of substance. And since each thing becomes actual inasmuch as it attains its own perfection, it follows that the intellect becomes actual inasmuch as it receives its intelligible object. Now to be intelligible is to be actual in the class of intelligible things. And since each thing is active to the extent that it is actual, it follows that the intellect becomes active or operative, i.e., understanding, to the extent that it attains its intelligible object.
2541. But it should be borne in mind that material substances are not actually intelligible but only potentially; and they become actually intelligible by reason of the fact that the likenesses of them which are gotten by way of the sensory powers are made immaterial by the agent intellect. And these likenesses are not substances but certain intelligible forms received into the possible intellect. But according to Plato the intelligible forms of material things are self-subsistent entities. Hence he claimed that our intellect becomes actually understanding by coming in contact with separate self-subsistent forms of this kind. But in Aristotle’s opinion the intelligible forms of material things are not substances which subsist of themselves.
2542. Yet there is an intelligible substance which subsists of itself, and it is of this that he is now speaking. For the first mover must be a substance which is both understanding and intelligible. Hence it follows that the relationship between the intellect of the first sphere and the first intelligible substance, which causes motion, is similar to the relationship which the Platonists posited between our intellect and the separate intelligible Forms, inasmuch as our intellect becomes actual by coming in contact with and participating in these Formi, as Plato himself says. Hence the intellect of the first sphere becomes actually understanding through some kind of contact with the first intelligible substance.
2543. Further, since the cause of some attribute of a thing has that attribute in a higher degree, it follows that anything that is divine and noble, such as understanding and taking pleasure, which is found in the intellect having the contact, is found in a much higher degree in the first intelligible object with which it is in contact. Hence its intellectual activity is most pleasant and best. But the first intelligible object of this kind is God. Therefore, since the pleasure which we experience in understanding is the highest, although we can enjoy it only for a short time, if God is always in that state in which we sometimes are, His happiness is wondrous. But if He is always in that state (which we enjoy for only a short time) in a higher degree, this is even more wondrous.
2544. Life, then, also belongs (1074).
Third, since he has said that intellectual activity is proper to God, he shows how this applies to Him. He says that God is life itself, and he proves this as follows. “Intellectual activity,” i.e., understanding, is a kind of life; and it is the most perfect kind of life that there is. For according to what has been shown, actuality is more perfect than potentiality; and therefore an intellect which is actually understanding leads a more perfect life than one which is potentially understanding, just as being awake is more perfect than being asleep. But the first being, God, is actuality itself; for His intellect is His intellectual activity; otherwise He would be related to His intellectual activity as potentiality to actuality. Moreover, it has been shown (1066:C 2517) that His substance is actuality. Thus it follows that the very substance of God is life, and that His actuality is His life, and that it is the life which is best and eternal and subsists of itself. This is why common opinion holds that God is an animal which is eternal and best; for around us life is clearly apparent only in animals, and therefore God is called an animal because life belongs to Him. Hence, from what has been said it is evident that life and continuous and eternal duration belong to God, because God is identical with His own eternal life; for He and His life are not different.
2545. And all those (1075).
Then he rejects the opinion of those who attributed imperfection to the first principle. He says that the opinion of all those who claim that goodness and excellence are not found in the first principle are false. He cites as examples the Pythagoreans and Speusippus (1109:C 2644), who acted on the supposition that, while the principles of plants and animals are causes of goodness and perfection, goodness and perfection are not found in these principles but in the things produced from them. Thus seeds, which are imperfect principles of plants and animals, come from other individual things which are prior and perfect.
2546. He rejects this opinion by disposing of the view which influenced these thinkers. For it is not seed that is first absolutely, but the perfect being. Hence, if someone says that the man is prior to the seed, it is not the man who is said to be born from the seed in question, but a different man from whom the seed comes. For it has been proved above (1059-60:C 2500-03) that actuality is prior absolutely to potentiality, though in one and the same subject potentiality is prior to actuality in the order of generation and of time.
2547. In view of the points established he terminates his discussion by concluding that it is evident that there is a substance which is eternal and unchangeable and separate from sensible things.
2548. And it has been shown (1076).
Then he proceeds to examine certain points which still remain to be considered about the above-mentioned substance. First, he shows that it is incorporeal. He says that it has been proved in Book VIII of the Physics that this kind of substance can have no magnitude but is without parts and indivisible.
2549. He briefly restates the proof, saying that a substance of this kind moves in infinite time, since the first mover is eternal, as he said above (1075:C 2547). And from this it follows that its power is infinite. For we see that the more powerful any inferior mover is, the more capable it is of acting for a longer time. But nothing finite can have an infinite power. Hence it follows that the above-mentioned substance is not finite in magnitude. Moreover, it cannot be infinite in magnitude because an infinite magnitude is impossible, as has been proved above (1076:C 2548). Therefore, since every magnitude is either finite or infinite, it follows that the above-mentioned substance lacks magnitude in every way.
2550. Moreover, the power of this substance is not said to be infinite in a privative sense, in the way that infinity pertains to quantity; but the term is used in a negative sense, i.e., inasmuch as it is not limited to some definite effect. It cannot be said of a heavenly body, however, that its power is infinite even though it may move inferior bodies in an infinite time, because it causes motion only by being moved, and thus its influence is from the first mover. Nor can it be said that the power of a heavenly body is infinite even though it has being in infinite time, because it has no active power of being but only the ability to receive. Hence its infinite duration points to the infinite power of an external principle. But in order to receive indestructible existence from an infinite power a heavenly body must not have any principle of destruction or any potentiality to non-existence.
2551. It has also been shown (1077).
Second, since he has shown above (1066:C 2517) that the first mover is not moved with local motion, he next shows that it is not moved with the other kinds of motion. He says that it is also impossible for the first mover to be alterable, for it has been shown above (1066:C 2517) that it is not moved with local motion. But all other motions are subsequent to such motion, which pertains to place. Therefore, when the former is removed, so also must the latter be. Hence whatever is found to be moved with the other kinds of motion is moved with local motion.
2552. Last, he concludes that the things discussed above are evidently such as he has established them to be.
The Number of Primary Movers
ARISTOTLE’S TEXT Chapter 8: 1073a 14-1073b 17
1078. We must not neglect the question whether it is necessary to posit one such substance or more than one, and if the latter, how many; and we must also recall the lack of statements on this point by other philosophers, because they have said nothing about the number of these substances which can be clearly stated. The theory of Ideas makes no proper study of this problem; for the proponents of the Ideas say that the Ideas are numbers, and they speak of numbers sometimes as unlimited and sometimes as limited to the number ten. But as to the reason why there should be so many numbers, nothing is said apodictically.
1079. However, we must discuss this question by beginning with what has already been laid down and established. For the first principle and primary being is both essentially and accidentally immovable, but it causes the primary motion, which is eternal and unique. And since that which is moved must be moved by something else, the first mover must be essentially immovable, and eternal motion must be caused by an eternal mover, and a single motion by a single thing.
io8o. Now we see that, besides the simple local motion which we say the first immovable substance causes, there are other local motions—those of the planets—which are eternal (for a body which is moved in a circle is eternal and never stands still, as has been proved in our treatises on nature) . Each of these motions, then, must also be caused by a substance which is essentially immovable and eternal. For the nature of the stars is eternal, being a kind of substance; and that which causes motion is eternal and prior to that which is moved; and that which is prior to a substance must be a substance. Hence it is evident that there must be as many substances as there are motions of the stars, and that these substances are eternal in nature, essentially immovable, and without magnitude, for the reason given above (1076). It is evident, then, that these movers are substances, and that one of these is first and another second according to the same order as the motions of the stars.
1081. But it is now necessary to discover the number of these motions from that branch of the mathematical sciences which is most akin to philosophy, namely, astronomy. For this science studies the kind of substance which is sensible but eternal, whereas the other mathematical sciences, such as the science of numbers and geometry, are not concerned with any kind of substance. That there are many motions belonging to the bodies which are moved is evident even to those who have given little consideration to the matter; for each of the wandering stars has more than one motion. As to the number of these motions, in order that we may have some definite number in mind for the purpose of understanding this point, let us now state what some of the mathematicians say; but for the rest, this we must investigate partly for ourselves and partly accept the opinion of other investigators. And if anyone in treating this subject should be found to form a different opinion from the one stated here, we must respect both views but accept the more certain.
2553. Having shown what it is that constitutes the perfection of an immaterial substance, here the Philosopher asks whether this substance is one or many; and in regard to this he does three things. First (1078:C 2553), he indicates that it is necessary to treat this question because nothing definite has teen said about it by other thinkers. Second (1079:C 2555), he shows that there are many such substances (“However, we must discuss”). Third (1081:C 2563), he shows how many there are (“But it is now necessary”).
He accordingly says, first (1078), that we must not neglect the question whether it is necessary to posit only one such substance which is eternal and immaterial or many; and if the latter, how many. But we must also “recall the lack of statements on this point by other philosophers,” i.e., the fact that others have said nothing that is clear and evident about the number of these substances.
2554. This is made clear as follows. Those who made a special claim for immaterial substances were the proponents of the Ideas. Now the opinion about the nature of the Ideas contains no theory about any definite number, because there are assumed to be Ideas of all things which share in a common name. But since those who posited Ideas said that they are numbers, it would seem that we could get some notion about how many numbers there are. However, they did not always say the same thing on this point. Sometimes they said that the species of numbers are unlimited. This is true of numbers by reason of their proper nature, because whenever a unit is added it always produces a different species of number. Hence, since in the case of numbers infinite additions can be made, the species of numbers may increase to infinity. At other times they said that the species of numbers are limited to the number ten. This refers to the naming of numbers, for the names of all numbers after ten seem to repeat in some way the name of a primary number. But they cannot show by any definite argument why there should be just so many numbers, i.e., ten, and not more or fewer. Nor is this to be wondered at, since this limitation of the species of numbers is not a real limitation but a nominal one. Other thinkers offer the argument that the number ten is generated from the progression of numbers up to the number four, which is the first square number. For one plus two equals three; and when three is added to this, the number six results; and when four is added to this, the number ten results.
2555. However, we must discuss (1079).
He now shows that there must be many substances of this kind; and in regard to this he does two things. First, he returns to the points established about the first principle. He says that, since other thinkers have said nothing demonstrative about the number of separate substances, we must discuss this question by beginning with what has already been laid down and established. For it has been said above that, while the first principle of beings is one which is neither essentially nor accidentally moved, it still causes a single motion, which is the first and eternal motion. For since everything which is moved must be moved by something else, as has been shown in Book VIII of the Physics, the first mover must be altogether immovable, and eternal motion must be caused by an eternal mover, and a single motion by a single mover.
2556. Now we see (1080).
Second, he shows that after the first principle it is necessary to posit a number of eternal substances. He says that besides the simple local motion of the universe (one that lasts a day —during which the entire heavens revolve—and is uniform and the most simple), which the first immovable substance causes, we observe the local motions of the planets, which are also eternal; because the circular body, i.e., a heaven, is also eternal. Therefore the eternity of motion is no; destroyed as a result of the destruction of a movable being. And “it never stands still,” i.e., it is incapable of coming to rest. Hence this motion is not broken by rest. These points have been proved in the philosophy of nature, both in the Physics as well as in The Heavens. Each of these motions, then, must be caused by a mover which is essentially unmoved and an eternal substance.
2557. Now this must be so because the stars are eternal and are substances. Hence their mover must also be eternal and a substance; for a mover is prior to the thing moved, and that which is prior to a substance must be a substance. It is clear, then, that there must be as many substances as there are motions of the stars, and that these substances must be by nature eternal and essentially immovable and without magnitude, for the reason given above (1076:C 2548-50), i.e., because they move in infinite time and therefore have infinite power. Hence it is evident that there are immaterial substances which are as numerous as the motions of the stars, and that they also have the same order as the motions of the stars.
2558. Now it must be borne in mind that after the first motion Aristotle computes only the motions of the planets, because at his time the motion of the fixed stars had not been detected. Hence he thought that the eighth sphere, in which the fixed stars are located, was the first one to be moved, and that its mover was the first principle. But later on astronomers perceived that the motion of the fixed stars was in an opposite direction to the first motion, so that above the sphere of the fixed stars it was necessary to posit another sphere, [This “ninth” orb or sphere of which St. Thomas speaks was postulated by the astronomers in order to account for the motion which the celestial pole was discovered to be describing every 36,ooo years. Since it encompassed all the other spheres, it was considered to be a ninth or outermost sphere, and therefore the first in order of all the spheres.] which surrounds the entire heavens and turns the whole in its daily motion. This is the first sphere, which is moved by the first mover of which Aristotle spoke.
2559. But Avicenna claimed that the first sphere is moved directly, not by the first principle, but by an intelligence which is caused by the first principle. For since the first mover is absolutely one, Avicenna thought that only one thing could be caused by it; and this is the first intelligence, in which a plurality of potentiality and actuality is found inasmuch as it derives being from the first principle. For it is related to that on which it depends for its existence as something potential to something actual. Hence the first intelligence can immediately cause many things; for inasmuch as it understands itself as having some potentiality, it causes the substance of the orb which it moves, but insofar as it understands itself as possessing actual existence from some other cause, it causes the soul of its orb. Again, inasmuch as it understands its own principle, it causes the next intelligence, which moves a lower orb, and so on down to the sphere of the moon.
2560. But this is not necessary. For an efficient cause in the realm of superior substances does not act like an Acient cause in the realm of material things, in the sense that a single effect is produced by a single cause, because among higher substances cause and thing caused have intelligible existence. Hence insofar as many things can be understood by a single superior substance, many effects can be produced by a single superior substance. And it seems quite fitting that the first motion of corporeal things, on which all other motions depend, should have as its cause the principle of immate:ial substances, so that there should be some connection and order between sensible and intelligible things. A problem can arise, however, regarding the Philosopher’s statement that the order of separate substances corresponds to the order of motions and bodies moved. For of all the planets the sun is the largest in size, and its effect is more evident in lower bodies; and even the motions of the other planets are arranged in accordance with the motion of the sun, and in a sense are subsequent to it. Hence it seems that the substance which moves the sun is nobler than the substances which move the other planets, even though the sun is not located above the other planets. But since among bodies one which contains is more formal, and is thereby nobler and more perfect, and is related to a contained body as a whole to a part, as is said in Book IV of the Physics; and since the sphere of a superior planet contains that of an inferior planet, therefore a superior Planet, to which its whole sphere is subordinated, must have a higher and more universal power than an inferior planet, and must produce more lasting effects because it is nearer to the first sphere, which by its motion causes the eternality of things, as has been pointed out above (1065:C 2510). And this is the reason, as Ptolemy says in the Quadripartitum, why the effects of Saturn correspond to universal places and times, and those of Jupiter to years, and those of Mars, the sun, Venus and Mercury to months, and those of the moon to days.
2561. This is also the reason why the effects of the planets appear in lower bodies in accordance with the order among the planets. For the first three highest planets seem to be directed to effects which pertain to the existence of a thing taken in itself; for the very stability of a thing’s act of being is attributed to Saturn, and its perfection and state of well-being to Jupiter, and the power by which it protects itself from what is harmful and drives it away, to Mars. The other three planets seem to have as their proper effects the motion of a being. The sun is a universal principle of motion, and for this reason its operation is most evident in the case of lower motions. For Venus seems to have as its proper effect a more limited one, namely, the process of generation, by which a thing attains its form, and one to which all the other motions among lower bodies are directed. Mercury seems to have as its proper effect the multiplication of things, i.e., the distinction of individuals in the same species; and for this reason it has various motions. It is also mixed with the natures of all the planets, as the astronomers say. The changing of matter and the disposing of it to receive all celestial impressions belongs properly to the moon; and for this reason it seems that it is the planet which transmits celestial impressions and applies them to inferior matter.
2562. Hence the higher a celestial body, the more universal, lasting, and powerful its effect. And since the celestial bodies are the instruments, so to speak, of the separate substances which cause motion, it follows that a substance which moves a higher orb has a more universal knowledge and power, and must therefore be nobler.
2563. But it is now necessary (1081).
Then he investigates the number of these substances; and this is divided into two parts. In the first part (1081:C 2563) he first investigates the number of celestial motions; and in the second (1084:C 2586), he infers from this the number of substances which cause motion (“Hence it is reasonable”).
In regard to the first he does two things. First, he indicates the source from which we must derive the number of celestial motions. Second (1082:C 2567), he gives the different opinions about this (“Now Eudoxus”).
He says, first (1081), that we must use the science of astronomy in studying the number of revolutions or celestial motions, which is a subject that belongs particularly to this branch of the mathematical sciences. For of these sciences only astronomy speculates about sensible and eternal substances, i.e., celestial bodies. But the other mathematical sciences do not consider any substance, as is clear in the case of arithmetic, which treats of numbers, and in the case of geometry, which treats of continuous quantity. Number and continuous quantity are accidents.
2564. That there are many motions belonging to the bodies which move about in the heavens, i.e., the planets, is evident even to those who have little acquaintance with the science of astronomy; for “each of the wandering stars,” i.e., the planets, is moved by several motions and not just by one. Now the planets are called “wandering stars,” not because their motions are irregular, but because they do not always maintain the same pattern and position in relation to the other stars, as these do among themselves and for this reason are called “fixed.”
2565. That there are many motions of stars of this kind is detected in three ways. There is one motion which is perceived by plain sight. There is another which is perceived only by instruments and calculation; and of these motions, some are grasped after a very long period of time, and others after a short one. There is also a third motion, which is demonstrated by reason; for the motion of the wandering stars is found at one time to be more rapid and at another slower; and sometimes a planet seems to be moving forward, and sometimes backward. And because this cannot be in keeping with the nature of a celestial body, whose motion ought to be regular in all respects, it has been necessary to posit different motions by which this irregularity might be reduced to a fitting order.
2566. As to the number of planetary motions, let us now state what the mathematicians say about this, so that with this in mind we may conceive some definite number. But as to the other things which have not been stated, we must either investigate these for ourselves or in this matter accept the opinion of those who do investigate the problem. The same thing applies if some view should appear later on in addition to” those which are now stated by men who treat this kind of problem. And since in choosing or rejecting opinions of this kind a person should not be influenced either by a liking or dislike for the one introducing the opinion, but rather by the certainty of truth, he therefore says that we must respect both parties, namely, those whose opinion we follow, and those whose opinion we reject. For both have diligently sought the truth and have aided us in this matter. Yet we must “be persuaded by the more certain,” i.e., we must follow the opinion of those who have attained the truth with greater certitude.
The Number of Unmoved Movers
ARISTOTLE’S TEXT Chapter 8: 1073b 17-1074b 14
1082. Now Eudoxus claimed that the motion both of the sun and of the moon involves for each three spheres. The first of these is the sphere of the stars whose positions remain unchapged; the second, the one which passes through the middle of the zodiac; and the third, the one which moves obliquely in the latitude of the animals in the zodiac. But the circle in which the moon is moved is inclined at a greater angle than that in which the sun is moved. He also claimed that the motion of the wandering stars involves four spheres for each. The first and second of these are the same as those mentioned above. The sphere of the fixed stars is the one which imparts motion to all of the spheres, and the sphere which is situated below this and moves through the middle of the zodiac is common to all of the planets. The third sphere for each of the planets has its poles in the circle which passes through the middle signs of the zodiac; and the motion of the fourth sphere is in a circle which is inclined at a greater angle to the middle of this sphere; and while the poles of the third sphere are peculiar to each of the other planets, those of Venus and of Mercury are the same.
1083. And Callippus assumed the position of the spheres to be the same as Eudoxus did, i.e., as regards the arrangement of their distances, and he gave the same number of spheres to Jupiter and to Saturn as Eudoxus did. But he thought that two spheres should be added both to the sun and to the moon if appearances are to be saved. And to each of the other planets he added one sphere. However, if all spheres taken together are to account for appearances, there must be additional spheres for each of the other planets, one less in number than those mentioned above, which revolve the planets and always restore to the same place the first sphere of the star which is next in order below. For only in this way can all the spheres account for the motion of the planets. Therefore, since, as regards the spheres in which the planets themselves are carried along, some are eight in number and others twenty-five in number, and of these only those in which the lowest planet is carried along do not need to be revolved, then the spheres which revolve the first two planets will be six in number, and those which revolve the last four will be sixteen in number. The total number of spheres, then, both those which carry the planets along and those which revolve them, will be fifty-five. And if one has not added to the moon and to the sun the motions which we have mentioned (1083), the total number of spheres will be forty-seven. Let the number of the spheres, then, be so many.
1084. Hence it is reasonable to suppose that there are as many substances and immovable principles and perceptible principles. Therefore the statement of necessity is to be left to more powerful thinkers.
1085. However, if there can be no celestial motion which is not related to the motion of a star, and further if every nature and substance which is unchangeable and has in itself reached the highest good must be thought to be an end, there will be no other nature besides these; but this must be the number of substances. For if there were others, they would cause motion as being ends of local motion.
1086. But there cannot be other motions besides those mentioned. And it is reasonable to suppose this from the bodies that are moved. For if everything which moves exists by nature for the sake of that which is moved, and all motion is the motion of something moved, no motion will exist for itself or for the sake of another motion, but all motions will exist for the sake of the stars. For if one motion should exist for the sake of another, the latter must also exist for the sake of another. Hence, since an infinite regress is impossible, the end of every motion must be one of the divine bodies which move about in the heavens.
1087. And it is evident that there is only one heaven. For if there were many heavens, as there are many men, the principle of each would be one in species but many in number. But all things which are many in number have matter; fhr many individuals have one and the same intelligible structure, for example, man, whereas Socrates is one; but the primary quiddity 4 has no matter, for it is complete reality. Therefore the first mover, which is immovable, is one botfi in its intelligible structure and in number; and therefore what is moved eternally and continuously is only one. Hence there is only one heaven.
1088. Now traditions have been handed down from our predecessors and the ancient thinkers, and left to posterity in the form of a myth, that these heavenly bodies are gods, and that the divine encompasses the whole of nature. But the rest of the traditions have been added later in the form of a myth for the persuasion of the multitude, the general welfare, and the passing of laws (172). For they say that the gods have human form and are similar to some of the other animals; and they add other statements which follow upon these and are similar to the ones mentioned. Now if anyone will separate these statements and accept only the first, that they thought the first substances to be gods, this will be considered to he a divine statement. And though every art and every philosophy has often been discovered and again lost, the opinions of these early thinkers have been preserved as relics to the present day. Therefore the opinions of our forefathers and those which have come down to us from the first thinkers are evident only to this extent.
2567. Aristotle states the opinions which the Astronomers of his time held about the number of planetary motions. First (1082:C 2567), he gives the opinion of Eudoxus; and second (1083:C 2578), that of Callippus (“And Callippus”).
Now in regard to the first opinion it must be understood that Plato, in attributing unfailing circularity and order to the celestial motions, made mathematical hypotheses by which the apparent irregular motions of the planets can be explained; for he claimed that the motions of the planets are circular and arranged in an orderly way. And the Pythagoreans, with a view to putting into due order the irregularity which appears in the planetary motions on account of their standing still and moving backwards, and their rapidity and slowness, and their apparent differences in size, claimed that the motions of the planets involve eccentric spheres and small circles which they called epicycles; and Ptolemy 1 also subscribes to this view.
2568. However, something contrary to the points demonstrated in the philosophy of nature seems to follow from this hypothesis; for not every motion will be either towards or away from or around the center of the world. Furthermore it follows that a sphere containing an eccentric sphere either is not of equal density, or there is a vacuum between one sphere and another or there is some body besides the substance of the spheres that lies between them which will not be a circular body and will have no motion of its own.
2569. Further, from the hypothesis of epicycles it follows either that the sphere by which the epicycle is moved is not whole and continuous, or that it is divisible, expansible and compressible in the way in which air is divided, expanded and compressed when a body is moved. It also follows that the body itself of a star is moved by itself and not merely by the motion of an orb; and that from the motion of the celestial bodies there will arise the sound about which the Pythagoreans agreed.
2570. Yet all conclusions of this kind are contrary to the truths established in the philosophy of nature. Therefore Eudoxus, seeing this and seeking to avoid it, claimed that for each planet in the world there are many concentric spheres, each of which has its proper motion and that as a result of all of these motions the observable motion of the planets is accounted for. Hence Eudoxus held that the motion of the sun as well as that of the moon involves three spheres.
2571. For the first motion of the sun as well as that of the moon, which is the daily motion, is that by which they are moved from east to west; and he calls this motion “that of the stars whose positions remain unchanged,” i.e., of the stars which do not wander, namely, the fixed stars; for, as was said above (C 2558), since the motion of the fixed stars, which is from west to east, was not yet discovered to be contrary to the first motion, it was thought that the daily motion was proper to the eighth sphere, which is the sphere of the fixed stars. It was not thought, however, that the first sphere alone might be sufficient to move all the spheres of the planets by a daily motion, as Ptolemy assumed; but he thought that each planet had its own sphere which would move it by a daily motion. Therefore with. a view to explaining this motion he posited a first sphere for both the sun and the moon.
2572. He also posited a second sphere to account for the motion of the sun and the moon. This passes through the middle of the zodiac with what is called “longitudinal motion,” according to which both the sun and the moon are moved from west to east in an opposite direction to the motion of the firmament.
2573. He posited a third sphere to account for the oblique motion across the latitude of the animals symbolized in the zodiac, inasmuch as a planet sometimes seems to be farther south and sometimes farther north of the middle line of the zodiac. But this motion is more apparent and has a broaderspread in the case of the moon than in that of the sun. Hence he adds that the motion by which the moon is carried along is inclined at a greater angle than the sun’s motion. And Ptolemy attributed latitudinal motion to the moon but not to the sun. Hence Eudoxus posited a third motion, as Simplicius says, because he thought that the sun also deviated from the middle line of the zodiac towards the two poles; and he made this assumption because the sun does not always rise in the same place during the summer solstice and during the winter solstice. But if it returned in latitude and in longitude at the same time by means of the declination of the great circle [i.e., the ecliptic] along which the sun travels, one sphere would suffice for this. Since this is not the case, however, but it passes through its course in longitude at one time and returns in latitude at another time, for this reason it was necessary to posit a third sphere. And he claimed that this third sphere of the sun is moved in the same direction as the second sphere, but about a different axis and on different poles. He also claimed that this third sphere of the moon is moved in the same direction as the first sphere. But in each case he claimed that the motion of this third sphere was slower than that of the second.
2574. And he claimed that the motion of each of the other five planets involves four spheres, with the first and second sphere of each planet having the same function as the first and second sphere of the sun and of the moon; because the first motion, which he assumed to be that of the fixed stars, and the second motion, which passes in longitude through the middle line of the zodiac, appear to be common to all the planets.
2575. Next, he posited a third sphere for each of the planets in order to account for their latitudinal motion, and he assumed that the poles about which it is revolved were located in the middle line of the zodiac. But since he claimed that all spheres are concentric, it would follow from this that the zodiac would pass through the poles of the great circle of the third sphere, and it would follow in the opposite way that the great circle of the third sphere would pass through the poles of the zodiac. Hence it would follow that the motion of the third sphere would carry a planet right up to the poles of the zodiac, which is never seen to occur.
2576. Therefore he had to posit a fourth sphere, which is the one that would carry the planet, and it would revolve in an opposite direction to the third sphere, namely, from east to west, in equal time, so as to prevent the planet from being diverted farther in latitude from the zodiac. This is what Aristotle means when he says that Eudoxus claimed that the fourth motion of the star is in a circle inclined at an angle to the middle of the third sphere, i.e., to its great circle.
2577. Therefore, if he posited four spheres for each of the five planets, it follows that there would be twenty spheres for these five planets. And if the three spheres of the sun and the three spheres of the moon a~e added to this number, there will be twentysix spheres in all, granted that the body of each planet is understood to be fastened to the last of its own spheres.
2578. And Callippus assumed (1083).
Then he gives the opinion of Callippus about the number of spheres. Now Callippus, as Simplicius tells us, was associated with Aristotle at Athens when the discoveries of Eudoxus were corrected and supplemented by him. Hence Callippus maintained the same theory of the spheres as Eudoxus did; and he explained the positions of the spheres by the arrangetpent of their distances, because he gave to the planets and to their motions and spheres the same order as Eudoxus did.
2579. And he agreed with Eudoxus as to the number of spheres of Jupiter and Saturn, because he assigned four spheres to each of these; but Callippus thought that two spheres must be added both to the sun and to the moon, if one wants to adopt a theory about them which accords with their motions. He seems to have added these two spheres in order to account for the rapidity and slowness which appears in their motions. The sun would then have five spheres, and the moon likewise would have five. He also added one sphere to each of the remaining planets—Mars, Venus and Mercury—thus giving each of them also five spheres. Perhaps they added this fifth sphere to account for the backward motion and the standing still which appear in these stars. These spheres are called deferent spheres, then, because the body of a planet is carried along by them.
2580. But in addition to these spheres they posited others, which they called revolving spheres. It would appear that they were led to posit these because the last sphere of a higher planet, for example, of Saturn, must share in the motion of all the higher planets, so that its motion gets away somewhat from that of the first sphere. Hence the first sphere of Jupiter, whose poles are fastened in some way to the highest sphere of Saturn, shared to some extent in the motion of the spheres of Saturn, and thus it was not moved uniformly by the daily motion like the first sphere of Saturn. Therefore it seemed necessary to posit another sphere which revolves this first sphere in order to restore the speed which it loses because of the higher planets. And by the same reasoning it was necessary to posit another sphere which revolves the second sphere of Jupiter, and a third sphere which revolves the third sphere of Jupiter. But it was unnecessary to posit another sphere which revolves the fourth sphere, because the motion of the first sphere, to which the star is fixed, must be composed of all the higher motions. Hence Jupiter has four deferent spheres and three revolving spheres. And in a similar way the other planets have as many revolving spheres, minus one, as deferent spheres.
2581. Therefore he says that, if all spheres taken together must account for and explain the apparent motion of the planets, it is necessary to posit, in addition to the deferent spheres mentioned above, other spheres, one less in number, which revolve and restore to the same place the first sphere of the star next in order below; for only in this way can the motions of the planets accord with all appearances.
2582. Therefore, since the deferent spheres which belong to Saturn and to Jupiter are eight in number, because each is assumed to have four spheres; and since those which belong to the other five planets are twenty-five in number, because each of these has five spheres, and of these only those at the end which carry and regulate the star are not revolved, it follows that the revolving spheres of the first two planets, i.e., of Saturn and Jupiter, are six in number, and that those of the last four planets are sixteen in number. But since after Saturn and Jupiter there are five other planets, he evidently tmits one of them, i.e., either Mars or Mercury, so that his statement regarding the last four refers to the four lowest; or he omits the moon, so that he refers to the four planets immediately following. Now he omits this either by error, which sometimes happens in the case of numbers, or for some reason which is unknown to us; because the writings of Callippus are not extant, as Simplicius tells us. Hence the total number of deferent spheres and of revolving spheres together is fifty-five.
2583. But because the difficulty could arise whether it is necessary to add two spheres to the sun and two to the moon, as Callippus did, or whether only two spheres must be given to each, as Eudoxus claimed, he therefore says that, if one does not add two motions to the sun and two to the moon, as Callippus did, it follows that the total number of spheres will be forty-seven; for four deferent spheres would then be subtracted from the above numbertwo for the stin and two for the moon —and also the same number of revolving spheres; and when eight is subtracted from fifty-five, forty-seven remains.
2584. But it must be noted that, if above (1083:C 2582), when he said that the revolving spheres of the last four planets are sixteen in number, he omitted the moon, then if two deferent spheres are subtracted from the moon and two from the sun, four revolving spheres are not subtracted but only two, granted that the spheres of the moon do not have revolving spheres; and thus six spheres are subtracted from the first number of spheres, i.e., four deferent and two revolving spheres; and then it follows that the total number of spheres is forty-nine. Hence it seems that Aristotle did not wish to omit the moon but rather Mars, unless one says that Aristotle had forgotten that he had assigned revolving spheres to the moon, and that this is the reason the mistake was made, which does not seem likely.
2585. Last, he draws his conclusion that the number of spheres is that mentioned.
2586. Hence it is reasonable (1084).
Then he infers the number of immaterial substances from the number of celestial motions; and in regard to this he does three things. First (1084:C 2586), he draws the conclusion at which he aims. Second (1085:C 2587), he rejects certain suppositions which could weaken the foregoing inference (“However, if there can be”). Third (1088:C 2597), he compares the points demonstrated about separate substance with the opinions of the ancients and with the common opinions held about these things during his own time (“Now traditions have”).
He says, first (1084), that, since the number of celestial spheres and the number of celestial motions is as has been stated, it is reasonable to suppose that there are the same number of immaterial substances and immobile principles, and even the same number of “perceptible principles,” i.e., celestial bodies. He uses the term reasonable in order to imply that this conclusion is a probable one and not one that is necessary. Hence he adds that he is leaving the necessity of this to those who are stronger and more capable of discovering it than he is.
2587. However, if there can be (1085).
Here the Philosopher rejects those suppositions by which the conclusion given above could be weakened; and there are three of ihese. The first is that one could say that there are certain separate substances to which no celestial motion corresponds.
2588. In order to reject this he says that, if there can be no celestial motions which are not connected with the motion of some star, and again if every immutable substance which has reached “in itself the highest good,” i.e., which has reached its own perfection without motion, must be considered an end of some motion, there wilt be no immutable and immaterial nature besides those substances which are the ends of celestial motions; but the number of separate substances will correspond necessarily to the number of celestial motions.
2589. Yet the first assumption is not necessary, namely, that every immaterial and immutable substance is the end of some celestial motion. For it can be said that there are separate substances too high to be proportioned to the celestial motions as their ends. And this is not an absurd supposition. For immaterial substances do not exist for the sake of corporeal things, but rather the other way around.
2590. But there cannot be (1086).
Then he rejects the second supposition which could weaken the inference mentioned above. For one could say that there are many more motions in the heavens than have been counted, but that these cannot be perceived because they produce no diversity in the motion of one of the celestial bodies which are perceived by the sense of sight and are called stars.
2591. And in order to reject this he had already equivalently said that there can be no celestial motion which is not connected with the motion of some star. His words here are that there cannot be other motions in the heavens besides those which produce the diversity in the motions of the stars, whether they be the motions mentioned or others, either the same in number or more or fewer.
2592. This can be taken as a probable conclusion from the bodies which are moved; for if every mover exists for the sake of something moved, and every motion belongs to something which is moved, there can be no motion which exists for itself or merely for the sake of another motion, but all motions must exist for the sake of the stars. For otherwise, if one motion exists for the sake of another, then for the same reason this motion also must exist for the sake of another. Now since an infinite regress is impossible, it follows that the end of every motion is one of the celestial bodies which are moved, as the stars. Hence there cannot be any celestial motion as a result of which some diversity in a star cannot be perceived.
2593. And it is evident (1087).
Then he rejects a third supposition by which the above inference could be weakened. For someone might say that there are many worlds, and that in each of these there are as many spheres and motions as there are in this world, or even more, and thus it is necessary to posit many immaterial substances.
2594. He rejects this position by saying that there is evidently only one heaven. If there were many numerically and the same specifically, as there are many men, a similar judgment would also have to be made about the first principle of each heaven, which is an immovable mover, as has been stated (1079:C 2555). For there would have to be many first principles which are specifically one and numerically many.
2595. But this view is impossible, because all things which are specifically one and numerically many contain matter. For they are not differentiated from the viewpoint of their intelligible structure or form, because all the individuals have a common intelligible structure, for example, man. It follows, then, that they are distinguished by their matter. Thus Socrates is one not only in his intelligible structure, as man, but also in number.
2596. However, the first principle, “since it is a quiddity,” i.e., since it is its own essence and intelligible structure, does not contain matter, because its substance is “complete reality,” i.e., actuality, whereas matter is in potentiality. It remains, then, that the first unmoved mover is one not only in its intelligible structure but also in number. Hence the first eternal motion, which is caused by it, must be unique. It therefore follows that there is only one heaven.
2597. Now traditions (1088).
He shows how the points discovered about an immaterial substance compare with both the ancient and common opinions. He says that certain traditions about the separate substances have been handed down from the ancient philosophers, and these have been bequeathed to posterity in the form of a myth, to the effect that these substances are gods, and that the divine encompasses the whole of nature. This follows from the above points, granted that all immaterial substances are called gods. But if only the first principle is called God, there is only one God, as is clear from what has been said. The rest of the tradition has been introduced in the form of a myth in order to persuade the multitude, who cannot grasp intelligible things, and inasmuch as it was expedient for the passing of laws and for the benefit of society, that by inventions of this kind the multitude might be persuaded to aim at virtuous acts and avoid evil ones. He explains the mythological part of this tradition by adding that they said that the gods have the form of men and of certain other animals. For they concocted the fables that certain men as well as other animals have been turned into gods; and they added certain statements consequent upon these and similar to the ones which have just been mentioned. Now if among these traditions someone wishes to accept only the one which was first noted above, namely, that the gods are immaterial substances, this will be considered a divine statement, and one that is probably true. And it is so because every art and every philosophy has often been discovered by human power and again lost, either because of wars, which prevent study, or because of floods or other catastrophes of this kind.
2598. It was also necessary for Aristotle to maintain this view in order to save the eternity of the world. For it was evident that at one time men began to philosophize and to discover the arts; and it would seem absurd that the human race should be without these for an infinite period of time. Hence he says that philosophy and the various arts were often discovered and lost, and that the opinions of those ancient thinkers are preserved as relics up to the present day.
2599. Last, he concludes that “the opinion of our forefathers,” i.e., the one received from those who philosophized and after whom philosophy was lost, is evident to us only in this way, i.e., in the form of a myth, as has been stated above (1088:C 2597).
The Dignity of the First Intelligence
ARISTOTLE’S TEXT Chapter 9: 1074b 15-1075a 10
1089. The things which pertain to intellect (or mind) involve certain difficulties; for of the things apparent to us it seems to be the most divine; but how it is so gives rise to certain difficulties.
1090. For if it is not actually understanding, but is in a sense like one asleep, what dignity will it have? Or if it is understanding, but its chief good is different from itself, then, since its essence is not an act of understanding but a potentiality, it will not be the best substance; for it is by reason of its act of understanding that dignity belongs to it.
1091. Furthermore, whether its substance is its power to understand or its act of understanding, what does it understand? For it understands either itself or something else; and if something else, either the same thing always or something different.
1092. Does it make any difference or not, then, whether it understands what is good or what is contingent? Or is it absurd that it should ponder about certain things?
1093. Hence it is evident that it understands what is most divine and honorable, and that it does not change; for a change would be for the worse, and this would already be motion.
1094. Therefore, if the first mover is not its act of understanding but a potency, it is reasonable to assume, first, that the continuity of its act of understanding is laborious to it (797).
1095, Second, that there is evidently something else more honorable than intellect, namely, what it understands. For both the power to understand and understanding itself belong even to one who understands the basest thing. This must accordingly be avoided; for there are some things which it is better not to see than to see. But this will not be so if the act of understanding is the best of things. Therefore, if there is a most powerful intellect, it must understand itself.
1096. And its act of understanding is an understanding of understanding. But science, perception, opinion and thought always seem to be about something else and only indirectly about themselves.
1097. Again, if understanding is something different from being understood, from which of these does the intellect derive its goodness? For the essence of understanding and that of being understood are not the same.
1098. But in certain cases is not understanding identical with the thing understood? For in the productive sciences the object is the substance or quiddity without matter; and in the theoretical sciences the intelligible structure is both the object and the understanding of it. Therefore, since the object of understanding does not differ from the act of understanding in the case of things which have no matter, they will be the same; and the act of understanding will be identical with the thing understood.
1099. Yet the difficulty still remains whether the thing that it understands is composite; for if it is, the intellect will be changed in passing from one part of the whole to another.
1100. Now whatever does not have matter is indivisible, for example, the human mind.
1101. And the act of understanding composite things involves time. For it does not possess its goodness at this or at that moment but attains the greatest good over a whole period of time, and this is something different from itself. And an intellect which understands itself is in this state through all eternity.
2600. Having settled the issue about the perfection and oneness of this immaterial substance, the Philosopher now meets certain difficulties concerning its activity; for it has been shown above (1067-70:C 2519-35) that the first immaterial substance causes motion as an intelligible object and a desirable good. This is divided into two parts. In the first (1089:C 2600) he settles certain difficulties about the first immaterial substance insofar as it is an intelligible good and an intellect; and in the second (1102:C 2627), insofar as it is a desirable good (“We must also inquire”).
In regard to the first he does two things. First, he gives the reason for the difficulty concerning the intellect of the first substance. Second (1090:C 2901), he raises and meets this difficulty (“For if it is not”).
He accordingly says, first (1089), that, the things which pertain to the intellect of the first immaterial substance involve certain difficulties, and these seem to arise as follows. The Philosopher has shown that the intellect which understands and desires the first inovrr, which causes inotion
as an object of understanding and of desire, has something nobler than itself, namely, what is understood and desired by it. He has also shown that the first intelligible object itself is also an intellect. Hence for a like reason it could appear that the first intellect also has something nobler and higher than itself, and that it therefore is not the highest and best thing. But this is contrary to the truths which are apparent about the first principle; and so he says here that it seems evident to all that this principle is the noblest. Yet certain difficulties emerge if one wishes to explain how it is “noblest,” i.e., best and most perfect.
2601. For if it is not (1090).
Then he clears up these difficulties; and in regard to this he does three things. First, he raises the difficulties. Second (1093:C 2606), he prefaces his discussion with certain prerequisites for meeting all the questions raised (“Hence it is evident”). Third (1094:C 2608), he solves these difficulties (“Therefore, if the first mover”).
In regard to the first he does two things. First (1090), he raises the qucstions in which he is chiefly interested. Second (1092:C 2604), he introduces an additional question whose solution is necessary for solving the questions raised (“Does it make”).
First of all he raises two questions. He asks, first, how the intellect of the first mover is related to its own act of understanding; and second (1091:C 2603), how it is related to its own intelligible object (“Furthermore, whether”).
Now it should be noted that an intellect can be related to its own act of understanding in three ways: first, actual understanding does not,belong to it but only potential or habitual understanding; second, actual understanding does belong to it; and third, it is identical with its own act of understanding or its own knowledge, which are the same thing.
2602. He accordingly says, first (1090), that, if the intellect of the first mover is not actually understanding but only potentially or habitually understanding, it will have no dignity; for the goodness and nobility of an intellect consists in its actually understanding, and an intellect that is only potentially or habitually understanding is like one asleep. For one asleep has certain powers which enable him to perform vital optrations even though he is not using them, and thus he is said to be half alive; and during sleep there is no difference between happiness and unhappiness or between virtue and vice. But if the intellect of the first intelligence is actually understanding, yet its chief good, which is its activity, is something different from itself because its “act of understanding,” i.e., its intellectual activity, is not identical with its own essence, then its essence is related to its act of understanding as potentiality to actuality, and as something perfectible to its perfection. It accordingly follows that the first intellect is not the best substance; for it is by reason of its act of understamling that lionor and nobility belong to it, and nothing that is noble in comparison with something else is noblest in itself. It seems to follow, then, that the essence of the first intellect is not the best, whether it understands only potentially or actually, unless one assumes along with this that its very essence is identical with its act of understanding, as he will establish later on (1094:C 2608).
2603. Furthermore, whether its substance (1091).
Before he answers the questions raised he asks another about the intelligible object of the first mover. He says that, whether the essence of the first mover is its power to understand or its “act of understanding,” i.e., its intellectual activity or thought (this was the first question raised), we must still ask what it understands? For it understands either itself or something else. And if it understands something else, it must understand either the same thing always or something different, i.e., sometimes one thing and sometimes another.
2604. Does it make any difference (1092).
So before he answers the foregoing questions, he introduces another question whose solution is useful in giving the answer; that is, whether it makes any difference or none at all to the nobility or perfection of the intellect that it should understand what is good and noble or what is contingent.
26o5. By using an instance he shows that it does make a difference, because it seems incongruous and unreasonable that anyone should ponder or employ the operation of his intellect on things that are base. That this should not be the case would demand that the nobility of the intellect be independent of the nobility of its object, and that the understanding of base things be no different from the understanding of good things. But this is quite impossible, since activities are evidently specified by their proper objects. Hence the nobler an object, the nobler must be the operation.
2606. Hence it is evident (1093).
He prefaces his discussion with certain points necessary for answering the main questions. First, he gives two points. He infers the first of these from the solution of the question which he interjected. For, if it does make a difference to the nobility of the intellect whether it understands what is good or what is contingent, as has been stated (1092:C 2605), then, since the first intellect is the noblest, it obviously knows what is most divine and most honorable.
2607. The second point is the solution given to the last part of the second main question. The question was whether the intellect of the first mover changes from one intelligible object to another. Now it is evident that it does not change from one object to another. For, since it understands what is most divine, if it were to change from one object to another, it would change to a less noble one; but this is fitting only to something tending to defect and destruction. Moreover, this change from one intelligible object to another would be a kind of motion; and therefore it could not be fitting to the first mover, since he is immovable in every respect.
2608. Therefore, if the first mover (1094).
He nows answers the questions first raised. First, he gives the correct solution to the first question; and second (1095:C 2611), the solution to the second question (“Second, that”).
He answers the first question as follows. If the substance of the first mover “is not its act of understanding,” i.e., its own intellectual activity, but an intellective potency, “it is reasonable,” i.e., it seems to follow as a probable conclusion, that “the continuity of its act of understanding,” i.e., of its intellectual operation, is laborious to it. For whatever is in potentiality to something else is related hoth to this something else and to its opposite, because what can be can also not be. Hence, if the substance of the first mover is related to its act of understanding as potentiality to actuality, then according to the nature of its own substance it will be able both to understand and not to understand. Therefore continuous understanding will not be proper to it by reason of its own substance.
2609. In order not to be sometimes like one asleep it must derive the continuity of its intellectual activity from something else. Now whatever a thing acquires from something else and does not have by its own nature is probably laborious to it, because this is true in our case; for when we act continuously we labor. But this conclusion is not necessary, because that which one thing acquires from something else is laborious to it only if the thing acquired or something connected with it is contrary to its nature. Therefore, even though the continuity of the motion of the heavens depends on some external principle, such motion is not laborious.
2610. Hence Aristotle was content here to reduce to absurdity the probable conclusion which follows, because the untenable conclusion which necessarily follows is evident, namely, that the goodness and perfection of the first mover will depend on some higher entity; for then it would not be the first and best.
2611. Second, that there is (1095).
He now answers the second question; and in regard to this he does three things. First, he establishes the correct answer to the second question. Second (1096:C 2617), he argues on the opposite side of the question (“And its act of understanding”). Third (1098:C 2619), he answers the arguments given (“But in certain cases”).
He accordingly says, first (1095), that, since it has been shown (1094:C 2608) that the substance of the first mover is not an intellective potency but is itself an act of understanding, it is evident from this that, if the first mover does not understand itself but something else, it follows that this other thing, i.e., what is understood by it, is nobler than the first mover.
2612. He proves this as follows. Actual understanding itself, i.e., thinking, also belongs to one who understands the basest thing. Hence it is evident that some actual understanding must be avoided, because there are some things which it is better not to see than to see. But this would not be the case if the act of understanding were the best of things, because then no act of understanding would have ic, be avoided. Therefore, since some act of understanding must be avoided because of the baseness of the thing understood, it follows that the nobility of the intellect, which is found in its understanding, will depend on the nobility of its object. Hence the intelligible object is nobler than the act of understanding.
2613. Since it has been shown that the first mover is its own act of understanding, it follows that if it understands something different from itself, this other thing will be nobler than it is. Therefore, since the first mover is the noblest and most powerful, it must understand itself; and in its case intellect and thing understood must be the same.
2614. Now we must bear in mind that the Philosopher’s aim is to show that God does not understand something else but only himself, inasmuch as the thing understood is the perfection of the one understanding and of his activity, which is understanding. It is also evident that nothing else can be understood by God in such a way that it would be the perfection of His intellect. It does not follow, however, that all things different from Himself are not known by Him; for by understanding Himself He knows all other things.
2615. This is made clear as follows. Since God is His own act of understanding and is the noblest and most powerful being, His act of understanding must be most perfect. Therefore He understands Himself most perfectly. Now the more perfectly a principle is known, the more perfectly is its effect known in it; for things derived from principles are contained in the power of their principle. Therefore, since the heavens and the whole of nature del pend on the first principle, which is God, God obviously knows all things by understanding Himself.
2616. And the baseness of any object of knowledge does not lessen His dignity; for the actual understanding of anything more base is to be avoided only insofar as the intellect becomes absorbed in it, and when in actually understanding that thing the intellect is drawn away from the understanding of nobler things. For if in understanding some noblest object base things are also understood, the baseness of the things understood does not lessen the nobility of the act of understanding.
2617. And its act of understanding (1096).
Then he raises two objections against the correct solution. The first is as follows. The first mover understands himself, as has been shown above (1095:C 2615); and he is his own act of understanding, as has also been shown (1094:C 2608). Hence his act of understanding does not differ f rom his act of understanding his own thought. But this is contrary to what seems to be true, because perception, science, opinion and thought always seem to be about something else. And if they are sometimes about themselves, as when someone perceives that he perceives, or knows that he knows, or is of the opinion that he has an opinion, or thinks that he is thinking, this seems to be something in addition to the principal act or operation; for the principal act here seems to be that whereby someone understands an intelligible object. But that someone should understand that he is understanding something intelligible seems to be accessory to the principal act. Thus if the first mover’s act of understanding consists solely in his understanding his own thought, it seems to follow that his act of understanding is not the most important thing.
2618. Again, if understanding (1097).
Then he raises a second objection against the correct solution. He says that the act of understanding and the thing understood are obviously different; and even if it were possible for an intellect and its object to be the same in reality, they would not be the same in their formal structure. Hence, if the first mover is himself both his act of understanding and the object that is being understood, which is the best of things, there still seems to be the problem as to which of these confers goodness on him, namely, his act of understanding or the thing understood.
2619. But in certain cases (1098).
He now answers the objections raised. He says that in certain cases the thing understood is the same as the knowledge of it. This becomes clear when we draw a distinction between the sciences; for one kind of science is productive and another is speculative. In the case of a productive science the thing understood, taken without matter, is the science of that thing; for example, it is clear that a house without matter, insofar as it exists in the mind of the builder, is the very art of building; and similarly health in the mind of the physician is the medical art itself. Thus a productive art is evidently nothing else than the substance or quid, dity of the thing made; for every artist proceeds to his work from a knowledge of the quiddity which he intends to produce.
2620. In the case of the speculative sciences it is evident that the concept, which defines the thing itself, is the thing understood and the science or knowledge of that thing. For an intellect has knowledge by reason of the fact that it possesses the concept of a thing. Therefore, since in the case of all those things which do not have matter the intellect when actually understanding does not differ from the thing understood, then in the case of the first substance, which is separate from matter in the highest degree, the act of understanding and the thing understood are evidently the same in the highest degree. Hence there is just one act of understanding pertaining to the thing understood; that is, the act of understanding the thing understood is not distinct from that of understanding the act of understanding.
2621. Yet the difficulty (1099).
Here he raises a third question in addition to the two dealt with above. For since it has been shown (1074:C 2544) that the first mover understands himself, and a thing is understood in two ways: first, by way of a simple understanding, as we understand a quiddity, and second, by way of a composite understanding, as we know a proposition, the question therefore arises whether the first mover understands himself by way of a simple understanding, or by way of a composite one. This is what he refers to when he says that the difficulty still remains whether the object of God’s understanding is composite.
2622. Now he shows that it is not composite when he says (1099) “for if it is”; and he gives three arguments in support of this. The first goes as follows. In every composite object of understanding there are several parts, which can be understood separately. For even though this composite object of understanding Man runs, insofar as it is one composite object, is understood all at once, none the less its parts can be understood separately. For the term man can be understood by itself, and so also can the term runs. Hence, whoever understands some composite object can be changed when his act of understanding passes from one part to another. Therefore, if the first intelligible object is composite, it follows that the intellect can change when its act of understanding passes from one part of this object to another. But the contrary of this has been proved above (1098:C 2619).
2623. Now whatever (1100).
Then he gives the second argument. Whatever does not have matter is Simple and indivisible. But the first intellect does not have matter. Therefore it is simple and indivisible.
2624. He gives as an example the human intellect, and this example can be taken in two ways. First, it can be taken as a comparison, meaning that the human intellect is indivisible in its own essence, because it is an immaterial form in every respect.
2625. It can also be taken in a second and better way as a contrast, meaning that the human intellect knows composite things because it derives its intelligible objects from material things. And this is not true of the first intellect.
2626. And the act (1101).
He gives the third argument. An act of understanding which is concerned with composite things does not possess its perfection always but attains it over a period of time. This is clear from the fact that it does not attain its good in knowing one part or another, but its greatest good is something else, which is a kind of whole. Hence the truth (which is the good of the intellect), is not found in simple things but in a composite one. Further, simple things are prior to composite things as regards both generation and time, so that whatever does not possess its own good in knowing parts which can be understood separately but in knowing the whole which is constituted of them, attains its good at some particular moment and does not always possess it.—However, the first mover’s act of understanding, which is of himself, is eternal and always in the same state. Therefore the thing understood by the intellect of the first mover is not composite.
God Is the Final Cause of All Things. The Order of the Universe
ARISTOTLE’S TEXT Chapter 10: 1075a 11-1076a 4
1102. We must also inquire how the nature of the whole [universe] contains the good and the highest good, whether as something separate and self-subsisting or as the order of its parts.
1103. Or is it in both ways, as an army does? For the good of an army consists both in its order and in its commander, but mainly in the latter; for he does not exist for the sake of the order, but the order exists for him.
1104. And all things, both plants and animals (those that swim and those that fly), are ordered together in some way, but not alike; and things are not such that there is no relation between one thing and another, but there is a connection. For all things are ordered together to one end, but in the same way as in a household, where the children are not permitted to do just as they please, but all or most of the things done are arranged in an orderly way, while the slaves and livestock do little for the common good but act for the most part at random. For the nature of each of these constitutes such a principle. I mean that by it all must be able to be distinguished. And there are other activities which all have in common for the sake of the whole.
1105. And we must not fail to consider all the impossible and incongruous conclusions that confront those who explain things differently, and what sort of views are expressed by the more popular thinkers, among whom the fewest difficulties appear.
1106. For all these thinkers derive all things from contraries. But neither “all things” (1055) nor “from contraries” (1029) is correct; nor do they explain how the things in which contraries are present come from contraries.
1107. For contraries cannot be acted upon by one another. But this difficulty is solved by us in a reasonable way on the ground that there is a third element. Some thinkers make one of the contraries matter, as those who make the unequal the matter of the equal, or the many the matter of the one. But this is also met in the same way; for matter, as one, is contrary to nothing.
1108. Further, [according to them] all things except the one will exist by participating in evil; for evil itself is one of the two elements (78).
1109. For other thinkers consider neither good nor evil as principles, even though the good is in the fullest sense a principle of things.
1110. The former are right in holding that the good is a principle, but they do not say how it is a principle: whether as an end or as a mover or as a form.
1111. And Empedocles’ doctrine (50) is also unreasonable; for he identifies the good with friendship, although the latter is a principle both as a mover (for it combines things), and as matter (for it is a part of the mixture 4). Therefore, even if it happens that the same thing is a principle both as matter and as a mover, still their being is not the same. In what respect, then, is friendship a principle? And it is also unreasonable that strife should be indestructible; for the essence of evil, for him, is precisely this strife.
1112. Again, Anaxagoras makes the good a principle as a mover; for his “Intellect” causes motion. But it causes motion for the sake of some goal, and therefore there must be something other than intellect (84), unless it is as we say; for the art of medicine is in a sense health (6o6). It is also unreasonable not to provide something that is contrary to the good (78) or to intellect.
1113. But all who speak of contraries fail to make use of them as such, except that some make use of imagery. And none of them explain why some things are destructible and others are not; for they derive all things from the same principles (250-263). Again, some derive beings from non-being, while others (63) lest they be driven to this, make all things one.
1114. Further, no one explains why there is always generation, and what its cause is.
1115. And those who posit two principles of things must assume a first principle which is superior. This also holds for those who posit separate Forms, because there is another principle which is more important; for why has matter participated in the Forms or why does it participate in them?
1116. And for other thinkers there must be something contrary to wisdom or the noblest science; but this is not so in our case. For there is nothing contrary to what is primary, since all contraries involve matter, and things having matter are in potentiality; and ignorance is contrary to the particular knowledge which is the contrary into which it can pass. But there is nothing contrary to what is primary.
1117. Further, if nothing exists except sensible things, there will be no principle, no order, no generation, no heavenly bodies; but every principle will have a principle, as is maintained by all the theologians and natural philosophers.
1118. Now if there are separate Forms and numbers, they will not be causes of anything; but if they are, they will certainly not be causes of motion.
1119. Again, h6w will extension or continuous quantity be composed of parts which are unextended? For number cannot either as a mover or as a form produce a continuum.
1120. Further, no one of the contraries will be a productive principle and a mover, because it would be possible for it not to be. And in any case its activity would be subsequent to its potentiality. No beings, then, would be eternal. But some are. Therefore one of these premises must be rejected. How this may be done has been explained (1057).
1121. Again, as to the way in which numbers, or soul and body, or forms and things in general are one, no one states anything; nor is it possible to do so unless he says, as we do, that a mover makes them one (733-41).
1122. And those who say that mathematical number is the primary reality and that there is always one substance after another and give different principles for each, make the substance of the universe itself a group of substances unrelated to each other (for one substance confers nothing upon another, either by being or not being), and give us many principles. But beings do not want to be badly disposed.—“Many rulers are not good; therefore let there be one ruler.”
2627. Having shown how the first mover is both an intelligence and an intelligible object, here the Philosopher aims to investigate how the first mover is a good and an object of desire; and in regard to this he does two things. First (1102:C 2628), he shows how the good is present in the universe, according to his opinion; and second (1105:C 2638), according to the opinions of other philosophers (“And we must not fail”).
In regard to the first he does two things. First, he raises a question. Second (1103:C 2629), he answers it (“Or is it”).
Now this question arises because of a statement which was made above to the effect that the first mover causes motion as something good and desirable; for good, inasmuch as it is the end or goal of a thing, is twofold. For an end is extrinsic to the thing ordained to it, as when we say that a place is the end of something that is moved locally. Or it is intrinsic, as a form is the end of the process of generation or alteration; and a form already acquired is a kind of intrinsic good of the thing whose form it is. Now the form of any whole which is one through the arrangement of its parts is the order of that whole. Hence it follows that it is a good of that whole.
2628. Therefore the Philosopher asks whether the nature of the whole universe has its good and highest good, i.e., its proper end, as something separate from itself, or whether this consists in the ordering of its parts in the way in which the good of any natural being in its own form.
2629. Or is it (1103).
Then he answers the question raised; and in regard to this he does two things. First, he shows that the universe has both a separate good and a good of order. Second (1104:C 2632), he shows the ways in which the parts of the universe contribute to its order (“And all things”).
He accordingly says, first (1103), that the universe has its good and end in both ways. For there is a separate good, which is the first mover, on which the heavens and the whole of nature depend as their end or desirable good, as has been shown (1067:C 2520. And since all thiiigs having one end must agree in their ordination to that end, some order must be found in the parts of the universe; and so the universe has both a separate good and a good of order.
2630. We see this, for example, in the case of an army; for the good of the army is found both in the order itself of the army and in the commander who has charge of the army. But the good of the army is found in a higher degree in its commander than in its order, because the goodness of an end takes precedence over that of the things which exist for the sake of the end. Now the order of an army exists for the purpose of achieving the good of its commander, namely, his will to attain victory. But the opposite of this is not true, i.e., that the good of the commander exists for the sake of the good of order.
2631. And since the formal character of things Which exist for the sake of an end is derived from the end, it is therefore necessary not only that the good of the army exist for the sake of the commander, but also that the order of the army depend on the commander, since its order exists for the sake of the commander. In this way too the separate good of the universe, which is the first mover, is a greater good than the good of order which is found in the universe. For the whole order of the universe exists for the sake of the first mover inasmuch as the things contained in the mind and will of the first mover are realized in the ordered universe. Hence the whole order of the ~niverse must depend on the first mover.
2632. And all things (1104).
Here he shows the ways in which the parts of the universe contribute to its order. He says that all things in the universe are ordered together in some way, but not all are ordered alike, for example, sea animals, birds, and plants. Yet even though they are not ordered in the same way, they are still not disposed in such a way that one of them has no connection with another; but there is some affinity and relationship of one with another. For plants exist for the sake of animals, and animals for the sake of men. That all things are related. to each other is evident from the fact that all are connected together to one end.
2633. That all are not ordered in the same way is made clear by an example; for in an ordered household or family different ranks of members are found. For example, under the head of the family there is a first rank, namely, that of the sons, and a second rank, which is that of the slaves, and a third rank, which is that of the domestic animals, as dogs and the like. For ranks of this kind have a different relation to the order of the household, which is imposed by the head of the family, who governs the household. For it is not proper for the sons to act in a haphazard and disorderly way, but all or most of the things that they do are ordered. This is not the case with the slaves or domestic animals, however, because they share to a very small degree in the order which exists for the common good. But in their case we find many things which are contingent and haphazard; and this is because they have little connection with the ruler of the household, who aims at the common good of the household.
2634. And just as the order of the family is imposed by the law and precept of the head of the family, who is the principle of each of the things which are ordered in the household, with a view to carrying out the activities which pertain to the order of the household, in a similar fashion the nature of physical things is the principle by which each of them carries out the activity proper to it in the order of the universe. For just as any member of the household is disposed to act through the precept of the head of the family, in a similar fashion any natural being is disposed by its own nature. Now the nature of each thing is a kind of inclination implanted in it by the first mover, who directs it to its proper end; and from this it is clear that natural beings act for the sake of an end even though they do not know that end, because they acquire their inclination to their end from the first intelligence.
2635. However, not all things are disposed to this end in the same way. For there is something common to all things, since all things must succeed in being distinguished; that is, they must have discrete and proper operations, and must also be differentiated essentially from each other; and in this respect order is lacking in none of them. But there are some things which not only have this but are also such that all their activities “participate in the whole,” i.e., are directed to the common good of the whole. This is found to be true of those things which contain nothing contrary to their nature, nor any element of chance, but everything proceeds according to the right order.
2636. For it is evident, as has been pointed out (1104:C 2632-34), that each natural being is directed to the common good by reason of its proper natural activity. Hence those things which never fail in their proper natural activity have all their activities contributing to the whole. But those which sometimes fail in their proper natural activity do not have all their activities contributing to the whole; and lower bodies are of this kind.
2637. The answer briefly stated, then, is that order requires two things: a distinction between the things ordered, and the contribution of the distinct things to the whole. As regard the first of these, order is found in all things without fail; but as regards the second, order is found in some things, and these are the things which are highest and closest to the first principle, as the separate substances and the heavenly bodies, in which there is no element of chance or anything contrary to their nature. But order is lacking in some things, namely, in [lower] bodies, which are sometimes subject to chance and to things which are contrary to their nature. This is so because of their distance from the first principle, which is always the same.
2638. And we must not (1105).
Then he deals with the end and order of the universe according to the opinion of other philosophers. In regard to this he does two things. First, he explains what he aims to do. He says that we must state all the impossible or incongruous conclusions facing those who express views different from our own about the good and order of the universe; and we must also state the kind of views held by those men who give a better explanation of things and in whose statements fewer difficulties appear.
2639. For all these (1106).
He then carries out his plan. In regard to this he does two things. First (1106:C 2639), he gives the opinion of those who held that the principles of things are contraries; and second (1117:C 2656), the opinion of those who held that the principles of things are separate natures (“Further, if nothing”).
In treating the first point he does two things. First (1106), he explains in what way those men are wrong who say that the principles of things are contraries. He says that all the ancient philosophers held that all things come from contraries as their principles; and they were wrong on three counts. First, they were wrong in holding that things come from contraries; and second, in saying that all things come from contraries; and third, in failing to explain how things are produced from contraries.
2640. For contraries (1107).
Second, he indicates how they were wrong in the three ways mentioned above. He explains how they erred, first, in holding that things come from contraries; and second (1108:C 2643), in claiming that all things come from contraries (“Further, [according to them]”); and third (1113:C 2650), in failing to show how things come from contraries (“But all who speak”).
He accordingly says, first (1107), that they were wrong in saying that things comes from contraries, because contraries taken in themselves cannot be acted upon by one another; for whiteness is not acted upon by blackness or vice versa, and one thing could come from them only if they were influenced by one another and so were reduced to an intermediate state.
2641. But in Aristotle’s opinion this difficulty is easily solved, because besides the two contraries he also posited a third principle, matter. Hence one of the two contraries can be acted upon by the other in the sense that matter, which is the subject of one contrary, can be acted upon by the other contrary.
2642. But others claimed that matter is one of the two contraries and not something distinct from them, as is evident in the case of those who held that the contraries, the unequal and the equal, and the one and the many, are principles. For they attribute inequality and plurality to matter, and equality and unity to form, as is found in Plato’s opinion, although the natural philosophers held the opposite. But this statement of theirs is met in the same way, because matter, which is one thing as the common subject of contraries, is contrary to nothing.
2643. Further, [according to them] (1108).
Then the Philosopher explains how these thinkers were wrong in saying that all things come from contraries; and in regard to this he does two things. First, he shows the unreasonable conclusion which follows from this view. For it is evident that the primary contraries are good and evil, because one of two contraries is always the privation of the other and so has the character of evil. Therefore, if all things come from contraries, it follows that all things participate in evil as well as in unity, i.e., good, which is a principle; for good is posited as one of the two elements, and everything else is supposed to come from these two principles. But this is not true, because destruction and evil are not found in the heavenly bodies or in the nature of the separate substances.
2644. For other thinkers (1109).
Second, he shows that the position of all those who held that all things come from contraries is not in agreement with the position of certain of the philosophers. For if all things come from contraries, it follows, as has been pointed out, that good and evil are the first principles of things. But some did not claim that good and evil are principles but said that the good is the principle of all things.
2645. The former (1110).
Third he indicates the error made even by those who claimed that the good is a principle of things. He makes this clear, first, in a general way. He says that, even though some philosophers are right in holding that the good is a principle of all things, they are still wrong in failing to show how it is a principle, i.e., whether as an end or as a form or as a mover. For these things are characterized by perfection and goodness, whereas matter which is perfected only by form, does not have the character of something good and perfect; and therefore he makes no mention of it.
2646. And Empedocles’ doctrine (1111).
Next, he turns to certain particular opinions. First, he considers the opinion of Empedocles. He says that Empedocles made the unreasonable assumption that the good is a principle of things; for he claimed that love is a principle, identifying it with the good. However, he said that love is a principle in two ways. For he claimed that it is a moving principle inasmuch as its function is to unite things and bring them together; and he also claimed that it is a material principle inasmuch as he asserts that love is a part of compounds, since he assumed that bodies are compounds of the four elements and of friendship and strife. And even though the same principle can be both matter and a mover, it is not such under the same formal aspect. For fire can be a mover according to its form, and a material principle according to its matter; but it cannot be both in the same respect, because a mover as such is actual, whereas matter as such is potenial. Hence it must still be explained in what respect love has the character of a material principle, and in what respect it has the character of a moverand this he fails to do.
2647. Another incongruity which follows from Empedocles’ opinion is his positing strife as a first indestructible principle; for strife in itself seems to be essentially evil, and evil, in the opinions of those who are right, is not set down as a principle, but only the good, as has been stated (1109:C 2644).
2648. Again, Anaxagoras (1112).
Third, he turns to the opinion of Anaxagoras. He says that Anaxagoras makes the good to be a first principle of things as a mover; for he said that an intellect moves all things. But it is evident that “an intellect always causes motion for the sake of some goal,” i.e., an end. Hence Anaxagoras must posit some other principle by reason of which this intellect causes motion, unless perhaps he should say, as we have, that an intellect and its intelligible object can be the same; and that an intellect moves for its own sake; which is true in a sense of those things which act by intellect, according to our view. For the art of medicine acts for the sake of health, and health is in a sense the art of medicine itself, as has been pointed out above (C 2619; 606:C 1407).
2649. Another unreasonable consequence which is contrary to the opinion of Anaxagoras also seems to follow if the common view is maintained, namely, that contraries are the principles of all things. For according to this view it would be absurd for him not to make some principle contrary to the good and to intellect.
2650. But all who speak (1113).
He explains the third error which he noted above (1106-07:C 2639-40), namely, that those who held the principles to be contraries did not explain how things come from contraries as their principles. He says that all those who speak of contraries as principles fail to make use of them in accounting for what appears in the world, unless “some make use of imagery,” i.e., unless someone wishes to indulge his fancy or to speak figuratively.
2651. And none of them (ibid.).
First, he shows that they cannot account for the differences between destructible and indestructible things. He accordingly says that none of the ancient philosophers give any reason why some beings are destructible and some are not. Some of them claimed that all things are derived from the same principles, namely, contraries; and this is the opinion of the ancient natural philosophers. Others, the theological poets, held that all things come from non-being. Hence he said above (1065: C 2515) that they generate the world from non-being. And so although both groups assign the origin of all things, they cannot explain why things are distinguished into destructible and indestructible. Hence others, in order not to be driven to this, i.e., to posit that all things come from non-being or to account for the difference between things, held that all things are one, thereby entirely doing away with the distinction between things. This is the view of Parmenides and Melissus.
2652. Further, no one (1114).
Second, he shows that they were also wrong in another respect, namely, in being unable to explain why generation is eternal or to state what the universal cause of generation is; for neither of the contraries is a universal cause of generation.
2653. And those who (1115).
Third, he states how those men were wrong who claimed that the principles of things are contraries; for they must maintain that one of two contraries is a superior principle, since one contrary has the character of a privation. Or he means that it is necessary to posit some principle, which is more important than both contraries, by which it is possible to explain why certain things are attributcd to one of the contraries as their principle and why certain others are attributed to the other contrary; for example, why at one time strife will cause the elements to separate and why at another time friendship will cause them to combine.
2654. This difficulty also faces those who posit separate Forms; for they must assign some principle which is superior to the Forms, since it is evident that things which are generated and destroyed do not always participate in a form in the same way. Hence it is necessary to posit some principle by which it is possible to explain why this individual formerly participated or now participates in a form.
2655. And for other thinkers (1116).
Here he gives a fourth incongruity which faces these thinkers. He says that the philosophers who claim that the principles of things are contraries must admit that there is something contrary to the primary kind of wisdom or noblest science, because wisdom is concerned with the first principle, as has been shown in Book I (13:C 35). Therefore, if there is nothing contrary to the first principle (for all pairs of contraries have a nature which is in potentiality to each pair), and according to us the first principle is immaterial, as is clear from what has been said (1058:C 2495), then it follows that there is nothing contrary to the first principle, and that there is no science which is contrary to the primary science, but merely ignorance.
2656. Further, if nothing (1117).
Next, he turns to the opinion of those who posited separate substances. First, he points out that an incongruity faces those who fail to posit such substances. He says that, if nothing exists except sensible things, there will be no first principle, as has been noted (1055:C 2489), no order of things such as has been described, no eternal generation, and no principles of the kind which we have posited above (1060:C 2503); but every principle will always have a principle, and so on to infinity. Thus Socrates will be begotten by Plato and the latter by someone else and so on to infinity, as was seen to be the view of all of the ancient philosophers of nature. For they did not posit a first universal principle over and above these particular and sensible principles.
2657. Now if there (1118).
Then he shows that an unreasonable consequence faces those who posit certain separate natures. He does this, first, with regard to those who posited a certain connection in origin among natures of this kind; and second (1122:C 2661), with regard to those who did not hold this position (“And those who say”).
Concerning the first he draws out four untenable consequences. The first (1118) of these is that the separate Forms and numbers, which some posited over and above sensible things, seem not to be causes of anything. But if they are causes of something, it seems that nothing will be a cause of motion, because things of this kind do not seem to have the character of a moving cause.
2658. Again, how will (1119).
Second, he brings forward another incongruity. For number is not continuous quantity, but continuous quantity is constituted only of continuous quantities. Hence it seems impossible to explain how continuous quantity or extension comes from numbers, which are not continuous. For it cannot be said that number is the cause of continuous quantity either as a moving cause or as a formal cause.
2659. Further, no one (1120).
Then he gives the third untenable consequence. He says that, if the separate Forms and numbers are first principles, it follows, since contrariety is not found in forms and numbers, that first principles will not be contraries, because they are not held to be productive principles or movers. Hence it will follow that there is no generation or motion; for if the first principles are not efficient causes of motion but are subsequently caused from first principles, it will follow that they are contained in the potency of prior principles; and what can be can also not be. The conclusion, then, is that generation and motion are not eternal. But they are eternal, as has been proved above (1055:C 2490-91). Therefore one of the premises must be rejected, namely, the one holding that first principles are not movers. The way in which the first principles are movers has been stated in Book I (25-26:C 50-51).
2660. Again, as to the way (1121).
He gives the fourth incongruity. He says that none of these philosophers can state what it is that makes number, or soul and body, or in general form and the thing to which form belongs, a unity, unless he says that a mover does this, as we explained above in Book VIII (736:C 1759). Forms and numbers, however, do not have the character of a mover.
2661. And those who say (1122).
Here he indicates the unreasonable consequence facing those who claim that natures of this kind are unrelated things. He says that those who claim that mathematical number is the primary reality, as the Pythagoreans did, and “that there is always one substance after another” in this way, i.e., consecutively (so that after number comes continuous quantity, and after continuous quantity come sensible things), and who say that there is a different principle for each nature, so that there are certain principles for numbers, others for continuous quantity, and others for sensible things—those who speak in this way, I say, make the substances of the universe a group of substances unrelated to each other, i.e., without order, inasmuch as one part confers nothing on any other part whether it exists or does not. And they likewise make their many principles to be unrelated.
2662. Now this cannot be the case, because beings do not want to be badly disposed; for the disposition of natural things is the best possible. We observe this in the case of particular things, because each is best disposed in its own nature. Hence we must understand this to be the case to a much greater degree in the whole universe.
2663. But many rulers are not good. For example, it would not be good for different families which shared nothing in common to live in a single home. Hence it follows that the whole universe is like one principality and one kingdom, and must therefore be governed by one ruler. Aristotle’s conclusion is that there is one ruler of the whole universe, the first mover, and one first intelligible object, and one first good, whom above he called God (1074:C 2544), who is blessed for ever and ever. Amen.