Lecture 1 — The heaven is eternal and its motion endless and without labor. Contrary opinions excluded

213 That the heaven as a whole neither came into being nor admits of destruction, as some assert, but is one and eternal, with no end or beginning of its total duration, containing and embracing in itself the infinity of time, we may convince ourselves not only by the arguments already set forth but also by a consideration of the views of those who differ from us in providing for its generation. If our view is a possible one, and the manner of generation which they assert is impossible, this fact will have great weight in convincing us of the immortality and eternity of the world.

214 Hence it is well to persuade oneself of the truth of the ancient and truly traditional theories, that there is some immortal and divine thing which possesses movement, but movement such as has no limit and is rather itself the limit of all other movement.

215 A limit is a thing which contains; and this motion, being perfect, contains those imperfect motions which have a limit and a goal, having itself no beginning or end, but unceasing through the infinity of time, and of other movements, to some the cause of their beginning, to others offering the goal.

216 The ancients gave to the Gods the heaven or upper place, as being alone immortal;

217 and our present argument testifies that it is indestructible and ungenerated. Further, it is unaffected by any mortal discomfort,

218 and, in addition, effortless; for it needs no constraining necessity to keep it to its path, and prevent it from moving with some other movement more natural to itself. Such a constrained movement would necessarily involve effort the more so, the more eternal it were—and would be inconsistent with perfection.

219 Hence we must not believe the old tale which says that the world needs some Atlas to keep it safe—a tale composed, it would seem, by men who, like later thinkers, conceived of all the upper bodies as earthy and endowed with weight, and therefore supported it in their fabulous way upon animate necessity. We must no more believe that

220 than follow Empedocles when he says that the world, by being whirled round, received a movement quick enough to overpower its own downward tendency, and thus has been kept from destruction all this time.

221 Nor, again, is it conceivable that it should persist eternally by the necessitation of a soul.

222 For a soul could not live in such conditions painlessly or happily, since the movement involves constraint, being imposed on the first body, whose natural motion is different, and imposed continuously. It must therefore be uneasy and devoid of all rational satisfaction; for it could not even, like the soul of mortal animals, take recreation in the bodily relaxation of sleep. An Ixion's lot must needs possess it, without end or respite.

223 If then, as we said, the view already stated of the first motion is a possible one, it is not only more appropriate so to conceive of its eternity, but also on this hypothesis alone are we able to advance a theory consistent with popular divinations of the divine nature. But of this enough for the present.

288. After having determined in Book I concerning the world as a whole, in which he showed to exist some bodies that are circularly moved and some that are moved with a straight motion, the Philosopher here begins to determine about the bodies that are circularly moved.

First he determines the question of the bodies themselves that are circularly moved;

secondly, he determines the question of the center about which they are circularly moved, at it remains to speak of the earth (L. 20; 293a15).

As to the first he does two things:

first, he discusses the heaven, which is the circularly moved body;

secondly, the stars which are in the heaven, at we have next to speak of the stars (L. 10; 289a11).

About the first he does two things:

first, he determines what pertains to the substance of the heaven;

secondly, what pertains to its motion, at since there are some who say (L. 7; 287b22).

As to the first he does three things:

first he determines about the duration of the heaven;

secondly, about the variety of its parts, at now there are two ways (L. 2; 284b6);

thirdly, about its shape, at the shape of the heaven (L. 5; 286b10).

Regarding the first he does two things:

first he draws a conclusion made clear in what has gone before;

secondly, from that conclusion he argues to his proposition, at hence it is well to persuade oneself (284a2; [290]).

289. He says therefore first (283b26) that from what has gone before [Ll. 22 ff. of book I], we can believe that the entire heaven neither was made nor is able to be corrupted as some say. He says that the whole heaven is ungenerated and indestructible on the ground that the major part of the bodies of the world is the substance of heavenly body, which is neither generated nor destructible, in the sense explained in book I. Or else he is saying this to differentiate it from those parts of the world that are generable and destructible with respect to their parts, although not wholly, as is plain in the elements. Or else because those bodies which are generable and destructible, for example, plants and animals and stones, are not in the strict sense parts of the world (otherwise the world would never be perfect, since it would never possess all such things at once); rather they are effects of the parts of the world. Therefore, although such things are subject to generation and corruption not only with respect to a part but also as a whole, nevertheless the whole world is neither generated nor corrupted. It should be noted that he says the whole heaven was not generated, and then, instead of saying, "it is not corrupted," he says, it cannot be corrupted. He uses this way of stating it for the sake of those who said that the world is of its very nature corruptible but that on account of God's will it never will be corrupted. He therefore specifically says, as some say.

But it has been proved above that the world is one only and eternal (which he says lest anyone suppose that the eternal be not numerically one but one in species only), in such a way as to have neither a beginning nor an end of the whole eternal, i.e., of its whole infinite duration. Now, lest anyone suppose that he means the corporeal world is eternal as God is eternal, Whose existence and life are totally all at once, i.e., without any succession of before and after, he adds that the world possesses an infinitude of time, since, namely, its duration extends according to the succession of time. Yet the whole world does not possess temporal duration in the same way as some generable and destructible singular, whose duration is comprehended. by time but does not encompass time; rather time is encompassed by the whole world, both because time does not extend beyond the duration of the world and because time is produced from the motion of the first body of the world, as was explained in Physics IV. Thus time is contained by the world as an effect by its cause. Now time is the measure of a celestial motion not through the latter's being contained by it as an effect by its cause (for the container is not measured by the content, but the other way around), but through its being a certain image of God's eternity as Boethius says, who dost command time to proceed from the aeon.

Therefore the foregoing statements are worthy of belief not only on account of the arguments previously cited, but also on account of the contrary opinions of those who attribute generation and corruption to the world. For if the world turns out to be as we have described it, with no paradoxes arising, and it cannot have come about in the manner described by those who claim that the world was generated, then our description will have a great inclination, i.e., great power to persuade one to believe in the immortality of the heaven and in its eternity—where immortality refers to the perpetuity of life and eternity to the perpetuity of its existence—for they maintained that the heaven not only existed but also lived, as something animated.

From what he says here, it is plain that Aristotle presented his previous arguments in proof of the eternity of the world not with the intention of showing with necessity that the world could not have begun but as showing that it did not begin in the manner described by others.

290. Then, at hence it is well to persuade oneself (284a2), from the preceding conclusion as to the eternity of the entire world, he concludes to his proposition, namely, to the eternity of the heavenly body. And concerning this he does three things:

first he infers the conclusion in a general way;

secondly, he explains it in detail, at the ancients gave to the gods (284a11; [292]);

thirdly, from the truth shown he excludes certain contrary opinions, at hence we must not believe (284a18; [295]).

About the first he does two things:

first he draws his intended conclusion;

secondly, he presents its argument, at a limit is a thing (284a6; [291]).

He says therefore first (284a2) that, because we are inclined to believe in the eternity of the world from what has preceded, it follows that a man shows himself easily persuasable by the dictums of the ancients — not, however, by those of any who erred but principally by those of our fathers, who, namely, schooled us in divine worship. We should be inclined to believe their words to be true, to the effect that there is something immortal and divine, not only among the number of the immobile substances, which are totally separated from matter, but also among bodies which have motion, such, however, that of the motion of the divine and immortal body there be no end, by which, namely, it might be terminated; rather its motion is the end of all other motions. Now the reason he attributed this to the ancient sayings of the ancestors is because all those who established a form of divine worship among the gentiles sought to have divine worship given to the heaven as to a divine and immortal body whose motion is endless. Accordingly they derive from theirs, which means "to run forever," their name for the deity, theos.

291. Then, at a limit is a thing (284a6) he presents his argument for that part of the foregoing conclusion which stated that the motion of the heaven is the end of other motions. For everything that contains has the notion of end inasmuch as the contents end at the limits of the container. Now, it is clear that the imperfect is disposed to be contained by the perfect. As was proved in book I, circular motion is perfect and straight motions imperfect, for these do not return to their beginning as a circular motion does; rather their terminus is most remote from the beginning and contrary to it—wherefore, just as they begin to move at the start, so, they begin to rest when at the end. Consequently, circular motion must contain other motions as the perfect contains the imperfect. And for this reason circular motion is the end of other motions, in such a way, namely, that the former has neither a beginning nor an end at which to start or cease; rather, it moves without cease in infinite time. For whatever begins or ceases to be moved, does so under the influence of some previous motion, which is the cause of its motion. If the mover and moved were in the same relationship, there would be no more reason for a motion to begin later than before. Hence, if some motion begins newly, there must pre-exist some motion to cause the newness of this motion. Now if the world is eternal, motion would have to have always been. Hence it was necessary to posit some eternal motion which would contain other motions that were not eternal and be their end in such a way as to be a cause of motion in these mobiles which begin to be moved, and to receive the rest of those which cease to be moved. He does not say "causes the state of rest" but receives, because a universal cause aims at impressing its likeness on its effects which, however, cannot be equated to the universal cause but receive its likeness according to their condition. Thus lower things do not uniformly receive from God the eternity of the divine being so as to remain forever the same in number, but they remain the same in species through the generation and corruption of individuals. Hence God gives existence to things but receives their corruption, using it, as it were, for the generation of other things. In like manner, the lower motions receive a likeness of the eternity of the heavenly motion not in a uniform manner but according to the alternation of motion and rest. Here, whatever there is in them of motion is caused by the heavenly motion; but whatever is in them of defect of motion, i.e., of rest, is due to their defect, because it is not in their nature to be in eternal motion. So the motion of the heaven is said to accept the state of rest of these bodies as something ordained to an end. Wherefore Plato in the Timaeus has God, the establisher of the world, saying to the heavenly gods: make things increase by giving food and take back once more the things that suffered loss.

292. Then, at the ancients gave to the gods (284a11) he explains in detail what he had said:

first, as to the eternity of the heaven;

secondly, as to the quality of its motion, at and, in addition, effortless (284a18; [294]).

That the heaven is eternal he shows in two ways.

First, from the sayings of the ancients. He says that they assigned to the gods the heaven and the place which is above, taking the heaven as immortal and suitable as a place for immortal beings, as was also stated above in book I. And he gives to the place above the name "heaven" in keeping with the common opinion of those so speaking and also because the place whither light things are borne, and which is properly called an upward place, is nearest to the heavenly body.

293. Secondly, and our present argument testifies (284a13) he explains it with a reason previously cited, which showed the heaven to be ungenerable and indestructible from the fact that it has no contrary. It was also shown there that the heaven is impassible, with the passion that produces difficulty of corruption. Heavenly bodies are, however, passible with a perfective passion, as in the case where the moon is illuminated and receives virtue from the sun. These things, too, were previously mentioned.

294. Then, and, in addition, effortless (284a14) he shows the quality of the heaven's motion, namely, that it is moved without labor. This he proves on the ground that there can be posited no violent necessity that would keep it from being moved otherwise, i.e., according to its nature. For whatever is moved with labor is being moved against the natural motion of its body—for which reason it is laborious for an animal to move upwards. Now in the case of things moved against their nature, if such a motion is to continue, it must be maintained by some violent mover imposing on them a motion of coercion—for natural necessity leads only to what is according to nature. Everything such, i.e., which is subject to a motion contrary to its nature, must be in more and more labor accordingly as the motion is more continuous and eternal, and as it is more alien to its best disposition, i.e., that which is according to its nature. But such a thing cannot happen to the heavenly body, which is the noblest of bodies. Consequently, the motion of the heaven is not laborious.

295. Then, at hence we must not believe (284a18) he excludes contrary opinions.

First, he dismisses certain errors;

secondly, he concludes to the truth intended, at if then, as we said (284a35; [299]).

With respect to the first he dismisses three opinions.

The first of which is a fable. And he says (284a18) that because the motion of the heaven is neither laborious nor contrary to nature, no one should even slightly suspect that the eternity of the heaven and of its motion are as the ancient fables of Homer and other poets describe them. They said that the heaven, to be kept in its position, requires a giant they named Atlas, who stands upon two pillars and supports the world on his shoulders. Now the ones who originated that fable seem to have held the same opinion about celestial bodies as some later teachers, namely, that they were heavy and earthy, and as such had to be held up against their nature by animate power, or that of some living things, such as God or a separated substance of some kind. And if they maintain that this is necessary on the ground that the heaven has weight, the fable is wholly to be rejected. However, if they mean that the heaven has by nature such-and-such a position and motion, but that its nature was produced and is conserved by another, then the fable contains something divine.

296. Secondly, at than follow Empedocles (284a24) he rejects the opinion of Empedocles who posited that the heaven is kept in its position that prevents it from falling by the rapidity of its motion which overcomes its natural inclination to fall—as occurs with water, which will not spill if the vessel of water is rotated more rapidly than the motion of the water downward. Democritus and Anaxagoras are also said to have held this. Now this could perhaps happen for a short time, but that through such a speed of motion the heaven should keep its position for so great a time, namely, an infinite and perpetual time, is most unprovable. For since that which is violent is a certain exorbitation [departure] from what is according to nature, it does not seem that what is by violence could last longer than what is according to nature—since what is according to nature occurs, as it were, always, or for the most part. These latter, like the first, seem also to base their argument on the supposition that heavenly bodies have weight but are prevented from falling downward by the rapidity of their motion.

297. Thirdly, at nor, again, is it conceivable (284a27) he rejects a third opinion, that of Plato, who says in the Timaeus that in the center of the world, its soul, reaching to the extremity of the heaven and everywhere, began an imperishable and wise life for all time.

First he rejects this opinion on the part of the body. Hence he says that it is not reasonable to say that the heaven and its motion remain forever on account of the compulsion of the rational soul, because nothing forced can last forever, for, since compulsion is against nature, it would follow that what is according to nature would never exist.

298. Secondly, at for a soul could not (284a28) he shows the same on the part of the soul. And he says that the life of the soul so moving a body cannot be without sadness and happy. For since the motion of the body is caused by compulsion and the soul moves that body circularly, which is inclined to be moved otherwise, and in addition moves this body continually, then of necessity that soul is never free and is removed from all prudent strength. Now prudent strength can refer to the operation of the speculative intellect, which requires prudence and strength, as though [Aristotle] were saying, "If the soul of heaven can in no way find relief from the labor it undergoes in moving the heaven against its nature, it will always be kept from vehement contemplation, which its uninterrupted labor and consequent sadness prevent." Or "prudent strength" could refer to the effort the soul applies in order to keep things moving according to prudence. For it does not seem to be in keeping with prudence to apply its strength without ceasing to some task. For if laborious work is undertaken for a short time, it will be tolerable; but the heaven is moved with a continual and eternal motion. Hence if the soul of the heaven were to move the heaven against its nature in a laborious manner, it would follow that that soul would be worse off than the souls of mortal animals, which get rest from moving the body at least during sleep. But it is necessary that fate, i.e., the decree of some superior being keep the soul of the heaven eternal and indestructible, i.e., unfailing in moving, after the manner of a certain man called Ixion, who, the fables tell us, while acting as steward at Juno's wedding, lusted after her. But she substituted for herself a cloud, from which he begot the Centaur. For this he was condemned by Jupiter to be bound to a wheel on which he continually revolves. This Aristotle seems to say against the statement of Plato who asserted that from the center of the world unto the outermost heaven the soul everywhere complex began an unceasing and prudent life for all time. For this would appear to be no different than being bound to the heaven as Ixion to the wheel. And it seems that the life of such a soul is not prudent but foolish, as undertaking an endless labor. However, Aristotle is not here reprehending Plato for positing an animate heaven—because later on he does the same—but for seeming to suppose that this soul is moving the heaven forever contrary to its nature. But perhaps Plato did not understand this motion as contrary to the nature of the heaven but wanted to bring out that the nature according to which this motion befits it is in it from another.

299. Then, at if then, as we said (284a35), he concludes from the foregoing that if our account of the first local motion, which is the heavenly motion, is correct, namely, that it is without labor, not only is to think this better from the point of view of the eternity of the heaven, but it is also more in conformity with out estimate of the gods—which he calls divination, as though had by divine revelation. For that is the only way to keep our teaching consistent, since it does not appear congruent to say on the one hand that the heaven is being moved by God, and to say on the other that its motion is laborious. But this is enough on such matters for the present.