LECTURE 13 (259 a 22-260 a 19)

THE FIRST MOVER IS ETERNAL AND IMMOBILE. THE FIRST MOTION IS ETERNAL

1077. After the Philosopher has shown that the first mover is eternal and totally immobile by means of an argument derived from the eternity of the generation and corruption of animals which move themselves, he here intends to prove the same thing by means of an argument derived from moving principles.

             Concerning this he makes three points. First he summarizes what has been said at the beginning of this treatise. Secondly, where he says, 'Hence we may confidently . . .' (259 b 20), he develops from the above a proof of his position. Thirdly, where he says, 'The foregoing argument . . .' (260 a 11), he answers a difficulty which was raised above.

             1078. He summarizes three points, the first of which is a rejection of certain improbable positions.

             He says that not only from the foregoing but also from a consideration of the principles of motion one can conclude that there is a first immobile mover. As was said above, it is clear to the senses that some natural things are found to be sometimes moved and sometimes at rest.

             From this it was shown above that none of these three positions is true: all things are always moved; all things are always at rest; all things which are at rest are always at rest and all things which are moved are always moved. For things which are found in both states, that is, in motion and at rest, demonstrate the truth in this matter, for they have the potency to be sometimes moved and sometimes at rest.

             1079. Secondly, where he says, 'The existence of . . .' (259 a 26), he recalls the procedure used above to investigate the first immobile mover.

             He says that things which are sometimes moved and sometimes at rest are obvious to all. But someone might develop a fourth position by saying that all beings are such that they are sometimes moved and sometimes at rest. Hence we wish to demonstrate a double diversity in nature by showing that there are certain things which are always immobile and other things which are always moved.

             In doing this we held first that whatever is moved is moved by something. And that by which a thing is moved must be either immobile or moved. If it is moved, it is moved either by itself or by another. And since there is not an infinite series of movers, it is necessary to arrive at some first principle of motion. Hence, in the genus of things which are moved there is a first principle which moves itself. Furthermore, among all things the first principle is that which is immobile. And it should not be thought to be inconsistent that a thing moves itself, for we clearly see many such beings in the genus of living things and of animals.

             1080. Thirdly, where he says, 'This being so, . . .' (259 b 3), he recalls a difficulty which he raised and answered above.

             When he proved the eternity of motion, he raised an objection to the contrary dealing with living beings which, although they were previously at rest, at some time begin to be moved. He says that living beings which move themselves seem to indicate that in the whole universe motion comes to be when previously it was not. For in living things we see that at some time they begin to be moved when previously they were not moved.

             To answer this difficulty it must be understood that animals move themselves with respect to one motion, namely local motion. For only this motion is found to be subject to appetite in animals. Nevertheless, animals do not properly move themselves with respect to this motion such that no other cause of this motion pre-exists. For the first cause is not in animal itself which is moved locally. Rather other natural, nonvoluntary motions precede, either from within or from without, with respect to which animals do not move themselves. This is clear in regard to the motions of increase and decrease and breathing with respect to which animals are moved, even though they are at rest with respect to local motion, by which they are moved by themselves.

             Moreover, the cause of these natural motions is either the extrinsic container, namely, the heavens and the air, by which animal bodies are altered from the exterior, or else it is something which enters animal bodies, as air enters in breathing, and as nourishment enters through eating and drinking. From transmutations of this kind, whether they result from interior or exterior causes, animals which previously were at rest at some time begin to be moved. This is clear in regard to the transmutation resulting from nourishment. For while nourishment is being digested, animals sleep because of the vapours which are released. But when nourishment has been digested and assimilated and the vapours have settled, animals awaken, and rise, and move themselves locally. Nevertheless, the first principle of the motion is something extrinsic to the nature of the animal which moves itself.

             Hence animals are not always moved by themselves. For in respect to any animal which moves itself, there will be found some other prior mover which is moved and moves. For if this mover were totally immobile, it would always be related to moving in the same way, and thus animal motion would be eternal. But since this external mover which moves animals is itself moved, it does not always move in the same way.

             Hence animals do not always move themselves in the same way. For in all animals the first mover which is the cause of the animal's self-motion, that is, the soul, so moves that it is moved, not indeed per se, but per accidens. For when the body is changed with respect to place, then that which exists in the body, that is, the soul, is changed per accidens. Hence, the whole self-mover is necessarily changed so that it is not in the same disposition for moving.

             1081. Next where he says, 'Hence we may confidently . . .' (259 b 20), he proves his position from the foregoing.

             First he shows that the first mover is immobile. Secondly, where he says, 'And further, if there . . .' (259 b 32), he shows that the first mover is eternal.

             Concerning the first part he makes two points. First he proves his position. Secondly, where he says, 'We must distinguish . . .' (259 b 27), he rejects an objection.

             He says, therefore, first that from the foregoing we can show that an immobile moving principle which is moved per accidens cannot cause continuous and eternal motion. The reason why the souls of animals do not always move is that they are moved per accidens. But it was shown above that the motion of the universe must be continuous and eternal. Therefore, the first moving cause in the whole universe must be immobile, such that it is not even moved per accidens.

             Just as there ought to be an imperishable and unceasing motion in natural things, as was said above, so also the whole of being, that is, the disposition of this universe, remains in its own disposition and in the same state. For from the immobility of the principle which is given as remaining immobile, it follows that the whole universe has an eternal permanence insofar as it is continuous with the first immobile principle by receiving influence from it.

             1082. Next where he says, 'We must distinguish . . .' (259 b 27), he rejects an objection.

             He has said that if a mover is moved per accidens, it does not move with an eternal motion. But there seems to be an exception to this. For according to his position the motions of the lower orbs, for example, the sun and the moon and the other planets, are eternal. Nevertheless their movers seem to be moved per accidens, if we follow what he said earlier. For in this latter argument he said that the animal soul is moved per accidens because the animal body is moved as a result of some other motion from an external principle, which motion is not from the soul. Similarly, it appears that the sun is moved by some other motion, as if transferred from the motion of the first orb, with respect to which it is revolved from east to west. However, by that motion it is not moved by its proper mover, but conversely from west to east.

             He rejects this objection by saying that to be moved per accidens can be attributed to a thing either with respect to itself or with respect to another, and these are not the same. Therefore, to be moved per accidens can be attributed to the movers of the planets, not such that they themselves are moved per accidens, but such that the orbs moved by them are moved per accidens, which motion is transferred from the motion of the higher orbs. He says that to be moved per accidens by another, that is by reason of another, is present in certain principles of celestial motions insofar as the movers of the orbs are moved by many motions, namely by their proper motion and by the motion of a higher orb. But the other, namely, to be moved per accidens with respect to itself, is found only in corruptible things, that is, in besouled animals.

             The reason for this diversity is that the movers of the higher orbs are not constituted in their being by a union to bodies, and their connection is invariable. Therefore, although the bodies of the orbs are moved, their movers are not moved per accidens. But the souls which move animals are constituted in their being by a union to bodies, and they are connected with them in various ways. Therefore, with respect to mutations of bodies, these souls are also said to be changed per accidens.

             1083. Next where he says, 'And further, if there . . .' (259 b 32), he proves that the first motion is eternal. He does this with two arguments, the first of which depends on the foregoing, and is as follows.

             Motion which is not eternal is due to a mover which is moved per se or per accidens, as is clear from the above. Since, then, the first mover is immobile and eternal such that it is not moved either per se or per accidens, the first mobile object that is moved by this totally immobile mover must be moved eternally.

             It must be noted, however, that above he proved the immobility of the first mover through the eternity of the motion designated above. Here, however, he conversely proves the eternity of motion through the immobility of the first mover. He would be arguing in a circle if he were referring to the same motion.

             Hence, it must be said that above he proved the immobility of the first mover from the eternity of motion in general. Therefore, he said that in things which exist there is a certain unceasing and imperishable motion. Here, however, he proves the eternity of the first motion through the immobility of the first mover. From this it is clear that the Commentator is incorrect when he says that above in the beginning of Book VIII Aristotle proved that the first motion is eternal.

             1084. He gives the second proof where he says, 'Indeed this is clear also . . .' (260 a 2). This argument deals with the eternity of generation.

             He says that it is clear that the first motion is eternal because there cannot be generation and corruption and non-temporal mutations unless there is something which moves and is moved. For every mutation results from some mover, as he has already proved above. Therefore, generation and corruption and such mutations must result from some mover.

             However, these cannot result immediately from an immobile mover. For an immobile mover will always move the same moved object in the same way since it will not change its disposition and relation to the mobile object. And when the relation of the mover to the mobile object remains the same, the motion will always remain the same. But generation and corruption do not always occur in the same way. Rather at one time a thing is generated, and at another it is corrupted. Hence these do not proceed immediately from an immobile mover, but from a mobile mover. That which is moved by a moved mover, which in turn is moved by an immobile mover, can have a perpetual succession of diverse motions. For since a mobile mover is related in different ways to moved things, it will not always cause the same motion. Rather, because it is in diverse places (if it is moved by local motion) or in diverse species (if it is moved by the motion of alteration), it will cause contrary motions in others, and it will cause a thing to be sometimes moved and sometimes at rest.

             He says that it '. . . occupies contrary positions or assumes contrary forms . . .' (260 a 8) because he has not yet proven by what species of motion the first mobile object is moved. He will investigate this below.

             Therefore, insofar as it is moved, it is the cause of the diversity of motions. But insofar as it is moved by an immobile mover, it is the cause of eternity in this diversity of mutations. Therefore, the eternity of generation shows that the first motion is eternal and is moved by an immobile mover.

             It should be understood, however, that these arguments, with which Aristotle strives to prove that the first motion is eternal, do not come to a necessary conclusion. For it may happen, without any mutation of the first mover, that it does not always move, as was shown above at the beginning of Book VIII.

             1085. Next where he says, 'The foregoing argument . . .' (260 a 11), he introduces a conclusion for that which he left unanswered above, namely, why are certain things always moved, while others are not always moved.

             He says that the cause of this is clear from the foregoing. For things which are moved by an immobile and eternal mover are always moved. But things which are moved by a moved mover are not always moved. For as was said above, since an immobile mover remains simply and similarly in the same disposition, it will cause a motion that is one and simple.