LECTURE 10 (230 a 19-231 a 18)

CERTAIN DIFFICULTIES ARE ANSWERED

             737. After the Philosopher has treated the contrariety of motions and of states of rest, he here raises certain difficulties concerning the foregoing.

             Concerning this he makes two points. First he states the difficulties and answers them. Secondly, where he says, 'With regard to coming . . .' (231 a 5), he mentions certain clarifications, which clarifications are open to question.

             The first part is divided according to the three difficulties which he raises. These divisions are clear in the text.

             Concerning the first difficulty he makes two points. First he states the difficulty. Secondly, where he says, 'We answer that if . . .' (230 a 29), he answers it.

             738. First he states the difficulty. Why is it that in the genus of local motion some motions and some states of rest are found to be natural and some unnatural, while this is not found in the other genera of motion? For example, why is not one alteration natural and another unnatural? Becoming healthy does not seem to be more natural or unnatural than becoming sick, for each of these proceeds from a natural, intrinsic principle.

             The same problem arises with becoming white and becoming black and with increase and decrease. Neither of the former motions is contrary to the other in such a way that one is natural and the other unnatural. For each of them occurs naturally. And one increase is not contrary to another in such a way that one is natural and the other unnatural.

             The same argument applies to generation and corruption. It cannot be said that generation is natural and corruption unnatural. For growing old, which is the road to corruption, occurs naturally. Furthermore, we do not observe that one generation is natural and another unnatural.

             739. It seems that what he says here is contrary to what he says in De Caelo, II; namely, that old age and every defect and corruption is contrary to nature.

             But it must be said that old age and corruption and decrease in a way are contrary to nature and in a way are in accord with nature.

             For if one considers a thing's proper nature, which is called its particular nature, it is clear that every corruption and defect and decrease is contrary to nature. For the nature of each thing tends toward the conservation of its proper subject. And the contrary results from the defect and weakness of the nature.

             But if one considers the nature universally, then all such things arise from some natural, intrinsic principle. For example, the corruption of an animal arises from the contrariety of hot and cold. And the same explanation applies to the other cases.

             740. Next where he says, 'We answer that if . . .' (230 a 29), he answers this difficulty by destroying it.

             Concerning this he makes two points. First he shows that natural and unnatural motion is found in every genus. Secondly, where he says, 'Now motions and states . . .' (230 b 10), he shows how the natural and the unnatural in motions and in states of rest are contrary.

             Concerning the first part he makes two points. First he establishes the truth. Secondly, where he says, 'But, it may be objected . . .' (230 b 6), he answers an objection.

             He says, therefore, that that which occurs by violence is unnatural. (For the violent is that whose principle is extrinsic, and that which is changed contributes none of the force. But the natural is that whose principle is intrinsic.) Hence it follows that violent corruption is contrary to natural corruption as unnatural corruption is contrary to natural corruption.

             And for the same reason he concludes that certain generations are violent and not according to fate; that is, they do not proceed according to the order of natural causes. (The order of natural causes can be called fate.) This clearly occurs when one produces roses or some kind of fruit by artificial means at an unusual time. Another example is when frogs or some other natural beings are generated by artificial means. Since these generations are violent, they are consequently unnatural and contrary to natural generations.

             Next he shows the same thing in regard to increase and decrease. Some increases are violent and unnatural. For example, some people mature more quickly than usual because of their softness and their food; that is, because they are nourished by wholesome and abundant food. The same thing occurs in the growth of wheat. For grain grows unnaturally when there is an abundance of ground and when by proper distribution it is not closely and densely packed down.

             The same thing occurs in alterations. Some alterations are violent and some natural. This is especially clear in becoming cured. Some people lose their fever during the non-critical days. These people are altered unnaturally. Others lose their fever during the critical days. These are altered naturally.

             741. Next where he says, 'But it may be objected . . .' (230 b 6), he objects to the above.

             That which is unnatural is contrary to that which is natural. Hence, if there be natural and unnatural generation, and likewise corruption, it follows that corruptions are contrary to each other and not to generation. For one thing cannot be contrary to two things.

             He answers this by saying that there is nothing to prevent generation from being contrary to generation, and corruption to corruption. This is true even if there would be no contrariety of natural and unnatural. For if one generation or corruption is pleasant and another harsh, then generation must be contrary to generation and corruption to corruption.

             Generation and corruption are called pleasant when the more noble is generated from the corruption of the less noble. For example, fire is generated from the corruption of air. Generation and corruption are called harsh when the less noble is generated from the corruption of the more noble. For example, air is generated from fire.

             But if corruption is opposed to corruption, it does not follow that it is not opposed to generation. For corruption is opposed to generation according to the nature [ratio] of its own genus. But corruption is opposed to corruption according to the nature [ratio] of a proper species. Thus, avarice is opposed to liberality according to the contrariety of vice to virtue. But it is opposed to prodigality according to the nature [ratio] of a proper species. He concludes that corruption is not contrary to corruption simply, that is, universally. Rather, one corruption is of one type, and the other of another type; that is, violent and unnatural, or pleasant and harsh.

             742. Next where he says, 'Now motions and states . . .' (230 b 10), he shows how there is contrariety in motion and in rest in respect to that which is natural and unnatural.

             He says that not only is generation contrary to generation and to corruption in respect to what is natural and unnatural, but all motions and states of rest are contrary in this way. For example, upward motion is contrary to downward motion (for up and down are contraries of place). And each of these motions is natural to some body. For fire is naturally borne upwards and earth downwards. Further, for each of these motions there are different contraries in respect to what is natural and unnatural. This is what he means where he says, '. . . the locomotions of the two are contrary to each other' (230 b 13).

             Or this could mean that the bodies themselves which are moved have different contraries of motion in respect to what is natural and unnatural. For upward motion is natural to fire, but to be moved downwards is unnatural to fire. Thus it is clear that natural motion is contrary to unnatural motion.

             The same applies to states of rest. For rest in an upward state is contrary to motion from up to down. But such a state of rest is unnatural to earth, and downward motion is natural. Hence, according to the foregoing it is clear that an unnatural state of rest of a body is contrary to its natural motion. In regard to the same body motions are also contrary to each other in such a way that the natural motion of the body is contrary to its unnatural motion. And it is the same with states of rest. For one of the contrary states of rest will be natural; for example, up for fire and down for earth. And the other will be unnatural, for example, down for fire and up for earth.

             743. Next where he says, 'Here, however, the question arises . . .' (230 b 21), he raises the second difficulty. Is there a generation for every state of rest which has not always existed? This generation of a state of rest is called a 'coming to a standstill' [stare]. This is done so that we will not understand 'coming to a standstill' and 'being at rest' [quiescere] to mean the same thing. Rather 'coming to a standstill' means 'to arrive at a state of rest'. This perhaps sounds better in the Greek.

             He seems to answer this question in the negative with two arguments.

             The first is that, if there is a generation for every state of rest which has not always existed, then it follows that there is generation of an unnatural state of rest (as when earth is in an upward state of rest). But rest can be generated only by a preceding motion. And the motion which precedes an unnatural state of rest is a violent motion. Thus it would follow that when earth was violently borne upwards, its state of rest was generated. But this cannot be. For when a state of rest is being generated by motion, the motion always becomes faster in proportion as it approaches the state of rest. For the generated thing is the perfection of the generation. And insofar as anything is closer to its perfection, it is proportionately more powerful and more intense. Hence it follows that the motion by which rest is generated becomes proportionately faster as it approaches nearer to the state of rest. This is quite clear in natural motions.

             But in things that are moved by violence the opposite occurs. For they are always found to be proportionately more remiss as they approach nearer to the state of rest. Therefore, a violent state of rest has no generation. And thus he says that a thing will be violently in a state of rest without this state of rest having been generated.

             744. He gives the second argument where he says, 'Moreover, "coming to a standstill" . . .' (230 b 26). The argument is as follows. 'Coming to a standstill,' or the generation of rest, is either altogether the same as the natural motion by which a thing is borne to its proper place, or else occurs together with this motion.

             It is clear that these are the same in subject but different according to reason [ratio]. For the terminus of natural motion is to be in the natural place. And to be in the natural place and to be at rest there are the same in subject. Hence natural motion and the generation of rest are the same in subject, and they differ only in reason [ratio]. Moreover, it is clear that a violent state of rest is not generated by natural motion. Therefore, a violent state of rest has no 'coming to a standstill' or generation.

             745. Next where he says, 'There is also another . . .' (230 b 27), he raises the third difficulty concerning what was said above; namely, that rest in a terminus is contrary to the motion which recedes from that terminus.

             This seems to be false. For when someone is moved from a terminus in place, or when a terminus of quantity or quality is being abandoned, then, while one is being moved, one seems to have that which is being abandoned or deserted. For the total place is not left behind suddenly, but successively. And likewise one loses whiteness successively. Hence, while one is being moved, one still remains in the terminus from which. Therefore, if the rest by which something remains in the terminus from which is contrary to the receding motion, then it would follow that two contraries exist together. This is impossible.

             746. He answers this difficulty where he says, 'May we not say . . .' (230 b 33).

             He says that that which is moved by receding from a terminus rests in that terminus from which it recedes, not simply, but in a qualified sense. That is, it remains in that terminus partially but not totally. For it is universally true that one part of that which is moved is in the terminus from which and another part is in the terminus to which. And it is not impossible for one contrary to be mixed with the other contrary in a qualified way. But the more unmixable they are, the more contrary they are. Therefore, motion is more contrary to motion, with which it is never mixed, than is rest, which is mixed with motion in a certain way.

             Lastly he concludes that he has now stated how unity and contrariety are found in motion and in rest.

             747. Next where he says, 'With regard to coming . . .' (231 a 5), he gives some clarifications of the foregoing. However these points are said to be not included in the Greek texts. And the Commentator says that they are not found in some of the Arabic texts. It seems rather that these remarks are taken from the writings of Theophrastus or some other commentator on Aristotle.

             Nevertheless three things are stated here to clarify the foregoing.

             The first of these pertains to the difficulty raised above concerning the generation of an unnatural state of rest. He says that one might raise a problem about 'coming to a standstill'; that is, the generation of rest. If all motions which are unnatural have an unnatural state of rest, is that state of rest generated? If it be said that there is no 'coming to a standstill' for a violent state of rest, then an impossibility follows. For it is clear that that which is moved by violence will remain at rest by violence. From this it would follow that a thing could be not always at rest, without its state of rest having come into being. This seems to be impossible. But it is clear that at times there are violent states of rest. For just as things are moved unnaturally, also things are at rest unnaturally.

             Moreover it must be noted that what is said here seems to be contrary to what was said above. Hence Averroes says that the difficulty raised above is answered here.

             But it is better to say that that which was stated above is more true, even though that which is said here is true in a certain way. For a violent state of rest does not properly have a generation which proceeds from a cause which per se produces the state of rest. This is how a natural state of rest is generated. Rather it has a per accidens generation by means of a defect in the producing power. For a violent state of rest occurs when the violence of the mover ceases or is impeded. Therefore, violent motion is decreased at the end, while natural motion is increased at the end.

             Furthermore, it must be realized that there is another version of the text here which has a different meaning. This version is the following: one might ask whether there is an unnatural state of rest which is contrary to unnatural motion.

             The meaning here is not that unnatural rest is properly opposed to unnatural motion, as Aristotle teaches above. Rather he is speaking here generally and improperly about the common opposition of rest to motion.

             He says that it seems irrational if there be no unnatural rest. For it is clear that the violence of the mover will cease at some time. And unless some state of rest consequently results, the motion will not arrive at any 'standstill'. Thus it is clear that a violent state of rest is opposed to violent motions. For that which is moved unnaturally also has an unnatural state of rest.

             748. Next where he says, 'Further, some things have . . .' (231 a 10), he gives the second clarification. This is an explanation of what was said about the contrariety of natural and violent motion.

             He says that in some things there is both natural and unnatural motion. For example, fire is moved upward naturally and downward unnaturally. The question is whether the violent downward motion of fire or natural downward motion of earth is contrary to the natural upward motion of fire.

             He answers that both are contrary, but not in the same way. The downward motion of earth is contrary to the upward motion of fire as natural to natural. But the downward motion of fire is contrary to the upward motion of fire as violent to natural. And the same explanation [ratio] applies to the contrariety of states of rest.

             749. Next where he says, 'But there would seem . . .' (231 a 18), he gives the third clarification. This is an explanation of what was said about the contrariety of rest to motion.

             He says that perhaps motion is opposed to rest, not simply, but to a certain degree. For when one is being moved from that in which he was at rest, and when he is abandoning that state, it seems that he still has that which is being abandoned. Hence, if rest here is contrary to motion from here to a contrary, it would follow that the contraries are together. But to some degree it is still at rest while it remains in the terminus from which. And it is universally true of that which is moved that something is in the terminus from which and something is in the terminus to which. Hence, rest is opposed to motion less than the contrary motion is opposed, as was explained above.

             And finally he summarizes for the sake of clarity.

             The very same words which were used above are repeated here. From this it is clear that these are not the words of Aristotle, but of some commentator.