LESSON 3

The Existence of a First Efficient Cause and of a First

Material Cause

Chapter 2: 994a 11-994b 9

             153. For intermediate things in a series limited by some first and last thing must have as their cause the first member of the series, which they follow; because if we had to say which one of these three is the cause of the others, we would say that it is the first. What is last is not the cause, since what is last is not a cause of anything. Neither is the intermediate the cause, because it is the cause of only one; for it makes no difference whether one or several intermediates exist, or an infinite or finite number. Indeed, in series that are infinite in this way or in the infinite in general, all parts are intermediates to the same degree right down to the present one. Therefore, if there is nothing first in the whole series, nothing in the series is a cause.

             154. Neither is it possible to proceed to infinity in a downward direction, where there is a starting-point in an upward direction, so that water comes from fire, earth from water, and some other class of things always being generated in this way.

             155. Now there are two ways in which one thing comes from (ex) another. I do not mean from in the sense of after, as the Olympian games are said to come from the Isthmian, but either in the way in which a man comes from a boy as a result of a boy changing, or in the way in which air comes from water.

             156. We say, then, that a man comes from a boy in the sense that what has come into being comes from what is coming into being, or in the sense that what has been completed comes from what is being completed. For generation is always midway between being and non-being, and thus whatever is coming into being is midway between what is and what is not. Now a learner is one who is becoming learned, and this is the meaning of the statement that the man of science comes from the learner. But water comes from air in the sense that it comes into being when the latter ceases to be.

             157. This is why changes of the former kind are not reversible, and thus a boy does not come from a man. The reason is that the thing which comes into being does not come from generation but exists after generation. This is the way in which the day comes from the dawn, i.e., in the sense that it exists after the dawn; and this is why the dawn cannot come from the day. On the other hand, changes of the latter sort are reversible.

             158. Now in neither way is it possible to proceed to infinity; for existing intermediaries must have some end, and one thing may be changed into the other because the corruption of one is the generation of the other.

             159. At the same time it is impossible that an eternal first cause should be corrupted; for since generation is not infinite in an upward direction, then a first principle by whose corruption something else is produced could not be eternal.

COMMENTARY

             301. Having assumed above that the causes of beings are not infinite in number, the Philosopher now proves this. First (153:C 301), he proves that there are not an infinite number of causes in a series; and second (170:C 330), that the classes of causes are not infinite in number ("Again, if the classes of causes").

             In regard to the first he does four things. First, he proves his assumption in the case of efficient or moving causes; second (154:C 305), in the case of material causes ("Neither is it possible"); third (160:C 316), in the case of final causes ("Again, that for the sake of which"); and fourth (164:C 320), in the case of formal causes ("Nor can the quiddity").

             In regard to the first he proceeds as follows. First, he lays down this premise: in the case of all those things which lie between two extremes, one of which is last and the other first, the first is necessarily the cause of those which come after it, namely, what is intermediate and what is last.

             302. Then he proves this premise by a process of elimination. For if we had to say which of the three, i.e., the first, the intermediate, or the last, is the cause of the others, we would have to say that the first is the cause. We could not say that what is last is the cause of all the others, because it is not a cause of anything; for in other respects what is last is not a cause, since an effect follows a cause. Nor could we say that the intermediate is the cause of all the others, because it is the cause of only one of them, namely, what is last.

             303. And lest someone should think that an intermediate is followed by only one thing, i.e., what is last (for this occurs only when there is a single thing between two extremes), in order to exclude this interpretation he adds that it makes no difference to the premise given above whether there is only one intermediate or several, because all intermediates are taken together as one insofar as they have in common the character of an intermediate. Nor again does it make any difference whether there are a finite or infinite number of intermediates, because so long as they have the nature of an intermediate they cannot be the first cause of motion. Further, since there must be a first cause of motion prior to every secondary cause of motion, then there must be a first cause prior to every intermediate cause, which is not an intermediate in any sense, as though it had a cause prior to itself. But if we were to hold that there is an infinite series of moving causes in the above way, then all causes would be intermediate ones. Thus we would have to say without qualification that all parts of any infinite thing, whether of a series of causes or of continuous quantities, are intermediate ones; for if there were a part that was not an intermediate one, it would have to be either a first or a last; and both of these are opposed to the nature of the infinite, which excludes every limit, whether it be a starting-point or a terminus.

             304. Now there is another point that must be noted, i.e., that if there are several intermediate parts in any finite thing, not all parts are intermediate to the same degree; for some are closer to what is first, and some to what is last. But in the case of some infinite thing in which there is neither a first nor last part, no part can be closer to or farther away from either what is first or what is last. Therefore all parts are intermediates to the same degree right down to the one you designate now. Consequently, if the causes of motion proceed to infinity in this way, there will be no first cause. But a first cause is the cause of all things. Therefore it will follow that all causes are eliminated; for when a cause is removed the things of which it is the cause are also removed.

             305. Neither is it possible (154).

             He shows that it is impossible to proceed to infinity in the case of material causes. First (154:C 305), he states what he intends to prove. Second (155:C 308), he proceeds with his proof ("Now there are two ways").

             In regard to the first it must be noted that a patient is subjected to the action of an agent. Therefore to pass from agent to agent is to proceed in an upward direction, whereas to pass from patient to patient is to proceed in a downward direction. Now just as action is attributed to the cause of motion, so is undergoing action attributed to matter. Therefore among the causes of motion the process is in an upward direction, whereas among material causes the process is in a downward direction. Consequently, since he showed among moving causes that it is impossible to proceed to infinity, as it were, in an upward direction, he adds that it is impossible to proceed to infinity in a downward direction, i.e., in the process of material causes, granted that there is a starting-point in an upward direction among the causes of motion.

             306. He illustrates this by way of the process of natural bodies, which proceeds in a downward direction, as if we were to say that water comes from fire, earth from water, and so on to infinity. He uses this example in accordance with the opinion of the ancient philosophers of nature, who held that one of these elements is the source of the others in a certain order.

             307. However, this can also be explained in another way, inasmuch as we understand that in the case of moving causes there are evident to the senses certain ultimate effects which do not move anything else. Therefore we do not ask if there is an infinite regress in the lower members of that class, but if there is an infinite regress in the higher ones. But in regard to the class of material causes, he assumes that there is one first cause which is the foundation and basis of the others; and he inquires whether there is an infinite regress in a downward direction in the process of those things which are generated from matter. The example which he gives illustrates this, because he does not say that fire comes from water and this in turn from something else, but the converse, i.e., that water comes from fire, and something else again from this. For this reason first matter is held to exist; and he asks whether the things that are generated from matter proceed to infinity.

             308. Now there are two ways in which (155).

             He proves his original thesis. Concerning this he does four things. First (155:C 308), he distinguishes between the two ways in which one thing comes from something else. Second (156:C 310), he shows that these two ways differ in two respects ("We say, then, that a man"). Third (158:C 312), he shows that it is impossible to proceed to infinity in either of these ways ("Now in neither way"). Fourth (159:C 314), he shows in which of these ways other things come from the first material principle ("At the same time").

             He says, first, that one thing "comes from" another properly and essentially in two ways. He speaks thus in order to exclude that way in which something is said in an improper sense to come from something else only by reason of the fact that it comes after it, as when it is said that certain feasts of the Greeks called the Olympian come from those called the Isthmian, or as if we were to say that the feast of the Epiphany comes from the feast of the Nativity. But this is an improper use of the word, because the process of coming to be is a change, and in a change it is not only necessary that an order exist between the two limits of the change but also that both limits have the same subject. Now this is not the case in the above example, but we speak in this way insofar as we think of time as the subject of different feasts.

             309. Now properly speaking it is necessary to say that one thing comes from something else when some subject is changed from this into that. This occurs in two ways: first, as when we say that a man comes from a boy in the sense that a boy is changed from boyhood to manhood; second, as when we say that air comes from water as a result of substantial change.

             310. We say, then, that a man (156).

             He explains the twofold sense in which these two ways differ. First, we say that a man comes from a boy in the sense that what has already come into being comes from what is coming into being, or in the sense that what has already been completed comes from what is being completed. For anything in a state of becoming and of being completed is midway between being and non-being, just as generation is midway between existence and nonexistence. Therefore, since we reach an extreme through an intermediate, we say that what has been generated comes from what is being generated, and that what has been completed comes from what is being completed. Now this is the sense in which we say that a man comes from a boy, or a man of science from a learner, because a learner is one who is becoming a man of science. But in the other sense, i.e., the one in which we say that water comes from fire, one of the limits of the change is not related to the other as a passage or intermediate, as generation is to being, but rather as the limit from which a thing starts in order to reach another limit. Therefore one comes from the other when the other is corrupted.

             311. This is why changes (157).

             He infers another difference from the foregoing one. For since, in the first way, one thing is related to the other as generation is to being, and as an intermediate to a limit, it is evident that one is naturally ordained to the other. Therefore they are not reversible so that one comes from the other indifferently. Consequently we do not say that a boy comes from a man, but the reverse. The reason for this is that those two things, of which one is said to come from the other in this way, are not related to each other in the same way as the two limits of a change, but as two things one of which comes after the other in sequence. And this is what he means when he says that "what has come into being" (i.e., the terminus of generation or being) does not come from generation as though generation itself were changed into being, but is that which exists after generation, because it follows generation in a natural sequence; just as one's destination comes after a journey, and as what is last comes after what is intermediate. Therefore, if we consider these two things, i.e., generation and being, the way in which they are related does not differ from the one we have excluded, in which sequence alone is considered, as when we say that the day comes from the dawn because it comes after the dawn. Moreover, this natural sequence prevents us from saying in an opposite way that the dawn comes "from the day," i.e., after the day; and for the same reason a boy cannot come from a man. But in the other sense in which one thing comes from another, the process is reversible; for just as water is generated by reason of air being corrupted, in a similar way air is generated by reason of water being corrupted. The reason is that these two are not related to each other in a natural sequence, i.e., as an intermediate to a limit, but as two limits, either one of which can be first or last.

             312. Now in neither way (158).

             He shows that it is impossible to proceed to infinity in either of these ways. First, in the way in which we say that a man comes from a boy; for the thing from which we say something else comes as a man comes from a boy has the position of an intermediary between two limits, i.e., between being and non-being. But an infinite number of intermediates cannot exist when certain limits are held to exist, since limits are opposed to infinity. Therefore, it is impossible to have an infinite series in this way.

             313. In like manner it is impossible to have an infinite series in the other way; for in that way one limit is converted into the other, because the corruption of one is the generation of the other, as has been explained. Now wherever a reversible process exists there is a return to some first thing in the sense that what was at first a starting-point is afterwards a terminus. This cannot occur in the case of things that are infinite, in which there is neither a starting-point nor a terminus. Consequently, there is no way in which one thing can come from another in an infinite regress.

             314. At the same time it is impossible (159).

             He shows in which of these ways something comes from first matter. Now it must be noted that in this place Aristotle uses two common suppositions accepted by all of the ancient philosophers: first, that there is a primary material principle, and therefore that in the process of generation there is no infinite regress on the part of the higher, i.e., of that from which a thing is generated; second, that matter is eternal. Therefore, from this second supposition he immediately concludes that nothing comes from first matter in the second way, i.e., in the way in which water comes from air as a result of the latter's corruption, because what is eternal cannot be corrupted.

             315. But since someone could say that the philosophers did not hold that the first material principle is eternal because it remains numerically one eternally but because it is eternal by succession (as if the human race were held to be eternal), he therefore excludes this from the first supposition. He says that since generation is not infinite in an upward direction but stops at a first material principle, then if there is a first material principle by reason of whose corruption other things come into being, it must not be the eternal principle of which the philosophers speak. The reason is that the first material principle cannot be eternal if other things are generated by reason of its corruption, and it in turn is generated by the corruption of something else. It is evident, then, that a thing comes from this first material principle as something imperfect and potential which is midway between pure nonbeing and actual being, but not as water comes from air by reason of the latter's corruption.