LESSON 2

The Four Classes of Causes. Several Causes of the Same Effect. Causes May Be Causes of Each Other. Contraries Have the Same Cause

Chapter 2: 1013a 24-1013b 16

             405. In one sense the term cause means that from which, as something intrinsic, a thing comes to be, as the bronze of a statue and the silver of a goblet, and the genera of these. In another sense it means the form and pattern of a thing, i.e., the intelligible expression of the quiddity and its genera (for example, the ratio of 2:1 and number in general are the cause of an octave chord) and the parts which are included in the intelligible expression. Again, that from which the first beginning of change or of rest comes is a cause; for example, an adviser is a cause, and a father is the cause of a child, and in general a maker is a cause of the thing made, and a changer a cause of the thing changed. Further, a thing is a cause inasmuch as it is an end, i.e., that for the sake of which something is done; for example, health is the cause of walking. For if we are asked why someone took a walk, we answer, "in order to be healthy"; and in saying this we think we have given the cause. And whatever occurs on the way to the end under the motion of something else is also a cause. For example, reducing, purging, drugs and instruments are causes of health; for all of these exist for the sake of the end, although they differ from each other inasmuch as some are instruments and others are processes. These, then, are nearly all the ways in which causes are spoken of.

             406. And since there are several senses in which causes are spoken of, it turns out that there are many causes of the same thing, and not in an accidental way. For example, both the maker of a statue and the bronze are causes of a statue not in any other respect but insofar as it is a statue. However, they are not causes in the same way, but the one as matter and the other as the source of motion.

             407. And there are things which are causes of each other. Pain, for example, is a cause of health, and health is a cause of pain, although not in the same way, but one as an end and the other as a source of motion.

             408. Further, the same thing is sometimes the cause of contraries; for that which when present is the cause of some particular thing, this when absent we sometimes blame for the contrary. Thus the cause of the loss of a ship is the absence of the pilot whose presence is the cause of the ship's safety. And both of these--the absence and the presence--are moving causes.

COMMENTARY

             763. Here the Philosopher distinguishes the various senses in which the term cause is used; and in regard to this he does two things. First (405:C 763), he enumerates the classes of causes. Second (410:C 783), he gives the modes of causes ("Now the modes").

             In regard to the first part he does two things. First, he enumerates the various classes of causes. Second (409:C 777), he reduces them to four ("All the causes").

             In regard to the first part he does two things. First, he enumerates the different classes of causes. Second (406:C 773), he clarifies certain things about the classes of causes ("And since").

             He accordingly says, first (405), that in one sense the term cause means that from which a thing comes to be and is "something intrinsic," i.e., something which exists within the thing. This is said to distinguish it from a privation and also from a contrary; for a thing is said to come from a privation or from a contrary as from something which is not intrinsic; for example, white is said to come from black or from not-white. But a statue comes from bronze and a goblet from silver as from something which is intrinsic; for the nature bronze is not destroyed when a statue comes into being, nor is the nature silver destroyed when a goblet comes into being. Therefore the bronze of a statue and the silver of a goblet are causes in the sense of matter. He adds "and the genera of these," because if matter is the species of anything it is also its genus. For example, if the matter of a statue is bronze, its matter will also be metal, compound and body. The same holds true of other things.

             764. In another sense cause means the form and pattern of a thing, i.e., its exemplar. This is the formal cause, which is related to a thing in two ways. In one way it stands as the intrinsic form of a thing, and in this respect it is called the formal principle of a thing. In another way it stands as something which is extrinsic to a thing but is that in likeness to which it is made, and in this respect an exemplar is also called a thing's form. It is in this sense that Plato held the Ideas to be forms. Moreover, because it is from its form that each thing derives its nature, whether of its genus or of its species, and the nature of its genus or of its species is what is signified by the definition, which expresses its quiddity, the form of a thing is therefore the intelligible expression of its quiddity, i.e., the formula by which its quiddity is known. For even though certain material parts are given in the definition, still it is from a thing's form that the principal part of the definition comes. The reason why the form is a cause, then, is that it completes the intelligible expression of a thing's quiddity. And just as the genus of a particular matter is also matter, in a similar way the genera of forms are the forms of things; for example, the form of the octave chord is the ratio of 2:1. For when two notes stand to each other in the ratio of 2:1, the interval between them is one octave. Hence twoness is its form; for the ratio of 2:1 derives its meaning from twoness. And because number is the genus of twoness, we may therefore say in a general way that number is also the form of the octave, inasmuch as we may say that the octave chord involves the ratio of one number to another. And not only is the whole definition related to the thing defined as its form, but so also are the parts of the definition, i.e., those which are given directly in the definition. For just as two-footed animal capable of walking is the form of man, so also are animal, capable of walking and two-footed. But sometimes matter is given indirectly in the definition, as when the soul is said to be the actuality of a physical organic body having life potentially.

             765. In a third sense cause means that from which the first beginning of change or of rest comes, i.e., a moving or efficient cause. He says "of change or of rest," because motion and rest which are natural are traced back to the same cause, and the same is true of motion and of rest which are a result of force. For that cause by which something is moved to a place is the same as that by which it is made to rest there. "An adviser" is an example of this kind of cause, for it is as a result of an adviser that motion begins in the one who acts upon his advice for the sake of safeguarding something. And in a similar way "a father is the cause of a child." In these two examples Aristotle touches upon the two principles of motion from which all things come to be, namely, purpose in the case of an adviser, and nature in the case of a father. And in general every maker is a cause of the thing made and every changer a cause of the thing changed.

             766. Moreover, it should be noted that according to Avicenna there are four modes of efficient cause, namely, perfective, dispositive, auxiliary and advisory.

             An efficient cause is said to be perfective inasmuch as it causes the final perfection of a thing, as the one who induces a substantial form in natural things or artificial forms in things made by art, as a builder induces the form of a house.

             767. An efficient cause is said to be dispositive if it does not induce the final form that perfects a thing but only prepares the matter for that form, as one who hews timbers and stones is said to build a house. This cause is not properly said to be the efficient cause of a house, because what he produces is only potentially a house. But he will be more properly an efficient cause if he induces the ultimate disposition on which the form necessarily follows; for example, man generates man without causing his intellect, which comes from an extrinsic cause.

             768. And an efficient cause is said to be auxiliary insofar as it contributes to the principal effect. Yet it differs from the principal efficient cause in that the principal efficient cause acts for its own end, whereas an auxiliary cause acts for an end which is not its own. For example, one who assists a king in war acts for the king's end. And this is the way in which a secondary cause is disposed for a primary cause. For in the case of all efficient causes which are directly subordinated to each other, a secondary cause acts because of the end of a primary cause; for example, the military art acts because of the end of the political art.

             769. And an advisory cause differs from a principal efficient cause inasmuch as it specifies the end and form of the activity. This is the way in which the first agent acting by intellect is related to every secondary agent, whether it be natural or intellectual. For in every case a first intellectual agent gives to a secondary agent its end and its form of activity; for example, the naval architect gives these to the shipwright, and the first intelligence does the same thing for everything in the natural world.

             770. Further, to this genus of cause is reduced everything that makes anything to be in any manner whatsoever, not only as regards substantial being, but also as regards accidental being, which occurs in every kind of motion. Hence he says not only that the maker is the cause of the thing made, but also that the changer is the cause of the thing changed.

             771. In a fourth sense cause means a thing's end, i.e., that for the sake of which something is done, as health is the cause of walking. And since it is less evident that the end is a cause in view of the fact that it comes into being last of all (which is also the reason why this cause was overlooked by the earlier philosophers, as was pointed out in Book I [84:C 177]), he therefore gives a special proof that an end is a cause. For to ask why or for what reason is to ask about a cause, because when we are asked why or for what reason someone walks, we reply properly by answering that he does so in order to be healthy. And when we answer in this way we think that we are stating the cause. Hence it is evident that the end is a cause. Moreover, not only the ultimate reason for which an agent acts is said to be an end with respect to those things which precede it, but everything that is intermediate between the first agent and the ultimate end is also said to be an end with respect to the preceding agents. And similarly those things are said to be causes from which motion arises in subsequent things. For example, between the art of medicine, which is the first efficient cause in this order, and health, which is the ultimate end, there are these intermediates: reducing, which is the most proximate cause of health in those who have a superfluity of humors; purging, by means of which reducing is brought about; "drugs," i.e., laxative medicine, by means of which purging is accomplished; and "instruments," i.e., the instruments by which medicine or drugs are prepared and administered. And all such things exist for the sake of the end, although one of them is the end of another. For reducing is the end of purging, and purging is the end of purgatives. However, these intermediates differ from each other in that some are instruments, i.e., the instruments by means of which medicine is prepared and administered (and the administered medicine itself is something which nature employs as an instrument); and some--purging and reducing--are processes, i.e., operations or activities.

             772. He concludes, then, that "these are the ways in which causes are spoken of (405)," i.e., the four ways; and he adds "nearly all" because of the modes of causes which he gives below. Or he also adds this because the same classes of causes are not found for the same reason in all things.

             773. And since (406).

             Then he indicates certain points which follow from the things said above about the causes, and there are four of these. The first is that, since the term cause is used in many senses, there may be several causes of one thing not accidentally but properly. For the fact that there are many causes of one thing accidentally presents no difficulty, because many things may be accidents of something that is the proper cause of some effect, and all of these can be said to be accidental causes of that effect. But that there are several proper causes of one thing becomes evident from the fact that causes are spoken of in various ways. For the maker of a statue is a proper cause and not an accidental cause of a statue, and so also is the bronze, but not in the same way. For it is impossible that there should be many proper causes of the same thing within the same genus and in the same order, although there can be many causes providing that one is proximate and another remote; or that neither of them is of itself a sufficient cause, but both together. An example would be many men rowing a boat. Now in the case in point these two things are causes of a statue in different ways: the bronze as matter, and the artist as efficient cause.

             774. And there are (407).

             Then he sets down the second fact that may be drawn from the foregoing discussion. He says that it may also happen that any two things may be the cause of each other, although this is impossible in the same class of cause. But it is evident that this may happen when causes are spoken of in different senses. For example, the pain resulting from a wound is a cause of health as an efficient cause or source of motion, whereas health is the cause of pain as an end. For it is impossible that a thing should be both a cause and something caused. Another text states this better, saying that "exercise is the cause of physical fitness," i.e., of the good disposition caused by moderate exercise, which promotes digestion and uses up superfluous humors.

             775. Now it must be borne in mind that, although four causes are given above, two of these are related to one another, and so also are the other two. The efficient cause is related to the final cause, and the material cause is related to the formal cause. The efficient cause is related to the final cause because the efficient cause is the starting point of motion and the final cause is its terminus. There is a similar relationship between matter and form. For form gives being, and matter receives it. Hence the efficient cause is the cause of the final cause, and the final cause is the cause of the efficient cause. The efficient cause is the cause of the final cause inasmuch as it makes the final cause be, because by causing motion the efficient cause brings about the final cause. But the final cause is the cause of the efficient cause, not in the sense that it makes it be, but inasmuch as it is the reason for the causality of the efficient cause. For an efficient cause is a cause inasmuch as it acts, and it acts only because of the final cause. Hence the efficient cause derives its causality from the final cause. And form and matter are mutual causes of being: form is a cause of matter inasmuch as it gives actual being to matter, and matter is a cause of form inasmuch as it supports form in being. And I say that both of these together are causes of being either in an unqualified sense or with some qualification. For substantial form gives being absolutely to matter, whereas accidental form, inasmuch as it is a form, gives being in a qualified sense. And matter sometimes does not support a form in being in an unqualified sense but according as it is the form of this particular thing and has being in this particular thing. This is what happens in the case of the human body in relation to the rational soul.

             776. Further, the same thing (408).

             Then he gives the third conclusion that may be drawn from the foregoing discussion. He says that the same thing can be the cause of contraries. This would also seem to be difficult or impossible if it were related to both in the same way. But it is the cause of each in a different way. For that which when present is the cause of some particular thing, this when absent "we blame," i.e., we hold it responsible, "for the contrary." For example, it is evident that by his presence the pilot is the cause of a ship's safety, and we say that his absence is the cause of the ship's loss. And lest someone might think that this is to be attributed to different classes of causes, just as the preceding two were, he therefore adds that both of these may be reduced to the same class of cause--the moving cause. For the opposite of a cause is the cause of an opposite effect in the same line of causality as that in which the original cause was the cause of its effect.