Disputationes metaphysicae

1. The Aristotelian definition.—What the genus in it is.—Aristotle, V Metaph., c. 2, and II Phys., c. 3, defines the efficient cause in general, saying that it is that whence is the first principle of change or of rest. This definition needs much interpretation and addition in order to be brought to its true sense, so that it may comprehend every efficient cause and declare its proper causality. For in the first place there seems to be nothing in it that is set down in place of a genus, for the particle unde (whence), which alone Aristotle sets down, is both improperly put in place of a genus and is very equivocal; for both time and place can be said to be that whence motion begins. Hence it seems that a principle per se must be understood in place of the genus; but lest it seem that a tautology is committed by saying that the efficient cause is a principle per se whence is the first principle of motion, it will have to be said that the efficient cause is a principle per se from which (a quo) change first is or comes to be; and thus it comes about that Aristotle's description virtually contains this genus, through which the efficient cause can be defined.

2. How it may be fitted to the thing defined alone.—But then a second difficulty arises, because the definition so expounded also fits the other causes; for matter, in its own genus, is a principle per se of change and of rest. Nor is it enough if it be said that it is excluded through the particle first; because, although the formal cause can be excluded through that particle (for in truth it is not the first principle of change, but rather its terminus, on account of which we said above that the form is not properly the cause of the generation, but of the thing generated), nevertheless the material cause is not excluded through that particle, because in its own genus it concurs to the change just as firstly as the efficient cause, and therefore it too is a principle per se whence change first begins. Someone will perhaps say that, although with respect to some effecting matter causes the change simultaneously with the efficient, nevertheless, comparing the material and the efficient cause absolutely, the latter is prior, because matter itself must be made before it causes. But this has no bearing on the present question, because that antecedence is remote and with respect to another action, which Aristotle does not mention, nor is it sufficiently established that he knew of it. Hence it is as it were per accidens with respect to the concurrence of matter and the efficient to natural change. That, therefore, is not enough to exclude the causality of matter; otherwise the secondary efficient cause would also be excluded, because it is not first simply with respect to the effecting, since it must itself first be effected. Two things, therefore, can be said. One is that, although in reality natural change is simultaneously from the efficient and the material cause, yet according to notion the influx of the efficient cause is prior to that of the material; whence, speaking according to precise formal notions, the passion is from the action and not conversely, and therefore this causal statement is true and proper: because the agent acts, the matter receives. Conversely, however, it will not properly be said that the agent acts because the matter receives. In this way, therefore, the efficient is said to be first in the notion of causing in comparison with matter. Secondly, it is said that matter is excluded through the particle unde. For in strictness it signifies a relation to an extrinsic principle; for matter is the cause of change because it receives it intrinsically in itself and sustains it in itself; but the agent is the principle of the action or change only because the latter flows from it and bears an essential relation to it, as to the extrinsic principle on which it depends; and this proper notion and relation is declared by the particle unde, which is equivalent to the particle a quo, which is properly attributed to the efficient; for the material principle is rather ex quo. Hence, for the sake of greater clarity, the efficient cause could be said to be an extrinsic principle per se from which change first is.

3. How the end is excluded from it.—But then a third difficulty occurs, because the definition so declared fits the final cause rather than the efficient; for the end is a principle per se and extrinsic, and is prior in causing to the efficient; for the efficient does not act except as moved by the end, and therefore the final cause is commonly said to be the first among all the causes. But since the influx of the final cause is very obscure, especially with respect to physical and real change, it is therefore briefly said that, although in the order of intention the final cause is prior, yet in execution the efficient cause is first; indeed, that it alone is what per se and extrinsically really inflows or moves. And in this way the aforesaid definition is to be understood, which the particle unde or a quo sufficiently declares. For the end is a principle or cause for the sake of which change comes about, or towards which it tends; it is not, however, properly called a principle from which or whence action first flows; but this is said most properly of the efficient cause.

4. Whether that definition fits the first and the second causes.—But at once a fourth difficulty occurs, because that definition does not embrace every efficient cause. For here it seems to fit the first cause alone, because that alone is whence all change first begins; or at most it fits the principal cause, not the instrumental cause or the faculty, which is the proximate principle of acting; for an instrument does not act except as moved, or in the power of a prior agent, and therefore the instrument cannot be said to be that whence motion first is. From another side, that definition seems not to fit the first efficient cause according to its first and chief efficiency, which is through creation, because creation is not a change. To the first part it must be said that the particle whence motion first begins is not to be understood of the first principle simply, that is, of one wholly independent and having no prior cause; otherwise, as the argument concludes, the definition would fit only the first mover or efficient; but it is to be understood of the first principle in such an order or genus of causing. Hence the secondary cause is called the first principle whence motion is, because in the genus of proximate cause motion first arises from it; and thus Aristotle gives the example of the father with respect to the son. Some, however, with Alexander of Aphrodisias, think that instrumental causes are excluded by that particle, because they are not properly causes. But since Aristotle gives the example of the counselling cause, which seems more improper, and concludes universally that the definition fits every efficient or transmuting thing, it seems rather to be said that he comprehended all the modes of efficient causes, as Scotus noted, and that each cause in its own order has the notion of a principle from which action first is, whether as from a principal principle, or as from an instrumental one, or as from a perfecting and executing one, or as from one counselling or assisting. That particle first, therefore, was added only either to exclude causes wholly per accidens, which in no way properly inflow into the action, or to denote the proper mode of causing of the efficient cause and to distinguish it from the material and formal, which are not first in the way the efficient is, as was declared above. To the second part: if we look to Aristotle's mind, he seems indeed to have defined only the natural efficient cause, which always acts through motion or change; for in II Phys. Aristotle was disputing only of natural causes, and yet in V Metaph. he added nothing whatever either to the definition or to the doctrine of the efficient cause. In both places, however, he intimated that, due proportion being kept, the definition can be extended to every efficient cause. Hence, giving examples, he said: As he who counsels, and the father, and in one word that which makes, of what is made, and that which changes, of what is changed. If, therefore, in place of the word mutationis (of change) or quietis (of rest) we put the word actionis (of action), the definition will comprehend every efficient cause, even the first as creating, because, as we shall see below, creation too is an action, although it is not a change.

5. How the thing defined is not included in it.—From this, however, another difficulty arises, because in this way the thing defined seems in a certain manner to be placed in the definition; for the efficient cause, according to the exposition given, will be a principle per se from which action first is; but what action is, is equally obscure; indeed it is almost the same thing and needs the same exposition, for action and effecting are the same; whence the efficient or agent is named from action; therefore to define the efficient through action is to declare the same through the same, or the obscure through the more obscure. Add that a cause is to be defined through its effect, since they are correlatives; but action is not the effect of the efficient cause, but the notion of causing, as I shall say below. It must be said, however, that since action is compared to the agent by way of form, the notion of the agent is not badly declared through its order to action; but Aristotle used the word mutationis (of change), because it is better known to us, so that through it we may understand, in each thing, the emanation or dependence from that principle from which it receives being. Hence, although the proper notion of action and its distinction from the agent and from the effect is more obscure, as we shall see later, yet for the present it is enough to understand by action the emanation and dependence of the effect on its extrinsic cause from which it receives being; for in this way, speaking confusedly and generally, it is most well known that there is in the effect a dependence or emanation from its principle, whatever that dependence or emanation may be.

6. Wherefore, although action is not the effect of the agent, nevertheless, because it is the way to the effect, or the dependence of the effect on the agent, the effect is sufficiently comprehended or indicated in the action itself. For it is the same to say that the efficient cause is the first principle whence action is as to say whence the effect is, by means of action, or that it is the principle from which the effect flows forth or depends through action. In this the difference between this cause and the others is also rightly signified; for matter and form, speaking per se, do not cause by means of action, but through formal and intrinsic union; the end, however, causes only through metaphorical motion, inasmuch as it is the end; but the efficient causes through its own action flowing from it. And in this is also included that this cause does not give to the effect its own proper formal being, but something else emanating from it by means of action; in which this cause differs from the formal and the material, because these cause their effect by giving their own proper entity, and therefore are called intrinsic causes; but the efficient cause is extrinsic, that is, not communicating to the effect its own proper and (so to speak) individual being, but something else really flowing forth and emanating from such a cause by means of action. From these things, therefore, both Aristotle's definition and the thing itself are sufficiently established, namely, what the efficient cause is and in what it is distinguished from the other genera of causes; all of which will be understood more exactly by declaring the single things that concur in and are necessary to this causality.