Disputationes metaphysicae

1. If the very name of efficient cause is attentively considered, it does not seem to signify a cause which takes away being, but which gives being; and therefore in all that we have said so far about this cause we have explained only the causality of this cause inasmuch as it gives or inflows being; because, however, philosophers commonly speak of the efficient cause in such a way that they think it effects not only the generations of things but also their corruptions—which is not to give being but rather to take it away—therefore, for the completion of this disputation, it is necessary that we say a few things about this matter too, and explain whether this too is true efficiency, and by what causality and power it takes place.

2. Various modes of destroying a thing.—It must be noted, then, that a thing can be corrupted or cease to be in two ways: first, because the non-being of one thing follows from the being of another. Secondly, because a thing is absolutely deprived of its being as it were immediately and without consecution from another being. In the first way wood is corrupted when fire is generated from it, because the being of wood cannot be together in the same thing with the being of fire. In the latter way, however, light in the air is corrupted by the absence of the sun; for no being is introduced into the air repugnant to the being of the luminous, but that form simply perishes, the conserving cause withdrawing. Although the very being of the sun in the other hemisphere can also be said to be naturally incompossible with the being of light in the air of this hemisphere; but that is very remotely, extrinsically and per accidens, on account of the defect of a condition necessary for acting, and not on account of a repugnance which is intrinsically and per se between light and Ubi.

Resolution of the question

3. By positive action nothing is ever directly destroyed.—This being supposed, two principles seem certain: the first is that the corruption and ceasing of a thing never takes place through positive and proper efficiency, except inasmuch as the lack of some being follows upon the effecting or positing of another being. It is proved, because positive efficiency takes place only through positive action; but positive action does not immediately and per se tend to non-being; therefore through it the corruption or destruction of something cannot be positively effected, except inasmuch as through it is made the being of some thing with which the non-being of another is necessarily conjoined. The major was proved in the preceding section, and the same is established from the terms themselves; for efficiency and action are the same, as are efficient and agent. The minor is proved, both because real or positive action (for they are the same) necessarily tends to a real terminus, as will be shown below in its place, and in transient actions it is denied by no one; but a real terminus receives some real being through the action; for this is why it is its terminus. Hence even those who deny a real terminus in immanent actions cannot deny that the action itself, inasmuch as it is positively made, receives some real being from its efficient cause. But if through that action something is immediately corrupted (that is, without the production of another terminus or thing), it is only inasmuch as the being of that action, whatever it may be, is incompossible with the other being which is destroyed. It is, then, universally true that through positive efficiency nothing is immediately destroyed, but only consequently upon another being which is made through the action; which consecution is always founded on some repugnance of such things. And it is confirmed from that common axiom that no agent operates intending evil; but non-being as such has the notion of evil; positive efficiency, therefore, never per se tends to non-being, but to some being from which another's non-being follows.

4. An objection is dissolved.—You will say: although this is true in natural agents, it is not so in voluntary ones; for God can will something not to be, not in order that another may be, but only in order that it may not be; and one man often in this way intends the death of another; hence in artificial things action often per se primo tends to destruction. It is answered that, although a voluntary agent can per se intend the destruction of a thing, it cannot execute and effect it through an action which of itself primarily tends to non-being, for the reason touched upon above. Hence God Himself too, when He wills to destroy some thing, will either obtain this through the mere suspension of His influx without positive action, or, if He wills to use positive action, He will necessarily make something from which such corruption follows. But man, who cannot destroy a thing through the mere suspension of influx, because things do not depend on him in their being, always uses actions which commonly are nothing but the local changes of bodies, which directly and per se tend to their proper termini; and from them per accidens follows corruption or destruction, which, although it is intended per se as to the extrinsic intention of the agent, yet takes place per accidens or consequently through such action.

5. The destruction of a thing directly intended takes place through lack of efficiency.—The Aristotelian axiom is explained.—The second principle is: when the ceasing of some thing does not follow upon the positive effecting of another, but takes place by itself alone, it does not take place through proper efficiency, but through lack of efficiency. This principle follows from the preceding, because positive action is only towards some positive being; therefore, while no being is communicated, positive action cannot intervene; but in this kind of ceasing and corruption no being is communicated, but is only taken away; therefore it cannot take place through true action; therefore it must necessarily take place through lack of action, because no other mode of causality can intervene which pertains to the efficient cause. You will say that this kind of cause seems to be only per accidens, such as that which removes the cause per se; but a cause of corruption of this kind is not only per accidens, but per se; therefore it is not only through the absence of the cause, but through proper efficiency. The minor is evident, both from Aristotle saying that, just as the presence of the sailor is the cause of the conservation of the ship, so his absence is the cause of its sinking; and also because that effect cannot be referred back to a more proper and per se cause. And on this seems to be founded that common axiom: If affirmation is the cause of affirmation, negation will be the cause of negation, which is most known in proper, per se and adequate causes. It is answered that from this very axiom it is gathered that the per se cause of corruption (if indeed it can have any) is not to be sought positively acting, but rather not acting, since the cause must be proportioned to the effect. Hence in that example of Aristotle too the absence of the sailor is not an acting cause, but rather a non-acting one. Wherefore, if it is compared to the sinking of the ship inasmuch as this is a certain positive effect, it is only its cause per accidens, considering the thing truly and physically, although morally and imputatively it is reckoned per se, if he was bound to be present; but if it is compared only to the lack of help or defence of the ship, the one negation can be called the per se cause of the other negation; for they have between them proportion and intrinsic and immediate consecution. In this way, then, if a cause per se inflowed being and takes away the influx, it will be called the per se cause of the ceasing of such being, not because by positive action it effects the ceasing, but because in a proportioned mode it is the proper principle and origin of such ceasing. Hence, just as privation is said to exist not through positive being but through lack of being, so it is said to be made not through positive action but through lack of action. And in the same proportion its efficient cause per se is not called such because it positively effects it, but because it takes away the influx by which it per se caused that being which is destroyed by such corruption. Indeed, every cause which by positively effecting destroys another, as such, or inasmuch as it is efficient, is not a cause per se, but per accidens, of the destruction of the other.

Corollaries of the foregoing doctrine

6. In every destruction of a thing change is found, not in every action.—From these principles we can infer some things worthy of note concerning the changes or corruptions of things. For it follows, first, that in every corruption or loss of some real being there intervenes some change, but not always necessarily some action. It is evident from the second principle laid down, the definition of change being added. For, on the testimony of Aristotle, a thing is changed when it is otherwise than before; when, therefore, the air from illuminated becomes dark, it is changed; there takes place in it, therefore, some change; and yet that does not take place through action, as is established from the second principle laid down; there is, therefore, change there without action, and the same holds in all similar cases. The reason, however, is that that change is purely privative, not positive. Whence it comes about that this happens only in accidental changes, if we speak properly and according to the common course of nature about change, because the subject of an accident can sometimes lose it even if it does not acquire another; but the subject of a substantial form cannot be substantially changed by losing one form without acquiring another. And therefore I said speaking properly and according to the common course of nature about change. For God could suspend the influx of the substantial form while conserving the matter; or, if the name of change is extended to annihilation, He could wholly change a thing from being to non-being without any action. In which there is also to be noted the difference between free and natural causes, that free causes can suspend their influx from intrinsic dominion and power without any prior action or change in themselves or in another; and so they can also cause this privative change, either in themselves, if they themselves are changeable, as created causes, or in others, as God; but naturally acting causes cannot suspend their influx unless something else is first changed which was necessary for acting; and therefore, although sometimes they change some subject in the aforesaid way without action about it, yet some other action always intervenes, either about the same subject or about another; as the sun does not destroy light in the air by withdrawal of influx unless there precedes an action by which either the sun itself is moved, or the window is closed, etc.

7. Action tending secondarily to destruction is always dependent on a subject.—Annihilation cannot be from a subject.—It follows, secondly, from what has been said, that whenever the corruption or ceasing of a thing takes place through positive action which of itself has consequently to cause such corruption, it is necessary that such action take place from a presupposed subject. The reason is that corruption or ceasing does not take place by virtue of physical action (for so we are speaking), except because that being which is made through such action has natural repugnance with the being which is destroyed; but this natural repugnance can only be in order to the same common subject, which remains under both termini, because between things subsisting per se and having no order to a subject there cannot be natural repugnance on account of which they could not exist together in the nature of things; therefore it is necessary that such action be from something presupposed. And hence it is that proper annihilation cannot be done by God through positive action, because annihilation leaves nothing of the thing which could be the subject of the action. Likewise, because either the action takes place in a subject, and so does not destroy it, and consequently does not effect annihilation, or it takes place without a subject, and so nothing can be made through it which is repugnant to the whole being of another thing; nothing, therefore, can be annihilated through such action. But if someone objects that the action by which the rational soul is made is not from a subject, and yet upon it follows the corruption of another, namely of the embryo, it is answered by denying the minor; but properly that corruption follows either from the action by which the matter is sufficiently disposed for the introduction of the rational soul, or from the action by which the soul itself is united to the body, or from both in their genus, as will be explained below; but each of these actions is from a presupposed subject; creation, however, is only in the order of nature presupposed to the unitive action, but naturally consequent upon the dispositive action. Someone could more difficultly press about that action by which bread is converted into the body of Christ, which is not an action from a presupposed subject, and yet by virtue of it the substance of bread ceases to be. But this difficulty is higher than can be treated in this place; and therefore, to exclude it, I said that the discourse is of natural action and ceasing; but that mystery is wholly supernatural. In it, nevertheless, I think it true either that the ceasing of the bread does not follow there by virtue of physical action alone¹ and the natural connection of things, or, if some such action intervenes there, that it is concerned in some way with a subject, and that the quantity of the bread, conserved without the substance, takes the place of such a subject, as I have disputed more at length in the proper place.

8. The third inference.—Thirdly, I infer that whenever corruption or ceasing takes place through positive action, there intervenes there one simple action, but two partial changes, one positive, the other privative. For a thing happens to be changed in three ways, as Aristotle proposes in V Phys. First, from some form into its lack; and then change takes place, but no action intervenes, speaking per se, as has been said, but lack of conservative action. Secondly, change takes place from pure privation into form, as from dark into bright; then, just as one action intervenes, so also one simple positive change. Thirdly, it happens that a thing is changed from one form into another, as when from hot it becomes cold, and from wood fire. And then one simple action intervenes by which is educed or united the form which is newly introduced into such a subject; for to expel the other no other action is necessary, as we have said; but the change is twofold; for that subject is otherwise by a twofold title, namely, both by lacking the form which it previously had and by having that which it previously did not have. Which two changes are so distinct that in reality they are sometimes separated, as was declared in the first two members. Likewise, one is generation, the other substantial or accidental corruption, or sometimes one is intensification and the other remission. Finally, one is positive, the other privative. Hence, as much as the information of one form and the privation of another differ from each other, so much do those changes differ from each other. Those changes, however, can be called partial because in a physical way they compose one integral transit from one positive terminus into another, which in philosophy is called the conversion of one thing into another. You will say: just as there intervenes there positive and privative change, so there intervenes positive action and the lack of the action by which the opposite form was conserved, either by natural causes or at least by God; for one of these is always necessary; therefore the reason is the same of action and of change. It is answered that the only difference is that the notion of change is saved in a new privation inasmuch as it is in becoming, but the notion of action by no means, but it requires positive influx; which is established from their definitions and essential notions.

9. It is inferred, fourthly, that corruption which takes place through some efficiency takes place through the same principles, whether principal or instrumental, and with the same conditions, as the generation or production upon which such corruption follows. It is proved from what has been said, because there is no other efficiency nor other action towards corruption than towards production; therefore through the same principles by which one being is made another is taken away. Nor can any principle positively concur to taking away being except inasmuch as it concurs to giving another being. From which we said above, against some moderns, that the form introduced into the patient by the agent does not concur effectively to expelling the opposite form—as heat to expelling coldness, and so of the rest—because the form introduced into the patient is not the efficient principle of its own generation; therefore neither of the corruption of the opposite form. Likewise, because, if that efficiency is positive, something positive is made through it; but the form introduced into the patient positively effects nothing by which it expels the other form, but the expulsion of the other form immediately follows; therefore.

10. How one body drives another from its place.—Hence the example commonly adduced of one body expelling another from the same place, which seems to expel it effectively, is not similar; for although Scotus, In IV, dist. 12, q. 3, seems to deny this too, yet in truth the case is not similar. For the two bodies touch each other and one drives the other; and that which is expelled does not lose its place by mere ceasing, but by real change and tendency to another place, to which it is effectively moved by the expelling body; and therefore there intervenes there not only the formal incompossibility of those bodies in the same space, but also a special positive action by which the body, driven from one place, is transferred into another, which is distinct from that by which the other body is introduced into the place of the other. But it is otherwise when a form introduced into one subject expels another, for that which is expelled is not changed positively, but merely privatively ceases to be; and therefore no special efficiency can intervene there. There is, therefore, only formal expulsion there; and universally any cause in its genus so concurs to the non-being of one terminus as it concurs to the being of the other; since, therefore, heat introduced into a subject does not heat it actively but only formally, therefore it does not expel cold actively but only formally. But it is otherwise of the heat which is in the generator; for that is the efficient principle of another heat, and consequently expels the opposite cold. And in the same proportion the heat produced in wood (and the same holds of every similar disposition), although it excludes the directly opposite accidental form only formally, yet corrupts the substance itself dispositively, because in this way it causes the introduction of the opposite form; and, as has been said, in that genus of cause one form concurs to the non-being of the one terminus in which it concurs to the being of the opposite terminus. Hence, because an accident from its proper notion and power has to dispose to the substantial form connatural to it and formally to expel the contrary disposition, it can therefore be said in this genus to corrupt the substance by its own power. But if those accidents and dispositions of the patient also concur effectively to the eduction of their form, by the same genus of efficiency they concur to the corruption of the other; or if they have no efficiency towards the former, neither towards the latter. And so it is universally true that only those are the efficient principles of corruption which effect generation, when corruption takes place through efficiency; for when it happens through mere lack of efficiency, it does not need a proper principle of acting, but it is only necessary that that which was the principle of acting or of conserving the thing cease from acting.