Lecture 5 — Whether action and passion are the same motion

This view has a rational defect. Perhaps it is necessary that the act of the agent and that of the patient should not be the same. The one is “agency” and the other “patiency,” and the outcome and completion of the one is an “action,” while that of the other is a “passion.”

Since, then, they are both motions, we may ask in what they are, if they are different? Either both are in what is acted on and moved, or the agency is in the agent and the patiency in the patient. (If we ought to also call the latter “agency,” the word would be used in two senses.)

Now, if the latter is so, the motion will be in the mover, for the same statement will hold of the mover and the moved. Hence, either every mover will be moved or, though having motion, it will not be moved.

If, on the other hand, both are in what is moved and acted on—both the agency and the patiency (for instance, both teaching and learning, though they are two, in the learner)—then, first, the act of each will not be present in each, and a second absurdity is that a thing will have two motions at the same time.

How will there be two alterations of quality in one subject toward one definite quality? The thing is impossible.

But will the act be one? Someone will say it is contrary to reason to suppose that there should be one identical act of two things that are different in kind.

Yet there will be, if teaching and learning are the same, and agency and patiency. To teach will be the same as to learn, and to act the same as to be acted on—the teacher will necessarily be learning everything that he teaches, and the agent will be acted on.

One may reply that it is not absurd that the act of one thing should be in another. Teaching is the activity of a person who can teach, yet the operation is performed on some patient—it is not cut adrift from a subject, but is of this on that.

There is nothing to prevent two things having one and the same act, provided the acts are not described in the same way, but are related as what can act to what is acting.

Nor is it necessary that the teacher should learn, even if to act and to be acted on are one and the same, provided they are not the same in definition (like “raiment” and “dress”), but are the same merely in the sense in which the road from Thebes to Athens and the road from Athens to Thebes are the same, as has been explained above. For it is not things that are in a way the same that have all their attributes the same, but only such as have the same definition.

But, indeed, it by no means follows from the fact that teaching is the same as learning that to learn is the same as to teach,

any more than it follows from the fact that there is one distance between two things that are at a distance from each other, that the two vectors AB and BA are one and the same.

To generalize: teaching is not the same as learning, or action as passion, in the full sense, though they belong to the same subject, the motion; for the “act of this in that” and the “act of this through the action of that” differ in definition.

What motion is, then, has been stated both generally and particularly. It is not difficult to see how each of its types will be defined—alteration is the act of the alterable qua alterable (or, more scientifically, an act of the potency of that which is active and of that which is passive, as such)—generally and again in each particular case, such as building, healing, and the like. A similar definition will apply to each of the other kinds of motion.

308. After showing that motion is the act both of the mobile and of the mover, the Philosopher now raises a difficulty on this point.

First, he raises the difficulty;

second, he solves it, at one may reply (202b5; [314]).

Regarding the first, he does two things:

first, he prefaces certain things to the difficulty;

second, he pursues the difficulty, at since, then, they are both (202a25; [310]).

309. He therefore says (202a21) that what has been said above now causes a rational—that is, logical—defect, or doubt, by virtue of there being tenable reasons for both sides. In introducing the difficulty, he says that there is an act in that which is active and there is an act in that which is passive, just as above, there was stated to be an act of the mover and of the moved. (Lect. 4, n. 305.) As a matter of fact, the act of the active is called action and the act of the passive is called passion. This he proves by saying that the work and end of anything is its act and perfection; hence, since the work and end of the agent is action and that of the patient is passion, it follows that action is the act of the agent and passion that of the patient.

310. Then, at since, then, they are both (202a25) he pursues this doubt. For it is clear that both action and passion are motion, for each is the same as motion. Therefore, action and passion are either the same motion or diverse motions. If they are diverse, then each of them must be in some subject. Either both will be in the patient, the thing moved, or one of them is in the agent and the other is in the patient.

To say the opposite—namely, that what is in the agent is passion and what is in the patient is action—is to speak equivocally, for it would be calling passion action and vice versa.

The fourth possibility—namely, that both are in the agent—is left out, but this is because it has already been shown (Lect. 4, nn. 302–3.) that motion is in the mobile, which excludes the fourth possibility, that neither be in the patient, but both in the agent.

311. Of the two possibilities listed, he develops the second one first, at now, if the latter is so (202a28). For if anyone says that action is in the agent and passion in the patient, then, since action is a certain motion, as was stated, it follows that motion is in the mover. For the same thing should be true both of the mover and of the moved: if motion is in either one, it is being moved. Or else what is true of the mover and of the moved is also true of the patient and of the agent. Now, if motion is in something, that thing is being moved; therefore, it follows either that every mover is being moved or that something has motion but is not being moved. Each of these seems unreasonable.

312. Then, at if, on the other hand (202a31), he develops the other possibility given above. He says that, if anyone should say that both of them—namely, action and passion—since they are two motions, are in the patient (which is equivalent to saying that teaching, which is on the part of the teacher, and learning, which is on the part of the learner, are both in the learner), then two conflicts arise.

The first is that, if what we said previously is true—namely, that action is an act of the agent—then, if action is not in the agent but in the patient, it will follow that the proper act of each thing is not in the thing of which it is the act.

Then another conflict follows: one and the same thing is being moved according to two motions. For action and passion are now supposed to be two motions. Now, in whatever thing there is a motion, that thing is being moved according to that motion. So, if action and passion are in the mobile, it follows that the mobile is being moved according to two motions. This would be tantamount to having two alterations in one subject, both of them specifically the same, such as one subject being moved to two whitenings, which is impossible. This does not mean that one subject could not be moved by two alterations tending toward two specifically different terms, such as whitening and heating. Nevertheless, it is clear that action and passion terminate at the same specific term; for what the agent does and what the patient receives are one and the same.

313. Then, at but will the act be one (202a36), he develops the other possibility. For it could be said that action and passion are not two motions, but one.

But this leads to four difficulties.

The first is that the acts of things of different species would be the same. For it has been already pointed out that action is an act of the agent and passion an act of the patient, and that these are specifically diverse; but, if action and passion are the same motion, then the acts of specifically different things will be the same.

The second difficulty is that, if action and passion are one motion, then action is the same as passion, such that teaching, which is in the teacher, is the same as learning, which is in the learner.

The third difficulty is that acting would be the same as being acted upon, and teaching would be the same as learning.

The fourth difficulty that follows from this is that every teacher would be learning and every agent would be being acted upon.

314. Then, at one may reply (202b5), he solves the difficulty. From what was settled previously, (Lect. 4, nn. 304, 306.) it is clear that action and passion are not two motions, but one and the same motion; for insofar as motion is from the agent, it is called action, and insofar as it is in the patient, it is called passion.

315. Hence, not all the conflicts that follow from the first case, in which it was supposed that action and passion are two motions, have to be solved. But one remains to be solved even on the supposition that action and passion are one motion: since action is an act of the agent, then, if action and passion are one motion, it follows that the act of the agent is somehow in the patient. Thus, the act of one thing will be in something else.

This remaining difficulty, together with the four listed above, leaves five to be solved.

316. He says in the first place that there is nothing wrong with an act of one thing being in something else, for teaching is an act of the teacher, an act continuously tending from him into someone else without interruption; hence, this act that is the agent’s as being from this is the very one that is in the patient as received in him. But it would be wrong if the act of the one were the act of the other in precisely the same way.

317. Then, at there is nothing to prevent (202b8), he solves another difficulty: two things would have the same act.

And he says that there is nothing to prevent one act belonging to two things, so long as it is not one and the same in thought, but only in reality, as was already explained above, (Lect. 4, n. 307.) when it was pointed out that the distance from one to two and from two to one are the same, and of that which is in potency looking toward the agent and conversely.

For in these cases, the same one reality is assigned to two things according to different accounts: it is assigned to the agent inasmuch as it is from it and to the patient inasmuch as it is in it.

318. The three remaining difficulties, of which one followed logically from the other, he takes care of in reverse order.

He disposes first of the last difficulty introduced, because it is so evidently improper.

Thus, he settles the fifth difficulty third. He says that it is not necessary to say that one who is teaching is learning or that an agent is being acted upon just because to act and to be acted upon are the same, as long as we understand that they are not the same in the way that dress and clothing are the same (for these are the same in account), but in the way that the road from Thebes to Athens and that from Athens to Thebes are the same, being the same as to subject but differing as to account, as said above. (Cf. n. 318; lect. 4, n. 307.)

For it is not necessary that things that are somehow the same should be the same in all ways; that is true only of things that are the same in subject or reality and also in account. And, therefore, even granting that to act and to be acted upon are the same, yet, since they are not the same in account, it will not follow that it is the same for an object to act and to be acted upon.

319. Then, at but, indeed (202b16), he answers the fourth difficulty. And he says that, even though teaching and the learning of the learner were the same, it does not follow that to teach and to learn are the same, since teaching and learning are abstract terms but to teach and to learn are concrete.

Hence, they are being applied to ends or to terms that serve as the basis for the difference in account between action and passion. For just as the distance between two points is one and the same space in the abstract, yet it is not one and the same if we apply it to two concrete places, as when we say that there is a distance between here and there and between there and here.

320. Then, at to generalize (202b19), he answers the third difficulty by destroying the inference that, if action and passion are one motion, they are the same. And he says that ultimately it must be said that it does not follow that action and passion are the same, nor that teaching and learning are, but rather that both are in the same motion. This motion, as a matter of fact, is action from one viewpoint and passion from another. For it is one thing as to account to be an act of a thing as being in that and another to be the act of a thing as being from that.

Now, motion is called action inasmuch as it is an act of the agent as from the agent; it is called passion inasmuch as it is an act of the patient as in the patient. Thus, it is clear that, although the motion of the mover and that of the moved are the same thing due to the fact that motion as such abstracts from these accounts, yet action and passion differ due to the fact that these accounts are included in their signification. From this, it is also apparent that, since motion abstracts from the account of action and passion, it belongs neither in the predicament “action” nor in the predicament “passion,” as some supposed.

321. But two difficulties still remain with respect to this.

The first is this: if action and passion are one motion, and they differ merely in thought, as said above, it seems that they should not be listed as two distinct predicaments, since the predicaments are genera of things.

Second, if motion is either action or passion, motion will not be found in substance, quality, quantity, and place, as said above, (Lect. 2, n. 286.) but only in action and passion.

322. To settle this matter, it should be known that being is divided into the ten predicaments not univocally, as a genus into species, but according to the different modes of existing. Now, the modes of existing are proportional to the modes of predicating. For in predicating something of something else, we say, “this is that”; hence, the ten genera of being are called the ten predicaments.

Now, every predication takes place in one of three ways.

One way is to predicate of a subject that which pertains to its essence, as when I say, “Socrates is man” or “man is animal.” According to this, the predicament of substance is taken.

Another way is to predicate of a subject something that is not of its essence but yet inheres in the subject. This inherent thing may be traceable to the matter in the subject, in which case one has the predicament of “quantity” (for quantity is properly a result of matter; for which reason Plato traced the “large” to matter);

or it is traceable to the form, and in this case, there is the predicament of “quality” (for which reason qualities are founded on quantity, as color in a surface, and figure in lines or in a plane);

or the predication may be due to a relation existing between subject and something else, and thus we have the predicament of “relation” (for when I say, “the man is a father,” it is not something absolute that is predicated of the man, but a relation in him to something without).

The third mode of predicating is when something outside the subject is predicated after the manner of denomination. This allows even extrinsic accidents to be predicated of substance, but yet we do not say that man is whiteness, but that man is white. To be denominated by something extrinsic can occur, generally speaking, to all things in one way or another, and in a special way in those matters that refer only to man.

Speaking generally, a thing can be denominated by something extrinsic either according to the account of cause or according to that of measure. For something is denominated “caused” or “measured” on account of its relationship to something extrinsic.

Now, there are four genera of causes, two of which are parts of the essence, namely, matter and form. Hence, any predication based on these two pertains to the predicament of “substance,” as when I say that man is rational and that man is corporeal.

In regard to the other two causes, the final cause does not cause separately from the agent, for the end is a cause only insofar as it influences the agent. Therefore, the only cause according to which a thing can be denominated something as based on something extrinsic is the agent cause.

Consequently, when something is denominated from the agent cause, it is the predicament of “passion,” for to undergo is nothing but the undergoing of something from an agent. On the other hand, if the agent cause is denominated on account of its effect, one has the predicament of “action,” for action is an act from the agent into something else, as stated above.

In regard to measures, it will be either intrinsic or extrinsic. An intrinsic measure would be a thing’s own length and width and depth. In these cases, a subject is being denominated something by reason of what inheres intrinsically; hence, this pertains to the predicament “quantity.”

The extrinsic measures are time and place. It is the predicament “when” whenever something is denominated by time; when it is denominated by place, it is the predicament “where” or the predicament “position,” which adds to “where” the order of the parts in place. Such an order of parts is not considered in regard to the measure that is time, for the order of parts in time is already implied in the account of time, since time is the number of motion according to the order of the “before” and the “after.” Thus, it is through denomination from time or place that something is said to be “when” or “where.”

There is a special predicament for human beings. In other animals, nature provided the requirements for preserving life, such as horns for defense, a tough and woolly hide as a covering, and claws or the like for proceeding without harm. Hence, when animals are said to be “armed” or “covered” or “shod” by reason of this equipment, they are somehow so called not by reason of something extrinsic, but of something intrinsic, something that is part of them. Hence, such are referred to the predicament of “substance,” as the same would be if man were said to be endowed with hands or feet.

But the other things could not be endowed upon man by nature, both because they would be out of keeping with the precise balance of his constitution and because reason makes man capable of an enormous number of works, for the performance of which nature could not have endowed him with specific instruments. In the place of all these instruments, man has reason, which he can use to make for himself the things that are intrinsic to other animals. So, when a man is said to be armed or clothed or shod, he is denominated thus by reason of something extrinsic to him that is neither a cause nor a measure. Hence it is located in a special predicament called “habit.”

But we should not fail to note that this predicament is, in certain matters, used also for other animals, not inasmuch as they are considered in their nature, but insofar as they are put at the service of man. Thus we say that a horse is caparisoned or saddled or armed.

323. This makes it clear that, although motion is one, yet there are two predicaments that are based on motion, depending on the different external things according to which the predicamental denominations are made. For an agent is one thing from which, as from something external, the predicament of “passion” is taken; and the patient is some other thing from which something is denominated an agent. This solves the first difficulty.

324. The second doubt is easy to solve. For the account of motion depends not only on that which pertains to motion in reality but also on that which reason apprehends. In reality, motion is nothing more than an imperfect act, which is a sort of beginning of a perfect act in that which is being moved; thus, in that which is becoming white, some whiteness has begun to be. But, in order that what is imperfect have the account of motion, it is further required that we understand it as a mean between two. The one mentioned earlier is compared to motion as potency to act (hence motion is called act). The consequent one is compared to motion as the perfect to the imperfect or as act to potency; hence motion is called the act of a being that exists in potency, as we said above. (Lect. 2, n. 285.)

But anything imperfect, if it is not considered to be tending on to something other as perfect, is called the terminus of motion, and one will not have a motion according to which something is being moved—as, for example, if something should start to become white and then the alteration was immediately stopped.

Therefore, in regard to what there is of motion in external reality, motion is placed reductively in that genus that terminates the motion as the imperfect is reduced to the perfect, as stated above. (Lect. 1, n. 281.)

But, in regard to what reason apprehends about motion—namely, that it is midway between two terms—here the account of cause and effect are brought in, because, for something to be reduced from potency to act, an agent cause is required. From this aspect, motion pertains to the predicaments of “action” and “passion,” for these two predicaments are based on the accounts of acting cause and of effect, as was said above.

325. Then, at what motion is, then (202b23), he defines motion more particularly. He says that we have pointed out what motion is both in general and in particular—because, from what was said about the definition of motion in general, it is clear how it can be defined in particular. For if motion is the act of the mobile as such, it follows that alteration is the act of the alterable as alterable, and so on for other particular kinds of motion. And, because there was a doubt whether motion is an act of the mover or of the mobile—and we showed that it is an act of the active as from it and of the passive as in it—then, to remove any further doubts, we can say somewhat more explicitly that motion is an act of the potency of that which is active and of that which is passive. In this way, we could have said that building is an act of the builder and of the buildable as such. The same is true of healing and of other motions.