Commentary on Aristotle's Metaphysics

 PROLOGUE

 BOOK I

 LESSON 1

 LESSON 2

 LESSON 3

 LESSON 4

 LESSON 5

 LESSON 6

 LESSON 7

 LESSON 8

 LESSON 9

 LESSON 10

 LESSON 11

 LESSON 12

 LESSON 13

 LESSON 14

 LESSON 15

 LESSON 16

 LESSON 17

 BOOK II

 LESSON 1

 LESSON 2

 LESSON 3

 LESSON 4

 LESSON 5

 BOOK III

 LESSON 1

 LESSON 2

 LESSON 3

 LESSON 4

 LESSON 5

 LESSON 6

 LESSON 7

 LESSON 8

 LESSON 9

 LESSON 10

 LESSON 11

 LESSON 12

 LESSON 13

 LESSON 14

 LESSON 15

 BOOK IV

 LESSON 1

 LESSON 2

 LESSON 3

 LESSON 4

 LESSON 5

 LESSON 6

 LESSON 7

 LESSON 8

 LESSON 9

 LESSON 10

 LESSON 11

 LESSON 12

 LESSON 13

 LESSON 14

 LESSON 15

 LESSON 16

 LESSON 17

 BOOK V

 LESSON 1

 LESSON 2

 LESSON 3

 LESSON 4

 LESSON 5

 LESSON 6

 LESSON 7

 LESSON 8

 LESSON 9

 LESSON 10

 LESSON 11

 LESSON 12

 LESSON 13

 LESSON 14

 LESSON 15

 LESSON 16

 LESSON 17

 LESSON 18

 LESSON 19

 LESSON 20

 LESSON 21

 LESSON 22

 BOOK VI

 LESSON 1

 LESSON 2

 LESSON 3

 LESSON 4

 LESSON 1

 LESSON 2

 LESSON 3

 LESSON 4

 LESSON 5

 LESSON 6

 LESSON 7

 LESSON 8

 LESSON 9

 LESSON 10

 LESSON 11

 LESSON 12

 LESSON 13

 LESSON 14

 LESSON 15

 LESSON 16

 LESSON 17

 BOOK VIII

 LESSON 1

 LESSON 2

 LESSON 3

 LESSON 4

 LESSON 5

 LESSON 1

 LESSON 2

 LESSON 3

 LESSON 4

 LESSON 5

 LESSON 6

 LESSON 7

 LESSON 8

 LESSON 9

 LESSON 10

 LESSON 11

 BOOK X

 LESSON 1

 LESSON 2

 LESSON 3

 LESSON 4

 LESSON 5

 LESSON 6

 LESSON 7

 LESSON 8

 LESSON 9

 LESSON 10

 LESSON 11

 LESSON 12

 Book XI

 LESSON 1

 LESSON 2

 LESSON 3

 LESSON 4

 LESSON 5

 LESSON 6

 LESSON 7

 LESSON 8

 LESSON 9

 LESSON 10

 LESSON 11

 LESSON 12

 LESSON 13

 BOOK XII

 LESSON 1

 LESSON 2

 LESSON 3

 LESSON 4

 LESSON 5

 LESSON 6

 LESSON 7

 LESSON 8

 LESSON 9

 LESSON 10

 LESSON 11

 LESSON 12

 Footnotes

LESSON 7

The Conceptual and Temporal Priority of Actuality

to Potency and Vice Versa

Chapter 8: 1049b 4-1050a 3

             778. Since we have established the different senses in which the term prior is employed (457), it is evident that actuality is prior to potency. And by potency I mean not only that definite kind which is said to be a principle of change in another thing inasmuch as it is other, but in general every principle of motion or rest. For nature also belongs to the same thing, since it is in the same genus as potency; for it is a principle of motion, although not in another thing but in something inasmuch as it is the same. Therefore actuality is prior to all such potency both in intelligibility and in substance; and in time it is prior in one sense, and in another it is not.

             779. It is evident, then, that actuality is prior to potency in intelligibility; for what is potential in a primary sense is potential because it is possible for it to become actual. I mean, for example, that it is what is capable of building that can build, and what is capable of theorizing that can theorize, and what is capable of being seen that can be seen. And the same reasoning also applies in the case of other things; and therefore it is necessary that the conception or knowledge of the one should precede that of the other.

             780. And actuality is prior to potency in time in the sense that an actuality which is specifically but not numerically the same as a potency is prior to it. I mean that the matter and the seed and the thing capable of seeing, which are a man and grain and seeing potentially but not yet actually, are prior in time to this man and to grain and to the act of seeing which exist actually. But prior to these are other actually existing things from which these have been produced; for what is actual is always produced from something potential by means of something which is actual. Thus man comes from man and musician from musician; for there is always some primary mover, and a mover is already something actual. And in our previous discussions (598; 611) concerning substance it was stated that everything which comes to be is produced from something, and this is specifically the same as itself.

             781. And for this reason it seems to be impossible that anyone should be a builder who has not built something, or that anyone should be a harpist who has not played the harp. And the same holds true of all others who are learning; for one who is learning to play the harp learns to play it by playing it. And the same holds true in other cases.

             782. From this arose the sophistical argument that one who does not have a science will be doing the thing which is the object of this science; for one who is learning a science does not have it.

             783. But since some part of what is coming to be has come to be, and in general some part of what is being moved has been moved (as became evident in our discussions on motion , perhaps one who is learning a science must have some part of that science. Hence it is also clear from this that actuality is prior to potency both in the process of generation and in time.

COMMENTARY

             1844. Having established the truth about potency and actuality, the Philosopher now compares one with the other; and this is divided into two parts. In the first part (778:C 1844) he compares them from the viewpoint of priority and posteriority; in the second (801:C 1883), in terms of being better or worse ("Furthermore, that"); and in the third (805:C 1888), in reference to knowledge of the true and the false ("And it is").

             In regard to the first he does two things. First, he explains his aim, saying that, since it has been established above, in Book V (457:C 936), that the term prior is used in different senses, it is evident that actuality is prior to potency in different ways. And we are now speaking of potency not only inasmuch as it is a principle of motion in some other thing as other, as active potency was defined above (743:C 1776), but universally of every principle, whether it be a principle that causes motion or a principle of immobility or rest or a principle of action devoid of motion (e.g., understanding), because nature also seems to belong to the same thing as potency.

             1845. For nature is in the same genus as potency itself because each is a principle of motion, although nature is not a principle of motion in some other thing but in the thing in which it is present as such, as is made clear in Book II of the Physics. However, nature is a principle not only of motion but also of immobility. Hence actuality is prior to all such potency both in intelligibility and in substance. And in one sense it is also prior in time, and in another it is not.

             1846. It is evident (779).

             Second he proves his thesis. First (779:C 1846), he shows that actuality is prior to potency in intelligibility. Second (780:C 1847), he shows how it is prior in time, and how it is not ("And actuality"). Third (784:C 1856), he shows how it is prior in substance ("But actuality").

             The first is proved as follows: anything that must be used in defining something else is prior to it in intelligibility, as animal is prior to man and subject to accident. But potency or capability can only be defined by means of actuality, because the first characteristic of the capable consists in the possibility of its acting or being actual. For example, a builder is defined as one who can build, and a theorist as one who can theorize, and the visible as what can be seen; and the same is true in other cases. The concept of actuality must therefore be prior to the concept of potency, and the knowledge of actuality prior to the knowledge of potency. Hence Aristotle explained above what potency is by defining it in reference to actuality, but he could not define actuality by means of something else but only made it known inductively.

             1847. And actuality (780).

             Then he shows how actuality is prior to potency in time, and how it is not. In regard to this he does two things. First (780), he makes this clear in the case of passive potencies; and second (781:C 1850), in the case of certain active potencies ("And for this reason").

             He accordingly says, first (780), that actuality is prior to potency in time in the sense that in the same species the agent, or what is actual, is prior to what is potential; but in numerically one and the same thing what is potential is prior in time to what is actual.

             1848. This is shown as follows: if we take this man who is now actually a man, prior to him in time there was a matter which was potentially a man. And similarly seed, which is potentially grain, was prior in time to what is actually grain. And "the thing capable of seeing," i.e., having the power of sight, was prior in time to the thing actually seeing. And prior in time to the things having potential being there were certain things having actual being, namely, agents, by which the former have been brought to actuality. For what exists potentially must always be brought to actuality by an agent, which is an actual being. Hence what is potentially a man becomes actually a man as a result of the man who generates him, who is an actual being; and similarly one who is potentially musical becomes actually musical by learning from a teacher who is actually musical. And thus in the case of anything potential there is always some first thing which moves it, and this mover is actual. It follows, then, that even though the same thing numerically exists potentially prior in time to existing actually, there is still also some actual being of the same species which is prior in time to the one that exists potentially.

             1849. And because someone could be perplexed about some of the statements which he had made, he therefore adds that these have been explained above; for it was pointed out in the foregoing discussions about substance--in Book VII (599:C 1383; 611:C 1417)--that everything which comes to be comes from something as matter, and by something as an agent. And it was also stated above that this agent is specifically the same as the thing which comes to be. This was made clear in the case of univocal generations, but in the case of equivocal generations there must also be some likeness between the generator and the thing generated, as was shown elsewhere (617:C 1444-47).

             1850. And for this reason (781).

             He explains the temporal sequence of actuality and potency in the case of certain active potencies; and in regard to this he does three things.

             First, he explains what he intends to do. For it was said above (761:C 1815) that there are certain operative potencies whose very actions must be understood to be performed or exercised beforehand, as those acquired by practice or instruction. And with regard to these he says here that in those things which are numerically the same, actuality is also prior to potency. For it seems impossible that anyone should become a builder who has not first built something; or that anyone should become a harpist who has not first played the harp.

             1851. He draws this conclusion from the points laid down above; for it was said above (780:C 1848) that one who is potentially musical becomes actually musical as a result of someone who is actually musical--meaning that he learns from him; and the same thing holds true of other actions. Now one could not learn an art of this kind unless he himself performed the actions associated with it; for one learns to play the harp by playing it. This is also true of the other arts. It has been shown, then, that it is impossible to have potencies of this sort unless their actions are also first present in one and the same subject numerically.

             1852. From this arose (782).

             Second, he raises a sophistical objection against the above view. He says that "a sophistical argument arose," i.e., an apparently cogent syllogism which contradicts the truth, and it runs as follows: one who is learning an art exercises the actions of that art. But one who is learning an art does not have that art. Hence one who does not have a science or an art is doing the thing which is the object of that science or art. This seems to be contrary to the truth.

             1853. But since some (783).

             Third, he answers this objection by stating a position which was discussed and proved in the Physics, Book VI; for there he proved that being moved is always prior to having been moved, because of the division of motion. For whenever any part of a motion is given, since it is divisible, we must be able to pick out some part of it which has already been completed, while the part of the motion given is going on. Therefore whatever is being moved has already been partly moved.

             1854. And by the same argument, whatever is coming to be has already partly come to be; for even though the process of producing a substance, with reference to the introduction of the substantial form, is indivisible, still if we take the preceding alteration whose terminus is generation, the process is divisible, and the whole process can be called a production. Therefore, since what is coming to be has partly come to be, then what is coming to be can possess to some degree the activity of the thing in which the production is terminated. For example, what is becoming hot can heat something to some degree, but not as perfectly as something that has already become hot. Hence, since to learn is to become scientific, the one learning must already have, as it were, some part of a science or an art. It is not absurd, then, if he should exercise the action of an art to some degree; for he does not do it as perfectly as one who already has the art.

             1855. But in reason itself there are also naturally inherent certain seeds or principles of the sciences and virtues, through which a man can pass to some degree into the activity of a science or a virtue before he has the habit of the science or the virtue; and when this has been acquired he acts perfectly, whereas at first he acted imperfectly. Lastly he summarizes the above discussion, as is evident in the text.