The generations from Art are those of which the Form is in the mind. By Form I mean the τ.η.ε. of each thing and its First Essence (τὴν πρώτην οὐσίαν, p. 1032, b. 1). For, in a certain way, the Form even of contraries is the same; since the essence of privation is the opposite essence: for example, health is the essence of disease; for disease is declared or described as absence of health, and health is the rational notion existing in the mind and in science. Now a healthy subject is generated by such an antecedent train of thought as follows (γίγνεται δὴ τὸ ὑγιὲς νοήσαντος οὕτως — b. 6):— Since health is so and so, there is necessity, if the subject is to attain health, that such and such things should occur, e.g., an even temperature of the body, for which latter purpose heat must be produced; and so on farther, until the thought rests upon something which is in the physician’s power to construct. The motion proceeding from this last thought is called Construction (b. 10), tending as it does towards health. So that, in a certain point of view, health may be said to be generated out of health, and a house out of a house; for the medical art is the form of health and the building art the form of the house: I mean the τ.η.ε., or the Essence without Matter, thereof (b. 14). Of the generations and motions here enumerated, one is called Rational Apprehension, viz., that one which takes its departure from the Principle and the Form; the other, Construction, viz., that which takes its departure from the conclusion of the process of rational apprehension (ἀπὸ τοῦ τελευταίου τῆς νοήσεως — b. 17). The like may be said about each of the intermediate steps: I mean, if the patient is to be restored to health, he must be brought to an even temperature. But the being brought to an even temperature, what is it? It is so and so; it will be a consequence of his being warmed. And this last again — what is it? So and so; which already exists potentially, since it depends upon the physician to produce it, the means being at his command (τοῦτο δ’ ἤδη ἐπ’ αὐτῷ — b. 21).
We see thus that the Constructive Agency (τὸ ποιοῦν) and the point from which the motion towards producing health takes its origin, is, when the process is one of Art, the Form present in the mind; and, when the process is one of Spontaneity, it proceeds from that which would be the first proceeding of the artist, if Art had been concerned. In the medical art, e.g., the artist begins by imparting warmth. He does this by rubbing. But this warmth might perhaps arise in the body without any such rubbing or interference by the artist. The warmth is the prime agent, in the case of spontaneous production. The warmth is either a part of health, or a condition to the existence of health, as bricks are to that of a house (p. 1032, b. 30).
Nothing can be generated, if nothing pre-existed — as has been already said before. Some part of what is generated must exist before: Matter pre-exists, as in-dwelling and not generated (ἡ γὰρ ὕλη μέρος· ἐνυπάρχει γὰρ καὶ γίγνεται αὕτη — p. 1033, a. 1. I do not understand these last words: it ought surely to be — ἐνυπάρχει γὰρ καὶ οὐ γίγνεται αὕτη. Bonitz’s explanation suits these last words better than it suits the words in the actual text.).
But something of the Form or rational explanation (τῶν ἐν τῷ λόγῳ) must also pre-exist. In regard to a brazen circle, if we are asked, Quid est? we answer in two ways: We say of the Matter — It is brass; We say of the Form — It is such and such a figure. And this is the genus in which it is first placed (p. 1033, a. 4).
The brazen circle has Matter in its rational explanation. But that which is generated, is called not by the name of the Matter out of which it is generated, but by a derivative name formed therefrom; not ἐκεῖνο, but ἐκείνινον. A statue is called not λίθος, but λίθινος. But, when a man is made healthy, he is not said to be the Matter out of which the health is generated; because that which we call the Matter is generated out of Privation along with the subject. Thus, both the man becomes healthy, and the patient becomes healthy; but the generation is more properly said to come out of Privation: we say, Sanus ex ægroto generatur, rather than, Sanus ex homine generatur (p. 1033, a. 12). In cases where the Privation is unmarked and unnamed, as, in the case of brass, privation of the spherical, or any other, figure, and, in the case of a house, the privation of bricks or wood, the work is said to be generated out of them like a healthy man out of a sick man (a. 14). Nevertheless the work is not called by the same name as the material out of which it is made, but by a paronym thereof; not ξύλον but ξύλινον (a. 18). In strict propriety, indeed, we can hardly say that the statue is made out of brass, nor the house out of wood; for the materia ex quâ ought to be something which undergoes change, not something which remains unchanged (a. 21).
It was remarked that in Generation there are three things or aspects to be distinguished —
1. Τὸ ὑφ’ οὗ, ὅθεν ἡ ἀρχὴ τῆς γενέσεως.
2. Τὸ ἐξ οὗ — rather ὕλη than στέρησις.
3. Τί γίγνεται.
Having already touched upon the two first, I now proceed to the third. What is it that is generated? Neither the Matter, nor the Form, but the embodiment or combination of the two. An artisan does not construct either the brass or the sphere, but the brazen sphere. If he be said to construct the sphere, it is only by accident (κατὰ συμβεβηκός), since the sphere in this particular case happens to be of brass. Out of the entire subject-matter, he constructs a distinct individual Something (p. 1033, a. 31). To make the brass round, is not to make the round, or to make the sphere, but to make a something different: that is the Form (of sphericity) embodied in another thing (a. 32). For, if the artisan made the round or the sphere, he must make them out of something different, pre-existing as a subject: e.g., he makes a brazen sphere, and in this sense — that he makes out of that Matter, which is brass, this different something, which is a sphere. If he made the sphere itself — the Form of sphere — he must make it out of some pre-existent subject; and you would thus carry back ad infinitum the different acts of generation and different pre-existent subjects (b. 4).