live, rather than the system of immutable and timeless ‘laws’ which we devise for its explanation. Hence Plato’s changeless οὐσίαι seem to him too distant and divorced to explain the world. An οὐσία which is not immanent and does not assert itself in the world of phenomena, but remains an inert and secluded δύναμις, is lifeless and worthless. Hence the καθόλου must be in the world and pervade it; or, in his technical phrase, must display itself in actuality (ἐνεργεία). Not that Aristotle denies the validity of the considerations which led Plato to frame his conception of οὐσία; he denies only its adequacy. The highest conception must be Ἐνέργεια and not Δύναμις, the actual functioning of a substance whose real nature is only so revealed.
This is the ultimate reason why Aristotle denies that ἀρετή is the Good, and contends that Ἐυδαιμονία must be ἐνέργεια κατ’ ἀρετήν. A merely statical treatment of the truly valuable will not suffice: the Good is not merely ἀγαθὴ φύσις, it is ἀγαθὴ φύσις in exercise, and a ἕξις is only valuable as the basis and potentiality of an ἐνέργεια.
It follows from this rehabilitation of the Process-view of the world that Aristotle has (a) to establish the superiority of his conception of ἐνέργεια over the Platonic conception of οὐσία, (b) that he has to distinguish it from the conception of κίνησις or γένεσις, which had succumbed to the Platonic criticism.
The first point is of course easy enough to establish. It suffices to point out that a substance apart from its activity is an abstraction (= ‘without causality no substantiality’); or, in Aristotle’s words, that the actuality is naturally prior to the potentiality, that to be is to be active.[1]
The second point is more difficult, and Aristotle’s proof thereof is apt to appear paradoxical to us because of our inveterate habit of regarding a ‘function’ (ἐνέργεια) as a sort of ‘process’ (γένεσις), or even—when we try to be particularly ‘scientific’—as ultimately reducible to a sort of ‘motion’. In other words, we ordinarily subsume Aristotle’s ἐνέργεια under the conception of what he would have called κίνησις. But this is the precise opposite of the device whereby Aristotle turned the flank of the Platonic criticism and established his own conception of Ἐνέργεια. Instead of classifying ἐνέργεια under κίνησις, he simply makes ἐνέργεια
- ↑ Cf., esp. Eth. Nich., ix., 7, 4 (1168 a 6) ἐσμὲν δ’ ἐνέργεια.
