[Footnote 730: ][ (return) ] Id., ib., vol. i. p. 185.
The relation of actuality to potentiality is the subject of an extended and elaborate discussion in book viii., the general results of which may be summed up in the following propositions:
1. The relation of Actuality to Potentiality is as the Perfect to the Imperfect.--The progress from potentiality to actuality is motion or production (κίνησις or γένεσις). But this motion is transitional, and in itself imperfect--it tends towards an end, but does not include the end in itself. But actuality, if it implies motion, has an end in itself and for itself; it is a motion desirable for its own sake. [731] The relation of the potential to the actual Aristotle exhibits by the relation of the unfinished to the finished work, of the unemployed builder to the one at work upon his building, of the seed-corn to the tree, of the man who has the capacity to think, to the man actually engaged in thought. [732] Potentially the seed-corn is the tree, but the grown-up tree is the actuality; the potential philosopher is he who is not at this moment in a philosophic condition; indeed, every thing is potential which possesses a principle of development, or of change. Actuality or entelechy, on the other hand, indicates the perfect act, the end gained, the completed actual; that activity in which the act and the completeness of the act fall together--as, for example, to see, to think, where the acting and the completed act are one and the same.
2. The Relation of Actuality to Potentiality is a causal Relation.--A thing which is endued with a simple capacity of being may nevertheless not actually exist, and a thing may have a capacity of being and really exist. Since this is the case, there must ensue between non-being and real being some such principle as energy, in order to account for the transition or change. [733] Energy has here some analogy to motion, though it must not be confounded with motion. Now you can not predicate either motion or energy of things which are not. The moment energy is added to them they are. This transition from potentiality to actuality must be through the medium of such principles as propension or free will, because propension or free will possess in themselves the power of originating motion in other things. [734]
[Footnote 731: ][ (return) ] "Metaphysics," bk. viii. ch. vi.
[Footnote 732: ][ (return) ] Ibid., bk. viii. ch. vi.
[Footnote 733: ][ (return) ] Ibid., bk. viii. ch. iii.
[Footnote 734: ][ (return) ] Ibid., bk. viii. ch. v.
3. The Relation of Actuality and Potentiality is a Relation of Priority.--Actuality, says Aristotle, is prior to potentiality in the order of reason, in the order of substance, and also (though not invariably) in the order of time. The first of all capacities is a capacity of energizing or assuming a state of activity; for example, a man who has the capacity of building is one who is skilled in building, and thus able to use his energy in the art of building. [735] The primary energizing power must precede that which receives the impression of it, Form being older than Matter. But if you take the case of any particular person or thing, we say that its capacity of being that particular person or thing precedes its being so actually. Yet, though this is the case in each particular thing, there is always a foregone energy presumed in some other thing (as a prior seed, plant, man) to which it owes its existence. One pregnant thought presents itself in the course of the discussion which has a direct bearing upon our subject. Δὑναµιϛ has been previously defined as "a principle of motion or change in another thing in so far forth as it is another thing" [736]--that is, it is fitted by nature to have motion imparted to it, and to communicate motion to something else. But this motion wants a resting-place. There can be no infinite regression of causes. There is some primary δύναµιϛ presupposed in all others, which is the beginning of change. This is Φύσις, or nature. But the first and original cause of all motion and change still precedes and surpasses nature. The final cause of all potentiality is energy or actuality. The one proposed is prior to the means through which the end is accomplished. A process of actualization, a tendency towards completeness or perfection (τέλοϛ) presupposes an absolute actuality which is at once its beginning and end. "One energy is invariably antecedent to another in time, up to that which is primarily and eternally the Moving Cause." [737]
[Footnote 735: ][ (return) ] "Metaphysics," bk. viii. ch. viii.