Note (return) — Chapter XII

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