Enneads II.5: Of the Aristotelian Distinction Between Actuality and Potentiality
In Permanent Things, Potentiality and Actuality May Coincide
In non-permanent things, what exists potentially is evidently something quite different (from what is said to exist actually). But when the potential grammarian becomes an actual grammarian, why should not the potential and actual coincide? The potential wise Socrates is the same as the actual Socrates. Is the ignorant man, who was potentially learned, the same as the learned? No: only accident makes of the ignorant man a learned one; for it was not his ignorance that made him potentially wise; with him, ignorance was only an accident; but his soul, being by herself disposed (to be actually learned), still remains potentially learned, in so far as she was actually so, and still keeps what is called potential existence; thus the actual grammarian does not cease being a potential grammarian.[18] Nothing hinders these two different things (of being a potential and actual grammarian) from coinciding; in the first case, the man is no more than a potential grammarian; in the latter, the man is still a potential grammarian, but this potentiality has acquired its form (that is, has become actual[19]).
If however what is potential be the substrate, while the actual is both (potential and actual) at the same time, as in the (complete) statue, what then shall we call the form in the metal? We might well call the actuality by which some object exists actually, and not merely potentially, the form and shape; therefore not merely actuality, but the actuality of this individual thing.