Enneads II.5: Of the Aristotelian Distinction Between Actuality and Potentiality
Second Ennead, Book Five
Questions to Be Discussed
1. (Aristotle) spoke of (things) existing "potentially," and "actually"; and actuality is spoken of as a "being." We shall, however, have to examine this potential and actual existence; and whether this actual existence be the same as actuality, and whether this potential existence be identical with potentiality; also, whether these conceptions differ so that what exists actually be not necessarily actuality. It is evident that among sense-objects there exist things potentially. Are there also such among the intelligibles? This then is the problem: whether the intelligibles exist only actually; and on the hypothesis of the existence among intelligibles of something existing potentially, whether, because of its eternity, this always remains there in potentiality; and, because it is outside of time, never arrives to actuality.
Let us first define potentiality. When a thing is said to exist potentially, this means that it does not exist absolutely. Necessarily, what exists potentially is potential only in relation to something else; for example, metal is the statue potentially. Of course, if nothing were to be done with this thing, or within it, if it were not to become something beyond itself, if there were no possibility of its becoming anything else, it would only be what it was already. How could it then become something different from what it was? It did not, therefore, exist potentially. Consequently, if, on considering what is a thing that exists potentially, and one that exists actually, we say that it exists potentially, we must mean that it might become different from what it is, whether, after having produced this different thing, it remain what it is, or whether, on becoming this different thing, which it is potentially, it ceases being what it is itself. Indeed, if metal be a statue potentially, this is a relation different from water being metal potentially, as air is potentially fire.[15]
Shall we say that what thus exists potentially is potentiality in respect of what is to be; as, for instance, that the metal is the potentiality of a statue? Not so, if we refer to the producing potentiality; for the producing potentiality cannot be said to exist potentially. If, then, we identified existing potentially not only with existing actually, but also with actuality, then potentiality would coincide with potential existence. It would be better and clearer, therefore, to contrast potential existence with actual existence, and potentiality with actuality. The thing which thus exists potentially is the substance underlying the reactions, shapes and forms which it is naturally fitted to receive, to which it aspires for their betterment or deterioration, and for the destruction of those whose actualization constitutes differentiation.
2. As to matter, we shall have to examine whether it be something actually, while simultaneously it potentially is the shapes it receives; or whether it be nothing at all actually. Everything else of which we predicate potentiality passes on to actuality on receiving its form, and remaining the same. We may call a statue an actual statue, thus contrasting with it a potential statue; but an actual statue will not be implied by the metal which we called the potential statue. Consequently, what exists potentially does not become what exists actually; but from what was previously a potential (statue) proceeds what later is an actual (statue). Indeed, what exists actually is the compound, and not the matter; it is the form added to matter; this occurs when there is produced another being; when, for example, from the metal is made a statue; for the statue exists by this very being something other than the metal; namely, the compound.[17]