Act, Actual, opposed to
Virtual in the
old sense of the latter term.
Actus is the Latin word employed by the schoolmen as an equivalent to
the ἐνέργεια of Aristotle, and potentialitas stands with them for his
As he spoke of things that are
δὐναμει and things that are
they of things in potentiâ and things in actu. The latter term has
survived in the adjective actual and the adverb actually. In our older
writers, however, the substantive act was used, not as with us, for an
individual action, but in the technical sense of the Aristotelian
philosophy. For example, take this sentence of Hooker: "God alone
excepted, who actually and everlastingly is whatsoever He may be, and
which cannot hereafter be that which now He is not; all other things are
somewhat in possibility, which as yet they are not in act."(1)
This distinction between existing
δὐναμει and existing
an important place in Aristotelian philosophy. He illustrates it by
referring to the presence
δὐναμει of the statue in the marble, as
opposed to the sculptured Mercury existing ἐνέργεια, to the half in the
whole which can be separated from it, and then have an actual existence
of its own, to wakefulness in him that is asleep which has a potential
but not an actual reality, and the like.
Potentiality must not be identified with possibility. In possessing
these distinct terms Latin terminology has an advantage over Greek,
unless indeed we see the same distinction in the two words
ἐνδεχομενός, when the latter is used in opposition to necessary. Though
he is thrown on the word
δύναμει and the adjective
δυνατός, Aristotle is
careful to note that nothing exists
δύναμει of which the subject is not
susceptible. Thus light has no potential existence in an inanimate
thing, the finished statue none in water. Whereas anything is in one
sense possible that does not involve contradiction.
Virtuality were formerly synonymous with potential and
potentiality. How these words came by their present, so different from
their original, meaning, I know not. Johnson seemed aware of none but
the present use, and failed to see that in the majority of his
quotations the word is employed in its original one.
As there can be nothing potential in God, nothing that He might be, but
is not, it has been well said that He is pure act.
The whole distinction between the potential and the actual
is pregnant with consequence. It took a leading share in the theological
controversies of the sixth century, and bears, as may be easily seen, on
the whole question of original sin as distinguished from actual, the
former being sin δύναμει, and the latter, as its name shows,
sin ἐνέργεια. It also enters into the subject of Nominalism and Realism.
Perhaps its aid might tend to an adjustment of that dispute. "The
species is potentially in the genus, the genus is actually in the species."(2) On the same principle we must say that the
individual the res is potentially in the universal, the universal is
actually in the individual. The genus energises in species, the species
in the specimen, the universal in the individual. The difference between
Aristotle's and the modern employment of the word energy must be
carefully kept in mind. Even in his own day, however, it would appear
that he used it in a wider sense than the ordinary.
Έπὶ πλέον γάρ ἐστω ή δύναμις καὶ ή
ἐνέργεια τῶν μόνον λεγομένων κατὰ κίνησιν.(3) This remark
would have been needless had the case been otherwise. In his use,
however, οὺ μονον κινήσεώς ἐστιν
ἐνέργεια ἀλλὰ καὶ ἀκινησίας.
(1) Eccl. Pol. book I. v. 1.
(2) Lord Monboddo.
(3) Metaph. VIII. 1.