Plotinos: Complete Works, v. 1 In Chronological Order,...

The soul imparts unity to all things when producing them, fashioning them, and forming them. Should we, therefore, after rising to the Soul, say that she not only imparts unity, but herself is unity in itself? Certainly not. The soul that imparts form and figure to bodies is not identical with form, and figure. Therefore the soul imparts unity without being unity. She unifies each of her productions only by contemplation of the One, just as she produces man only by contemplating Man-in-himself, although adding to that idea the implied unity. Each of the things that are called "one" have a unity proportionate to their nature ("being"); so that they participate in unity more or less according as they share essence188 (being). Thus the soul is something different from unity; nevertheless, as she exists in a degree higher (than the body), she participates more in unity, without being unity itself; indeed she is one, but the unity in her is no more than contingent. There is a difference between the soul and unity, just as between the body and unity. A discrete quantity such as a company of dancers, or choric ballet, is very far from being unity; a continuous quantity approximates that further; the soul gets still nearer to it, and participates therein still more. Thus from the fact that the soul could not exist without being one, the identity between the soul and unity is suggested. But this may be answered in two ways.

First, other things also possess individual existence because they possess unity, and nevertheless are not unity itself; as, though the body is not identical with unity, it also participates in unity. Further, the soul is manifold as well as one, though she be not composed of parts. She possesses several faculties, discursive reason, desire, and perception—all of them faculties joined together by unity as a bond. Doubtless the soul imparts unity to something else (the body), because she herself possesses unity; but this unity is by her received from some other principle (namely, from unity itself).