The Six Books of Proclus on the Theology of Plato, Volume 2

For if every intellect is impartible, and the multitude which is in it is united through intellectual impartibility, all things in it will be in one, impartibles will be united to each other, and all intellectual forms will pervade through all. But if all intellectual forms subsist immaterially and incorporeally, they are unconfused with each other and separate, and each preserving its own purity, remains that which it is. The peculiar participation however of each participating in a separate manner, manifests the unconfused nature of intellectual forms. For unless the forms which are participated were distinguished separate from each other, the participants of each of them would not participate in a separate manner, but in the subordinate natures [i.e. in the participants] there would be, in a much greater degree, an indistinct confusion, these being according to their order of an inferior condition. For whence would there be a separation of these, if the natures which give subsistence to, and perfect them, were without distinction, and were confused together? But again the impartible hypostasis, and uniform essence of that which contains forms, evinces their united nature. For things which have their hyparxis in the impartible and the uniform, are impartibly in the same thing. For how can you divide the impartible and the one? Hence, they have a simultaneous subsistence, and are in each other, each wholly pervading through the whole of each, in a manner unaccompanied with interval.

For that which comprehends them is not extended with interval, nor is one of them in this thing, but another elsewhere, as in that which has interval; but every thing is at once in the impartible and in one. So that all intellectual forms are in each other, and are in each other unitedly, and at the same time each is distinctly apart from each.

But if some one, in addition to these demonstrations, should require also examples, let him direct his attention to the theorems which exist in one soul. For all these are in the same essence, which is truly without magnitude,[297] and are united to each other. For that which is without magnitude, does not locally contain the things which are in it, but the natures which it contains are united and separated, impartibly and without interval. For the soul genuinely produces all things, and each apart from each, attracting nothing from the rest, which, unless they were always separated according to habit, would not be separated by the energy of the soul.