All ‘Nature’, even in the lowest, is in ceaseless Contemplation and Aspiration: while every being, until the ultimate possible is reached, tends to engender an image of itself, it tends also to rejoin the next highest, of which it is itself a shadow or lower manifestation: even Matter, all but outcast from the sphere of Being and unable to engender, has the power of receiving form and is, thereby, tending feebly towards Authentic-Existence, towards Soul and Mind, and so is linked, distantly, with the Divine.
Authentic-Existent, -Existents, -Existence represent what is usually conveyed by the English philosophical term Real-Being. This choice was made, mainly, on considerations of literary convenience: an original writer can so play with his sentence-construction as to avoid the awkward clash between the noun and participle; a translator works more freely when there is no possibility of this clash.
It happens, moreover, that the adopted term is in itself better, at least for Plotinian uses: Real-Being carries some undesirable suggestion of the purely abstract; ‘The Authentic-Existent’ comports something of the notion of Person or Individuality in an august sense and, so, is often, though not by any means always, nearer to the Plotinian notion. The need of some such departure from the customary term was suggested by Mr Meade’s use of the emphatic ‘That which is’ for the same notion; Mr Meade’s term was rejected only because it sounds a little grandiose, does not pack conveniently into every sentence, and has no handy plural.
As for Plotinus’ use of the idea, it must be pointed out that it represents most often the very superlative of altitude but sometimes is employed in a derogatory sense: the Sphere of Existence is often The Intellectual-and-Intelligible-Cosmos, Divine Mind, or in general The Divine; sometimes, however, it means the realm of process or of ‘Becoming’, as opposed to the stately immobility of the Divine Beings, then considered as collectively Supra-Existents.