Enneads III.6: Of the Impassibility of Incorporeal Entities (Soul and and Matter)
The Myth of the Ithyphallic Hermes
That no doubt was the meaning of those ancient sages who in mysteries and initiations symbolically represented the "ancient Hermes"[95] with the generative organ in erection, to teach that it is intelligible reason that begets sense-objects. On the other hand, these same sages signify the sterility of matter, condemned to perpetual self-identity, by the eunuchs who surround Rhea,[96] making of it the mother of all things, to use the expression they employ in designating the principle that plays the part of substrate.