1 I now proceed to show, as follows, that the first order of production, as conceived of by them, must be rejected. For they maintain that Nous and Aletheia were produced from Bythus and his Ennœa, which is proved to be a contradiction. For Nous is that which is itself chief, and highest, and, as it were, the principle and source of all understanding. Ennœa, again, which arises from him, is any sort of emotion concerning any subject. It cannot be, therefore, that Nous was produced by Bythus and Ennœa; it would be more like the truth for them to maintain that Ennœa was produced as the daughter of the Propator and this Nous.
For Ennœa is not the daughter of Nous, as they assert, but Nous becomes the father of Ennœa. For how can Nous have been produced by the Propator, when he holds the chief and primary place of that hidden and invisible affection which is within Him? By this affection sense is produced, and Ennœa, and Enthymesis, and other things which are simply synonyms for Nous himself. As I have said already, they are merely certain definite exercises in thought of that very power concerning some particular subject.
We understand the [several] terms according to their length and breadth of meaning, not according to any [fundamental] change [of signification]; and the [various exercises of thought] are limited by [the same sphere of] knowledge, and are expressed together by [the same] term, the [very same] sense remaining within, and creating, and administering, and freely governing even by its own power, and as it pleases, the things which have been previously mentioned.
Source: Adversus haereses (New Advent)