1 But let us return to the fore-mentioned question as to the production [of the Æons]. And, in the first place, let them tell us the reason of the production of the Æons being of such a kind that they do not come in contact with any of those things which belong to creation. For they maintain that those things [above] were not made on account of creation, but creation on account of them; and that the former are not images of the latter, but the latter of the former. As, therefore, they render a reason for the images, by saying that the month has thirty days on account of the thirty Æons, and the day twelve hours, and the year twelve months, on account of the twelve Æons which are within the Pleroma, with other such nonsense of the same kind, let them now tell us also the reason for that production of the Æons, why it was of such a nature, for what reason the first and first-begotten Ogdoad was sent forth, and not a Pentad, or a Triad, or a Septenad, or any one of those which are defined by a different number? Moreover, how did it come to pass, that from Logos and Zoe were sent forth ten Æons, and neither more nor less; while again from Anthropos and Ecclesia proceeded twelve, although these might have been either more or less numerous?
2. And then, again, with reference to the entire Pleroma, what reason is there that it should be divided into these three — an Ogdoad, a Decad, and a Duodecad— and not into some other number different from these? Moreover, with respect to the division itself, why has it been made into three parts, and not into four, or five, or six, or into some other number among those which have no connection with such numbers as belong to creation? For they describe those [Æons above] as being more ancient than these [created things below], and it behooves them to possess their principle [of being] in themselves, one which existed before creation, and not after the pattern of creation, all exactly agreeing as to the point.
3. The account which we give of creation is one harmonious with that regular order [of things prevailing in the world], for this scheme of ours is adapted to the things which have [actually] been made; but it is a matter of necessity that they, being unable to assign any reason belonging to the things themselves, with regard to those beings that existed before [creation], and were perfected by themselves, should fall into the greatest perplexity. For, as to the points on which they interrogate us as knowing nothing of creation, they themselves, when questioned in turn respecting the Pleroma, either make mention of mere human feelings, or have recourse to that sort of speech which bears only upon that harmony observable in creation, improperly giving us replies concerning things which are secondary, and not concerning those which, as they maintain, are primary. For we do not question them concerning that harmony which belongs to creation, nor concerning human feelings; but because they must acknowledge, as to their octiform, deciform, and duodeciform Pleroma (the image of which they declare creation to be), that their Father formed it of that figure vainly and thoughtlessly, and must ascribe to Him deformity, if He made anything without a reason. Or, again, if they declare that the Pleroma was so produced in accordance with the foresight of the Father, for the sake of creation, as if He had thus symmetrically arranged its very essence, then it follows that the Pleroma can no longer be regarded as having been formed on its own account, but for the sake of that [creation] which was to be its image as possessing its likeness (just as the clay model is not moulded for its own sake, but for the sake of the statue in brass, or gold, or silver about to be formed), then creation will have greater honour than the Pleroma, if, for its sake, those things [above] were produced.
Source: Adversus haereses (New Advent)