1 They proceed to tell us that the Propator of their scheme was known only to Monogenes, who sprang from him; in other words, only to Nous, while to all the others he was invisible and incomprehensible. And, according to them, Nous alone took pleasure in contemplating the Father, and exulting in considering his immeasurable greatness; while he also meditated how he might communicate to the rest of the Æons the greatness of the Father, revealing to them how vast and mighty he was, and how he was without beginning—beyond comprehension, and altogether incapable of being seen. But, in accordance with the will of the Father, Sige restrained him, because it was his design to lead them all to an acquaintance with the aforesaid Propator, and to create within them a desire of investigating his nature. In like manner, the rest of the Æons also, in a kind of quiet way, had a wish to behold the Author of their being, and to contemplate that First Cause which had no beginning.
Source: Adversus haereses (New Advent)