THE AGENT INTELLECT
NOW SINCE IN ALL NATURE THERE IS A FACTOR that is as matter in the genus, and is potentially all that is in the genus, and something else which is as cause and agent as making everything in it (thus art is related to its material): so there must be these differences in the soul. There is that intellect, which is such as being able to become everything; and there is that which acts upon everything, as a sort of state, like light; for light too, in a way, makes potential colours actual.§§ 728-31
And this is intellect separable, uncompounded and incapable of being acted on, a thing essentially in act. For the agent is always more excellent than the recipient, and the principle than its material.§§ 732-9
Knowledge in act is the same as the thing itself. But what is potential has temporal priority in the individual; yet this is not true universally, even with respect to time. Mind does not know at one time and not know at another time.§§ 740-1
Only separated, however, is it what it really is. And this alone is immortal and perpetual.§§ 742-3
It does not remember, because it is impassible; the passive intellect is corruptible, and the soul understands nothing apart from this latter. §§ 744-5