They imagined that this was perfection, and their error on that score is among the most grievous of errors: first, because perfection does not reside in bare knowledge alone; second, because they allowed the soul no further increase of knowledge; third, because the knowledge they did allow is insufficient for true felicity; and fourth, because it contains elements of ignorance that contradict genuine knowledge—indeed, much, even most, of their discourse on matters divine is ignorance, not knowledge.

The point at issue here is that they granted the soul, once separated from the body, no perfection arising from love or volition, but only from knowledge itself. Then they blundered in yet another respect, for they made delight nothing but knowledge.

We clarify this by saying: The sixth line of argument is that happiness—meaning the delight, joy, and gladness the soul experiences through the insights it acquires—is not itself the knowledge; rather, it is something that comes about on the condition of knowledge. Knowledge is a prerequisite for it; it does not, of itself, necessitate it, much less constitute it. Their error is twofold: first, they supposed that mere knowledge necessarily produces delight; second, they identified delight with perception and knowledge, saying, “Delight is the perception of what is congenial insofar as it is congenial.” This is mistaken, for delight is not the very act of perception; it ensues after perception. A person, for instance, may crave food, then taste it and find it pleasurable: the delight is not the tasting itself but what arises because of the tasting.

Likewise, the various acts they classify as perception—hearing, sight, knowledge, and touch—are not themselves delight; they are only causes of delight, for hearing a melodious sound