9. How do we get to know vice and virtue? As to virtue, we know it
by the very intelligence and by wisdom; for wisdom knows itself.
But how can we know vice? Just as we observe that an object is not
in itself straight, by applying a rule, so we discern vice by this
characteristic, that it does not comport itself with virtue. But do
we, or do we not have direct intuition thereof? We do not have the
intuition of absolute vice, because it is indeterminate. We know it,
therefore, by a kind of abstraction, observing that virtue is entirely
lacking. We cognize relative vice by noticing that it lacks some part
of virtue. We see a part of virtue, and, by this part, judging what is
lacking in order completely to constitute the form (of virtue), we
call vice what is lacking to it; defining as the indeterminate (evil)
what is deprived of virtue. Similarly with matter. If, for instance,
we notice a figure that is ugly because its ("seminal) reason," being
unable to dominate matter, has been unable to hide its deformity, we
notice ugliness by what is lacking to form.