1. Studying the origin of evils that might affect all beings in
general, or some one class in particular, it is reasonable to begin by
defining evil, from a consideration of its nature. That would be the
best way to discover whence it arises, where it resides, to whom it may
happen, and in general to decide if it be something real. Which one of
our faculties then can inform us of the nature of evil? This question
is not easy to solve, because there must be an analogy between the
knower and the known.[157] The Intelligence and the Soul may indeed
cognize forms and fix their desires on them, because they themselves
are forms; but evil, which consists in the absence of all goods, could
not be described as a form.[158] But inasmuch as there can be but one
single science, to embrace even contraries, and as the evil is the
contrary of the good, knowledge of the good implies that of evil.
Therefore, to determine the nature of evil, we shall first have to
determine that of good, for the higher things must precede the lower,
as some are forms and others are not, being rather a privation of the
good. Just in what sense evil is the contrary of the good must also be
determined; as for instance, if the One be the first, and matter the
last;[159] or whether the One be form, and matter be its absence. Of
this further.[160]