Abstract
Scholars have failed to adequately distinguish Kant’s grades of evil:
frailty (weakness of will), impurity, and depravity. I argue that the only way to
distinguish them is, f irstly, to recognize that frailty is explicitly, practically irrational
and not caused by any sort of self-deception. Instead, it is caused by the
radical evil that Kant finds within the character of all persons. Secondly, impurity
can only be understood to be self-deception either about the nature of the act
itself, which results in an epistemic error, or about one’s motivations for following
a properly reasoned, moral conclusion, which results in a motivational error.
Thirdly, depravity is self-deception about morality itself, by which the agent believes
that it is morally right to follow self-love.