Where does evil come from? Why do human do bad things? Is it part of out nature, just the way things are, or something we somehow chose, something we are fundamentally responsible for? Traditional Christian doctrine taught that there was a Fall, a world-historical catastrophe in which humanity rebelled against God, plunging the world into its current form: chaos filled and full of evil. But modern, Enlightened thinkers surely moved beyond such outdated ideas? Immanuel Kant, the greatest philosophical representative of the Enlightenment, upholder of the authority of reason and the supremacy of human autonomy, actually argued for a version of the Fall to explain human evil. That Kant took evil so seriously is itself important, but what do we make of his account, and what is its long-term significance?