Evil as Privation

Evil is not a thing. It is the absence of a good that should be there.

Augustine's response to the problem of evil. Evil is not a positive substance created by a wicked god (the Manichaean view he renounced). It is privatio boni — the privation of good — like blindness is the absence of sight. This lets him hold a good God and the manifest existence of evil in the same theology. Aquinas will systematize the move.