Does the concept of evil mark out a distinctive moral reality? Or does it merely record an inclination to demonise severe moral transgression? Here is one way to get a grip on the question. We distinguish different ways in which things are terrible for us. Pain, suffering, loss, death and disease are terrible in one way. Murder, torture, cruelty and a malevolent will are terrible in another. Let the first category go unnamed for the time being. The second answers to the name of morality. So one way of rephrasing my opening question would be to ask: does evil mark out a distinc­ tive and irreducible kind of moral terribleness? The question is often in the air when there is discussion of the atrocities of our century. During such discussions some people speak without hesitation of the evil of those atrocities. Others, and sometimes the same people at other times, show themselves uneasy with talk of evil.