William Gibson said this quote
“ People who couldn't imagine themselves capable of evil were at a major disadvantage in dealing with people who didn't need to imagine, because they already were. She'd said it was always a mistake, to believe those people were different, special, infected with something that was inhuman, subhuman, fundamentally other. Which reminded her of what her mother had said about Corbell Picket. That evil wasn't glamorous, but just the result of ordinary half-assed badness, high school badness, given enough room, however that might happen, to become its bigger self. Bigger, with more horrible results, but never more than the cumulative weight of ordinary human baseness. ”