Here is one of M.C. Escher’s symmetry drawings. Look at the white spaces and you see angels. Look at the dark spaces and you see devils.
It’s like humans. ‘Normal’ people turn into monsters. The person you least expect to do something courageous becomes a hero. How does this happen? The American psychologist Philip Zimbardo proposes an explanation in his TED talk from 2008.
Philip Zimbardo is the American psychologist who led the controversial Stanford Prison Experiment in 1971. In that experiment, college students were assigned to be “guards” or “prisoners” in a mock prison. They quickly began acting out their roles. The experiment had to be stopped after six days.
Zimbardo was an expert witness at Abu Ghraib. His books include The Lucifer Effect, which explores the nature of evil.