Slide into evil. In the Stanford Prison Study in 1971, university students were randomly assigned to be prisoners or guards and then placed in a mock prison setting in the basement of the campus psych building. The guards became so oppressive and sadistic, and the prisoners so passive and depressed, that the two-week study was ended after six days. Lead researcher Philip Zimbardo  is featured on edge.org in a lengthy discussion of evil and heroism. He calls the study a "cautionary tale of the many ways in which good people can be readily and easily seduced into evil. . . . Those who sustain an illusion of invulnerability are the easiest touch for the con man, the cult recruiter or the social psychologist ready to demonstrate how easy it is to twist such arrogance into submission."