Professor Philip Zimbardo visits CSUMB to explain.

Famed Stanford psychology professor Philip Zimbardo has ventured into the darkest corners of the human mind, studying history’s most audacious evildoers (Adolf Hitler, the Ku Klux Klan) and arranging arguably the most infamous psychology experiment in history, the 1971 Stanford Prisoner Experiment (SPE). He understands why evil happens. He knows who is capable of evil. And he knows that this information often shocks people.

On Tuesday, Sept. 25, Zimbardo will discuss his new book, The Lucifer Effect: Understanding How Good People Turn Evil, at CSUMB.

“Each of us has this illusion of invulnerability – ‘Bad things don’t happen to me,’ ” Zimbardo says. “We all think we are above average. Statistically we can’t be.”

That’s the part that stuns people, he says: that everyone can behave horribly when placed in the right (or more accurately, wrong) context.

He saw striking data of this in ’71, when he hired 23 volunteers to spend two weeks in a mock prison in a campus basement. The men were randomly divided into “prisoners” and guards” and instructed to act as they believed prisoners and guards would behave. On day two, the prisoners rebelled.

“The guards came to me: ‘What do we do?’ ” Zimbardo told the New York Times. “ ‘It’s your prison,’ I said, warning them against physical violence. The guards then quickly moved to psychological punishment, though there was physical abuse, too.” Guards denied food, water and sleep, sprayed the inmates with fire extinguishers, stripped them and dragged them through the yard. Zimbardo cancelled the experiment after five days.

He saw more data surface recently from Abu Ghraib. Ultimately, he testified in defense of Sgt. Chip Frederick, who was later sentenced to eight years, contending that Frederick was just like the “nice young men in SPE” – given vague orders in a highly distressed situation. The abuses that took place, he argued, were not the work of a few “bad apples,” but what he calls “bad barrels.”

Zimbardo Speaks At 7pm In The World Theatre, 100 Campus Center, Csumb, On Sept. 25. Free. 582-4187.