Philip George Zimbardo (born March 23, 1933) is a psychologist and a professor emeritus at Stanford University. He is president of the Heroic Imagination Project. He is known for his Stanford prison study and authorship of various introductory psychology books and textbooks for college students, including The Lucifer Effect and The Time Paradox.
I summarize more than 30 years of research on factors that can create a "perfect storm" which leads good people to engage in evil actions. This transformation of human character is what I call the "Lucifer Effect," named after God's favorite angel, Lucifer, who fell from grace and ultimately became Satan. Rather than providing a religious analysis, however, I offer a psychological account of how ordinary people sometimes turn evil and commit unspeakable acts. - In his introduction to his site on The Lucifer Effect (2007)