Stanford Psychologist Dies

Philip Zimbardo, an influential psychologist best known for carrying out the "Stanford Prison Experiment," died last week at the age of 91, the university announced Friday. His six-decade career also spanned research in subjects ranging from persuasion to cults and hypnosis. 

Interested in how situational power affected behavior, Zimbardo designed the 1971 Stanford experiment to simulate a prison environment in the basement of the school's psychology department, with students assigned the roles of either guards or prisoners. The guards—given wide latitude over prisoners with little oversight or repercussions—reportedly began behaving abusively so quickly the experiment was ended six days into the two-week study. Zimbardo argued the results showed situations influence behavior more than commonly appreciated. 

The experiment was later criticized over ethical and methodological concerns, with participant interviews later suggesting some had acted in a manner they thought Zimbardo wanted. The study has never been replicated in a rigorous fashion, leaving the results in question. Learn more about broader replication concerns here.