Philip Zimbardo GRD ’59 was the lead investigator in the Stanford prison experiment, which was conducted 40 years ago this summer. The News spoke with him by phone Friday about the study, the public reaction and his Yale ties.

Q: Tell us a little about your psychology education.

A: I did my Ph.D. at Yale from 1954-’59 and got my master’s degree in ’55. I actually was the first graduate student to teach his own course — I taught “Intro Psych” for two years — unlike Harvard at that time, where they didn’t have graduate students teaching. But I took a course on how to teach psych, and at the last minute one of the professors couldn’t teach, so I actually taught for two years. The terrible thing was my class was Tuesday, Thursday and Saturday at 8 a.m. during football season, and those were the days they took attendance. But I loved it.

Q: What was the reaction to your and Milgram’s studies?

A: There was backlash to [Milgram’s] study: People wrote articles in professional journals saying “This is wrong, people shouldn’t be allowed to study like this.” Nobody was hurt, but people still felt guilty.

In the Stanford prison experiment, people were actually hurt. In my study, the prisoners were there 24/7, guards worked eight-hour shifts, so it was a totally different phenomenon. My study is about the power of institutions, where nobody tells you to do bad things, but where the institution has certain norms and group dynamics. It’s a more general, vague set of influences on behaviors. [Milgram’s] was about when authority tells you to do something.

Q: Do you think the Stanford prison experiment was ethical?

A: The point is what the difference is between what you know and can predict before and what you can see afterwards. [The ethical committee] approved kids playing cops and robbers in a basement, of course they’d approve it. We never imagined it would be so realistic.