Social Roles: Philip Zimbardo's Prison Experiment

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  • 0:07 Philip Zimbardo
  • 0:54 Stanford Prison Experiment
  • 2:08 Ethical Fallout
  • 2:57 Impact on Psychology
  • 4:02 Lesson Summary
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Lesson Transcript
Instructor: Natalie Boyd

Natalie is a teacher and holds an MA in English Education and is in progress on her PhD in psychology.

Philip Zimbardo ran a notorious experiment, simulating a prison scenario in the basement of a Stanford University building. As a result of the experiment, psychologists learned how situations affect behavior and the importance of ethics in psychology.

Philip Zimbardo

Imagine for a moment that you are in prison. You are given a list of rules to follow, and if you don't follow them, the guards come up with horrible punishments for you, like making you clean toilets with your bare hands. Would you obey the rules, or would you rebel?

Now take a moment and imagine that you are in charge of running a prison. You're told that you must keep the prisoners in line, but you cannot use physical violence, and you don't have any weapons. How would you keep order?

This is a situation that many college students found themselves in during a notorious experiment run by Philip Zimbardo. He was interested in how social roles affect the behaviors of people - that is, how the part people play affects the way they act. What he found was much, much more than that.

The Stanford Prison Experiment

Zimbardo was a professor at Stanford University in 1971, and he advertised for young men to be part of a two-week experiment.

The 24 men who were selected for the experiment were randomly assigned to be either prisoners or guards. They were then sent into the basement of a building at Stanford University to stay for two weeks, while Zimbardo and the researchers monitored them through a video feed.

The guards came up with a list of rules for the prisoners to obey: things like when they could eat and that they could only be called by their prisoner numbers instead of their names. The guards were told that they could not physically harm the prisoners, but that they could scare them.

On the second day, some of the prisoners refused to obey the guards. In retaliation, the guards began to punish the prisoners. But as time went on, the guards' punishment began to get more and more brutal. They deprived the prisoners of sleep and forced them into degrading situations. They made the prisoners clean toilets with their bare hands.

The prisoners began to show signs of trauma, including severe depression and anxiety. Several of them cried and acted as though they were close to a nervous breakdown. The researchers had to let several prisoners go early because they were so traumatized.

Ethical Fallout

Despite the escalating punishments and the emotional issues displayed by the prisoners, Zimbardo and his colleagues did not discuss stopping the experiment until Zimbardo's then-girlfriend, a graduate student at Stanford, visited the faux prison and saw what was going on. She was horrified and told Zimbardo that he should stop the experiment. Realizing that she was right, Zimbardo pulled the plug on the experiment after six days - a week earlier than originally planned.

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