The Stanford Prison Experiment

03.11.2018 |

Episode #1 of the course Most brilliant social psychology experiments by John Robin


Welcome to a ten-day journey through some of the most brilliant social psychology experiments.

My name is John Robin. I’m an author and entrepreneur, and I’ve also written several Highbrow courses on writing and math, including the most recent “Brain-Twisting Paradoxes,” another exciting course I highly recommend once you have completed this one. I enjoy using my skill as an author to teach others about interesting topics, and now it’s time to enter a new one.


What Happens When You Put Good People in an Evil Place?

This scenario is exactly what was played out in the famous Stanford Prison experiment, conducted at Stanford University in 1971, led by psychology professor Philip Zimbardo. The participants were college students.

Zimbardo was careful in his selection. Those with criminal backgrounds were not allowed to participate nor those with known mental health impairments. He used the basement of Stanford’s psychology department building, converted it to a makeshift prison, and selected 24 participants, 12 of whom were to be prisoners and 12 of whom would be guards. The experiment was to run for two weeks.

Everything was observed on closed-circuit cameras. Each cell contained only a small cot, housing three prisoners, while the guards lived somewhere separate from the “prison,” where they could relax and indulge however they wanted.

Guards worked in eight-hour shifts in teams of three and were instructed to not harm the prisoners physically and to provide them with food. They were equipped with wood batons and wore prison guard uniforms, while the prisoners wore uncomfortable smocks that fit poorly. To induce the psychological effects of depersonalization and deindividualization that Zimbardo wanted to create, guards were to refer to the prisoners by their prisoner ID number, sewn on each prisoner’s uniforms.

He even took this to another level to ensure the disorientation of incarceration was simulated:

All prisoners were “arrested” by local police (also participating in the experiment) at their homes, where they were charged with “armed robbery,” thus beginning their prison term with public humiliation. They were then transported to the prison, where they were strip-searched and given their prisoner identities.

Zimbardo’s goal was to observe the psychological effects on those who were prisoners and those who were guards, to gather information outside the context of those who were actually living those roles (i.e., lawbreakers who were incarcerated and employed guards who were looking after prisoners). His big question: Would the roles themselves lead to the commonly perceived anti-social and repulsive behavior we see in the prison system? Where guards abuse their authority? Where inmates band together and sometimes incite riots or inflict violence on each other?

The experiment lasted only six days. Despite being paid $15/day, several volunteers left, and eventually, it was abandoned.

In fact, it was only after Day 1 that Cell 1 blockaded the door. After only 36 hours, one prisoner started to scream, curse, and go into a rage. He was soon released.

Sanitary conditions declined. Some prisoners urinated or defecated anywhere except the sanitary bucket placed in their cell. This led some guards to punish prisoners by refusing to replace sanitary buckets or sometimes, to remove the mattresses from the cots. In fact, as the experiment progressed, the study noted about 1/3 of the guards exhibited sadistic tendencies toward the prisoners.

There were hunger strikes, and some prisoners even started to internalize their roles, at one point saying that they would rather get “parole” than earn their $15/day. One prisoner who refused to eat his sausages was placed in “solitary confinement,” which meant being confined to a closet while guards pounded the door and shouted at him.


The Power of Authority

Zimbardo’s experiment, though still controversial to some theorists, demonstrates the psychological power of authority at play in prison settings. In fact, it has altered how US prisons are run, an example being how juveniles are now removed from adult populations due to perceived risk of violence to them from the more authoritative adult inmates.

Tomorrow, we’ll move onto another popular experiment, this one about a special kind of blindness that affects us all.


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Recommended film

There actually was a movie made about this experiment in 2015. Watch the trailer here.


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