Similar to The Milgram experiment, the Stanford prison experiment uncovers the "monster" that hides deep within our psychology, ready to be unleashed if permitted by the situations.
The Stanford prison experiment was a psychological experiment that was conducted at the Stanford University in 1971, from August 14 to August 20. Responsible for the experiment was a team of researchers led by psychology professor Philip Zimbardo, funded by the US Office of Naval Research. The purpose of the experiment was to reveal the causes of conflicts in prisons between the military guards and the prisoners.
According to the experiment's scenario, nine people were chosen to play the role of the prisoners and another nine people would play the role of the guards, in a temporary prison scene built in the basement of the University. There were also 6 alternates (3 guards and 3 prisoners). Zimbardo took on the role of the superintendent, and an undergraduate research assistant the role of the prison warden. The experiment was designed in a way to induce disorientation, depersonalization and deindividualization in the participants.
Before starting the experiment, the researchers had a conversation with the guards. They explained them that they should not physically harm the prisoners. Nevertheless, during this session, Zimbardo can be seen in the footage of the study telling to the guards:
You can create in the prisoners feelings of boredom, a sense of fear to some degree, you can create a notion of arbitrariness that their life is totally controlled by us, by the system, you, me, and they'll have no privacy... We're going to take away their individuality in various ways. In general what all this leads to is a sense of powerlessness. That is, in this situation we'll have all the power and they'll have none
When the experiment began, the guards were provided full prison guard outfit including wooden batons (to establish their status) and mirrored glasses to avoid eye contact. The local Palo Alto police department assisted Zimbardo to arrest the prisoners in their homes with full booking procedures, including fingerprinting and taking mug shots, charged for armed robbery. They were then taken into the small cells, each one designed to fit 3 prisoners, with uncomfortable ill-fitting smocks and stocking caps, as well as a chain around one ankle. The guards were instructed to call prisoners by their assigned numbers sewn on their uniforms thereafter.
The first problems began before the end of day two. The prisoners of cell 1 blocked their cell door with their beds and took of their stocking caps, refusing to follow the instructions of the guards. Then, guards from other shifts volunteered to work overtime as an assist. As a result, the guards attacked the prisoners with fire extinguishers. One of the guards then suggested to use psychological tactics as means of control. It first began with the "privilege cell". Whoever managed to enter this cell had extra privileges against the other prisoners, such as better meals. But the privileged prisoners refused it to match their fellow prisoners.
Within 36 hours, one of the prisoners began to act like crazy. Zimbardo said:
#8612 then began to act crazy, to scream, to curse, to go into a rage that seemed out of control. It took quite a while before we became convinced that he was really suffering and that we had to release him.
Guards soon began to use the assigned numbers of the prisoners as a harass. Prisoners were forced to call their numbers - refusing to do so or calling a wrong number lead to physical punishment such as protracted exercise. Things went worse when the guards forced some prisoners to urinate and defecate in buckets which were left in their cells in purpose. They also removed some mattresses from the cells leaving the prisoners sleeping on concrete. Some prisoners were forced to be naked as well. Several guards became increasingly cruel as the experiment continued; experimenters reported that approximately one-third of the guards exhibited genuine sadistic tendencies. The peak of sadism was when one of the prisoners was punished for not eating his sausages due to a hunger strike that he had began. Prisoner #416 was a replacement prisoner for prisoner #8612 who left. He was put in a dark closet for "solitary confinement". The guards said that they would let $416 out of the closet only if all the prisoners would give their blankets, but the prisoners refused to do so. They were also instructed to repeatedly punch the door of the closet while shouting.
The end of the experiment
The experiment was programmed to run for 14 days (two weeks). During the 6th day, a graduate student in psychology named Christina Maslach visited the prison to observe the experiment. Among other observers, Maslach was the only one who questioned the morality of this experiment. Then, Zimbardo aborted the experiment. It should be mentioned that Zimbardo was dating Maslach and later he married her...
The conclusions of the experiment
It was obvious from the experiment that it was not the individual personalities of the participants but rather the specific situation that lead their acts. These results are perfectly compatible from the results of the Milgram experiment, in which ordinary people carried out "orders" to administer agonizing pain and probably death using electric shocks as means of punishment (read here)