Four decades ago Stanford psychologist Philip Zimbardo created the now-famous prison experiment.
Zimbardo divided a group of college students into prisoners and prison guards and consigned them to a dungeon in the basement of the Stanford psychology department.
Wikipedia described the terms of the experiment:
The volunteers knew they were being used in a study but they did not know when the study would be taking place, so the initial shock of being randomly arrested one morning and taken to the mock prison put them in a mild state of shock. On arrival, the "prisoners" were stripped, searched, shaved and deloused, which caused a great deal of humiliation. They were then issued uniforms, ID numbers, and escorted to their cells by the volunteer prison guards. These changes isolated the prisoners making it harder for them to portray their individual characteristics. The guards themselves were not given any specific instruction or guidelines for the way they were to treat the prisoners. Instead, the psychologists allowed them to do whatever was needed to keep order in the prison. They were dressed very professionally in identical uniforms. They also wore a whistle around their neck and carried a night stick.
After a short period of time the situation turned chaotic and violent. Wikpedia explains why the experiment was aborted:
The planned two-week study into the psychology of prison life ended after only six days due to emotional trauma being experienced by the participants. The students quickly began acting out their roles, with "guards" becoming sadistic and "prisoners" showing extreme passivity and depression.
From the study Zimbardo concluded that human beings are not intrinsically good or evil, but that everyone has the capacity to do both. In his view the experiment proved that situations can render people good or evil.
In his words:
Good people can be induced, seduced, and initiated into behaving in evil ways. They can also be led to act in irrational, stupid, self-destructive, antisocial, and mindless ways when they are immersed in 'total situations' that impact human nature in ways that challenge our sense of the stability and consistency of individual personality, of character, and of morality.
Surely, all individuals have the capacity to do good or to do ill. If such had not been the case there would be no morality. Yet, one needs to pause here and to ask a few questions.
The students who were participating in the experiment were play-acting. They knew they were play-acting. Why do we believe that behavior elicited in artificial circumstances tells us anything about how these same persons would or would not act in their real lives?
I have no doubt but that some people are incapable of committing evil acts under any circumstance. And I also have no doubt but that some people are irredeemably evil.
The experiment does not address such questions. It seems to suggest that any human being, submitted to sufficient stress can be induced to act as though he were evil. Again, does this prove that people are intrinsically evil or that we can elicit uncharacteristic behaviors by forcing people into unreal situations?
Obviously, the experiment does not really replicate the conditions of a real prison. It casts adolescents in the roles of prison guards and prison inmates and invites them to conduct some improvisational theatre.
Beyond the fact that these students are pretending, they are also untrained in the art of theatrical improvisation.
In a real prison the guards have been trained. They have applied for their jobs and have received proper orientation. They have learned the rules and routines of the job. Their actions and the meaning of their actions are determined by a strictly defined social structure. They are not told to fend for themselves in a situation where there are, effectively, no rules.
Of course, the student volunteers were subjected to the kinds of humiliation that real prisoners receive. And yet, there was a significant difference: real prisoners know why they are in prison. They know that they are being punished for their misdeeds. What would count as an arbitrary and unjust humiliation for a college student would be meaningful for a convicted criminal.
Why did the students behave as they did?
Since they were not real prison guards and did not have a script to follow, they improvised, basing their behavior on what they knew through the media, of prison conditions. They were playing roles and they wanted to play them well. Being untrained in the craft of acting, they had far more difficulty maintaining the distance between their appointed roles and themselves.
The “guards” became abusive, not so much because in the experiment had brought out something basic to them, but because they wanted to be good students, and wanted to be good at acting out their roles.
This raises an important psychological question. When an actor plays a role in a movie or on stage, he will feel an emotion that is appropriate to his character: perhaps anger or jealousy. In his performance he will express the appropriate emotion as he recites lines and performs actions.
But, if an actor plays Othello and suffers feelings of jealousy about Desdemona have we demonstrated anything more than his capacity to express the emotion of jealousy? If the same actor, in the course of the play, pretends to murder Desdemona and does so convincingly, ought we to assume that he has gotten in touch with his inner homicidal maniac? Ought the actor’s wife take out an order of protection?
When an actor is in character, he will feel emotion. Are those emotions his own? Do they say something about him, about what he is capable of doing in real life, or does it show us what he can adopt to play a role?
Up to a point, I agree with Zimbardo that we are all capable of good and evil. But his experiment does not really show what we are capable of. It shows what we are capable of pretending.
The students based their behavior on their sense of what is expected of them and on their media-driven knowledge of prison conditions.
Generalizing about human behavior or the human soul from such artificial circumstances strikes me as unpersuasive.