Zimbardo监狱实验

Psychology 242

Introduction

to Research

Dr. McKirnan, Class readings

Phillip Zimbardo.

A Pirandellian Prison.

New York Times Magazine, 4/8/73

The quiet of a summer morning in Palo Alto, California was shattered by a screeching squad

car siren as police swept through the city picking up college students in a surprise mass

arrest. Each suspect was charged with a felony, warned of his constitutional rights, spread-

eagled against the car, searched, handcuffed and carted off in the back seat of the squad

car to the police station for booking.

After fingerprinting and the preparation or identification forms for his

information file), each prisoner was left isolated in a detention cell to wonder what he had

done to get himself into this mess. After a while, he was blindfolded and transported to the

naked, skin-searched, deloused and issued a uniform, bedding, soap, and towel.

The warden offered an impromptu welcome:

probably know, I'm your warden. All of you have shown

that you are unable to function outside in the real world

for one reason or another - that somehow you lack the

responsibility of good citizens of this great country. We

of this prison, your correctional staff, are going to help

you learn what your responsibilities as citizens of this

country are. Here are the rules. Sometime in the near

future, there will be a copy of the rules posted in each of

the cells. We expect you to know them and to be able to

recite them by number. If you follow all of these rules

and keep your hands clean, repent for your misdeeds, and show a proper attitude of

penitence, you and I will get along just fine.

There followed a reading of the 16 basic rules of prisoner conduct.

Prisoners must remain silent during rest periods, after lights out, during meals and

whenever they are outside the prison yard. Two: Prisoners must eat at mealtimes and only

at mealtimes. Three: Prisoners must not move, tamper, deface or damage walls, ceilings,

windows, doors, or other prison property.... Seven: Prisoners must address each other by

their ID number only. Eight: Prisoners must address the guards as 'Mr. Correctional

Officer' ... Sixteen: Failure to obey any of the above rules may result in punishment.

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By late afternoon these youthful

barren cells trying to make sense of the events that had transformed their lives so

dramatically.

If the police arrests and processing were executed with customary detachment, however,

there were some things that didn't fit. For these men were now part of a very unusual kind of

prison, an experimental mock prison, created by social psychologists to study the effects of

imprisonment upon volunteer research subjects. When we planned our two week- long

simulation of prison life, we sought to understand more about the process by which people

called

called

managing the lives of their dependent charges.

Why didn't we pursue this research in a real prison? First, prison systems are fortresses of

secrecy, closed to impartial observation, and thereby immune to critical analysis from

anyone not already part of the correctional authority. Second, in any real prison, it is

impossible to separate what each individual brings into the prison from what the prison

brings out in each person.

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We populated our mock prison with a homogeneous group of people who could be

considered

participants (10 prisoners and 11 guards) were selected from more than 75 volunteers

recruited through ads in the city and campus newspapers. The applicants were mostly

college students from all over the US and Canada who happened to be in the Stanford area

during the summer and who were attracted by the $$15 a day for participating in a study of

prison life. We selected only those judged to be emotionally stable, physically healthy,

mature, law-abiding citizens. This sample of average, middle-class Caucasian college- age

males (plus one Asian student) was arbitrarily divided by the flip of a coin. Half were

randomly assigned to play the role of the guards, the others of the prisoners. There were no

measurable differences between the guards and the prisoners at the start of the experiment.

Although initially warned that as prisoners, their privacy and other civil rights would be

violated and that they might be subjected to harassment, every subject was completely

confident of his ability to endure whatever the prison had to offer for the full two-week

experimental period. Each subject unhesitatingly agreed to give his

participate.

The prison was constructed in the basement of Stanford University's psychology building,

which was deserted after the end of summer school. A long corridor was converted into the

prison

corridor were made into cells by installing metal barred doors and replacing existing

furniture with cots, three to a cell. Adjacent offices were refurbished as guards quarters,

interview-testing rooms and bedrooms for the

(Zimbardo). A concealed video camera and hidden microphones recorded much of the

activity and conversation of guards and prisoners. The physical environment was one in

which prisoners could always be observed by the staff, the only exception being when they

were secluded in solitary confinement (a small, dark storage closet, labeled

Our mock prison represented an attempt to simulate the psychological state of

imprisonment in certain ways. We based our experiment on an in- depth analysis of the

prison situation, developed after hundreds of hours of discussion with Carlo Prescott (our

ex-con consultant), parole officers and correctional personnel, and after reviewing much of

the existing literature on prisons and concentration camps.

frustrated, hopeless, anonymous, dehumanized

and emasculated. It was not possible,

pragmatically or ethically, to create such chronic

states in volunteer subjects who realize that they

are in an experiment for only a short time.

Racism, physical brutality, indefinite confinement

and enforced homosexuality were not features of

our mock prison. But we did try to reproduce

those elements of the prison experience that

seemed most fundamental.

We promoted anonymity by seeking to minimize

each prisoners sense of uniqueness and prior

identity. The prisoners wore smocks and nylon

stocking caps; they had to use their ID numbers;

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their personal effects were removed and they were housed in barren cells. All of this made

them appear similar to each other and indistinguishable to observers. Their smocks, which

were like dresses, were worn without undergarments, causing the prisoners to be restrained

in their physical actions and to move in ways that were more feminine than masculine. The

prisoners were forced to obtain permission from the guard for routine and simple activities

such as writing letters, smoking a cigarette or even going to the toilet; this elicited childlike

dependency from them.

Their quarters, though clean and neat, were small, stark and without esthetic appeal. The

lack of windows resulted in poor air circulation, and persistent odors arose from the

unwashed bodies of the prisoners. After 10 p.m. lockup, toilet privileges were denied, so

prisoners who had to relieve themselves would have to urinate and defecate in buckets

provided by guards. Sometimes guards refused permission to have them cleaned out, and

this made the prison smell.

Above all,

In our windowless prison, the prisoners often did not even know whether it was day or night.

A few hours after falling asleep, they were roused by shrill whistles for their

ostensible purpose of the count was to provide a public test of the prisoners knowledge of

the rules and of their ID numbers. But more importantly, the count, which occurred at least

once on each of the three different guard shifts, provided a regular occasion for the guards

to relate to the prisoners. Over the course of the study, the duration of the counts was

spontaneously increased by the guards from their initial perfunctory 10 minutes to a

seemingly interminable several hours. During these confrontations, guards who were bored

could find ways to amuse themselves, ridiculing recalcitrant prisoners, enforcing arbitrary

rules and openly exaggerating any dissension among the prisoners.

The guards were also

sunglasses that made eye contact with them impossible. Their symbols of power were billy

clubs, whistles, handcuffs and the keys to the cells and the main gate. Although our guards

received no formal training from us in how to be guards, for the most part they moved with

apparent ease into their roles. The media had already provided them with ample models of

prison guards to emulate.

Because we were as interested in guards' behavior as in the prisoners', they were given

considerable latitude to improvise and to develop strategies and tactics of prisoner

management. Our guards were told that they must maintain

that they were responsible for handling any trouble that might break out, and they were

cautioned about the seriousness and potential dangers of the situation that they were about

to enter. Surprisingly, in most prison systems,

psychological preparation or adequate training than this for what is one or the most complex,

demanding, and dangerous jobs our society has to offer. They are expected to learn how to

adjust to their new employment mostly from on-the-job experience, and from contacts with

the

manual for correctional officers at San Quentin,

Quentin is through experience and time. Some of us take more time and must go through

more experiences than others to accomplish this; some really never do get there.

You cannot be a prisoner if no one will be your guard, and you cannot be a prison guard if

no one takes you or your prison seriously. Therefore, over time a perverted symbiotic

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relationship developed. As the guards became more aggressive, prisoners became more

passive; assertion by the guards led to dependency in the prisoners; self-aggrandizement

was met with self-deprecation, authority with helplessness, and the counterpart of the

guards sense of mastery and control was the depression and hopelessness witnessed in

the prisoners. As these differences in behavior, mood, and perception became more evident

to all, the need for the now righteously powerful guards to rule the obviously inferior and

powerless inmates became a sufficient reason to support most any indignity of man against

man:

Guard K:

made and he grabbed me, screaming that he had just made it, and he wasn't going to let

me mess it up. He grabbed my throat, and although he was laughing I was pretty scared... I

lashed out with my stick and hit him in the chin (although not very hard) and when I freed

myself I became angry. I wanted to get back in the cell and have a go with him, since he

attacked me when I was not ready.

Guard M:

toilets out with their bare hands. I practically considered the prisoners cattle, and I kept

thinking

Guard A:

their bodies that filled the cells. I watched them tear at each other on orders given by us.

They didn't see it as an experiment. It was real and they were fighting to keep their identity.

But we were always there to show them who was boss.

Because the first day passed with out incident, we were surprised and totally unprepared for

the rebellion that broke out on the morning of the second day. The prisoners removed their

stocking caps, ripped off their numbers and barricaded themselves inside the cells by

putting their beds against the doors. What should

we do? The guards were very much upset

because the prisoners also began to taunt and

curse them to their faces. When the morning shift

of guards came on, they were upset at the night

shift who, they felt, must have been too permissive

and too lenient. The guards had to handle the

rebellion themselves, and what they did was

startling to behold.

At first they insisted that reinforcements be called

in. The two guards who were waiting on stand-by

call at home came in, and the night shift voluntarily

remained on duty without extra pay to bolster the

morning shift. The guards met and decided to treat

force with force. They got a fire extinguisher that

shot a stream of skin-chilling carbon dioxide and

forced the prisoners away from the doors; they

broke into each cell, stripped the prisoners naked,

took the beds out, forced the prisoners who were

the ringleaders into solitary confinement and

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generally began to harass and intimidate the prisoners.

p. 6 of 16

After crushing the riot, the guards decided to head off further unrest by creating a privileged

cell for those who were

the troublemakers into it and some of the good prisoners out into the other cells. The

prisoner ringleaders could not trust these new cellmates because they had not joined in the

riot and might even be

system. One of the leaders of the prisoner revolt later confided:

then, I think we could have taken over the place. But when I saw that the revolt wasn't

working, I decided to toe the line. Everyone settled into the same pattern. From then on, we

were really controlled by the guards.

It was after this episode that the guards really began to demonstrate their inventiveness in

the application of arbitrary power. They made the prisoners obey petty, meaningless, and

often inconsistent rules, forced them to engage in tedious, useless work, such as moving

cartons back and forth between closets and picking thorns out of their blankets for hours on

end. (The guards had previously dragged the blankets through thorny bushes to create this

disagreeable task.) Not only did the prisoners have to sing songs or laugh or refrain from

smiling on command; they were also encouraged to curse and vilify each other publicly

during some of the counts. They sounded off their numbers endlessly and were repeatedly

made to do pushups, on occasion with a guard stepping on them or a prisoner sitting on

them.

Slowly the prisoners became resigned to their fate and even behaved in ways that actually

helped to justify their dehumanizing treatment at the hands of the guards. Analysis of the

tape recorded private conversations between prisoners and of remarks made by them to

interviewers revealed that fully half could be classified as nonsupportive of other prisoners.

More dramatic, 85% of the evaluative statements by prisoners about their fellow prisoners

were uncomplimentary and deprecating.

This should be taken in the context of an even more surprising result. What do you imagine

the prisoners talked about when they were alone in their cells with each other, given a

temporary respite from the continual harassment and surveillance by the guards? Girl

friends, career plans, hobbies, or politics?

No, their concerns were almost exclusively riveted to prison topics. Their monitored

conversations revealed that only 10% of their talk was devoted to

per cent of the time they discussed escape plans, the awful food, grievances or ingratiation

tactics to use with specific guards in order to get a cigarette, permission to go to the toilet or

some other favor. Their obsession with these immediate survival concerns made talk about

the past and future an idle luxury.

And this was not a minor point. So long as the prisoners did not get to know each other as

people, they only extended the oppressiveness and reality of their life as prisoners. For the

most part, each prisoner observed his fellow prisoners allowing the guards to humiliate them,

acting like compliant sheep, carrying out mindless orders with total obedience and even

being cursed by fellow prisoners (at a guard's command). Under such circumstances, how

could a prisoner have respect for his fellows, or any self-respect for what he obviously was

becoming in the eyes of all those evaluating him?

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The combination of realism and symbolism in this

experiment had fused to create a vivid illusion of

imprisonment. The illusion merged inextricably

with reality for at least some of the time for every

individual in the experiment. It was remarkable

how readily we all slipped into our roles,

temporarily gave up our identities and allowed

these assigned roles and the social forces in the

situation to guide, shape and eventually to control

our freedom of thought and action.

But precisely where does one's

one's

public role behavior clash, what direction will

attempts to impose consistency take? Consider

the reactions of the parents, relatives and friends

of the prisoners who visited their forlorn sons,

brothers and lovers during two scheduled visitors'

hours. They were taught in short order that they

were our guests, allowed the privilege of visiting

only by complying with the regulations of the

institution. They had to register, were made to

wait half an hour, were told that only two visitors

could see any one prisoner, the total visiting time

was cut from an hour to only 10 minutes, they

had to be under the surveillance of a guard, and

before any parents could enter the visiting area,

they had to discuss their son's case with the

warden. Of course they complained about these

arbitrary rules, but their conditioned, middle-class

reaction was to work within the system to appeal

privately to the superintendent to make conditions

better for their prisoners.

In less than 36 hours, we were forced to release prisoner 8612 because of extreme

depression, disorganized thinking, uncontrollable crying and fits of rage. We did so

reluctantly because we believed he was trying to con us - it was unimaginable that a

volunteer prisoner in a mock prison could legitimately be suffering and disturbed to that

extent. But then on each of the next three days another prisoner reacted with similar anxiety

symptoms, and we were forced to terminate them, too. In a fifth case, a prisoner was

released after developing a psychosomatic rash over his entire body triggered by rejection

of his parole appeal by the mock parole board. These men were simply unable to make an

adequate adjustment to prison life. Those who endured the prison experience to the end

could be distinguished from those who broke down and were released early in only one

dimension - authoritarianism. On a psychological test designed to reveal a person's

authoritarianism, those prisoners who had the highest scores were best able to function in

this authoritarian prison environment.

If the authoritarian situation became a serious matter for the prisoners, it became even more

serious and sinister - for the guards. Typically, the guards insulted the prisoners, threatened

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them, were physically aggressive, used instruments (night sticks, fire extinguishers, etc.) to

keep the prisoners in line and referred to them in impersonal anonymous, deprecating ways:

significant increase in the use of most of these domineering, abusive tactics.

Everyone and everything in the prison was defined by power. To be a guard who did not

take advantage of this institutionally sanctioned use of power was to appear

it,

appropriate guard behavior. Using Erich Fromm's definition of sadism, as

absolute control over another living being,

during this study behaved sadistically toward the prisoners. Many of them reported - in their

diaries, on critical-incident report forms and during post- experimental interviews - being

delighted in the new-found power and control they exercised and sorry to see it relinquished

a the end of the study.

Some of the guards reacted to the situation in the extreme and behaved with great hostility

and cruelty in the forms of degradation they invented for the prisoners. But others were

kinder, they occasionally did little favors for the prisoners, were reluctant to punish them,

and avoided situations were prisoners were being harassed. The torment experienced by

one of these good guards is obvious in his perceptive analysis of what it felt like to be

responded to as a guard:

that we were continually called upon to act in a way that just was contrary to what I really

feel inside. I don't feel like I'm the type of person that would be a guard, just constantly

giving out ... and forcing people to do things, and pushing and lying - it just didn't seem like

me and to continually keep up and put on a face like that is just really one of the most

oppressive things you can do. It's almost like a prison that you create yourself - you get into

it, and it becomes almost the definition you make of yourself, it almost becomes like walls,

and you want to break out and you want just to be able to tell everyone that

me at all, and I'm not the person that's confined in there - I'm a person who wants to get out

and show you that I am free, and I do have my own will, and I'm not the sadistic type of

person that enjoys this kind of thing.

Still the behavior of these good guards seemed more motivated by a desire to be liked by

everyone in the system than by a concern for the inmates' welfare. No guard ever

intervened in any direct way on behalf of a prisoner, ever interfered with the orders of the

cruelest guards or ever openly complained about the subhuman quality of life that

characterized this prison.

Perhaps the most devastating impact of the more hostile guards was their creation of a

capricious, arbitrary environment. Over time the prisoners began to react passively. When

our mock prisoners asked questions, they got answers about half the time, but the rest of

the time they were insulted and punished - an it was not possible for them to predict which

would be the outcome. As they began to toe the line, they stopped resisting, questioning,

and indeed, almost ceased responding altogether. There was a general decrease in all

categories of response as they learned that the safest strategy to use in an unpredictable,

threatening environment from which there is no physical escape - do nothing, except what is

required. Act not, want not, feel not and you will not get into trouble in prison-like situations.