► What happens when you put good people in
an evil place?
► Does humanity win over evil, or does evil
► These are some of the questions posed in
this dramatic simulation of prison life
conducted in the summer of 1971 at
► Social psychologist
► Experiment to study
the behaviors of
people without criminal
records in a mock
► Selected 24 healthy
young men volunteers
► Normal, intelligent,
middle class college
► Half were assigned the
roles of guards; the
other half were
Guards made their rules
unexpectedly picked up
from their homes,
handcuffed and searched
Then stripped, deloused,
groin uniforms, and put in
The experiment was
supposed to last two
But the experiment was
stopped after only six
Each group could no
longer distinguish between
their roles and real life
In only a few days, the
guards became sadistic
and the prisoners became
depressed and showed
signs of extreme stress.
► Psychology Professor Philip Zimbardo's Stanford
Prison Experiment of August 1971 quickly became
► Using realistic methods, Zimbardo and others
were able to create a prison atmosphere that
transformed its participants.
► The young men who played prisoners and guards
revealed how much circumstances can distort
individual personalities -- and how anyone, when
given complete control over others, can act like a
Let’s see what happened . . .
► "It shows how easy it is for good people to
become perpetrators of evil."
► Zimbardo maintains that the student-participants
suffered no long-term harm -- even though some
had symptoms of mental breakdown during the
experiment. But now, the standards for using
human subjects in research wouldn't permit such
► "Because of the rules, it's unlikely to ever be
► Zimbardo has strong opinions on the
harmful effects of harsh prison sentences.
"Prisons are evil places that demean
humanity. ... They are as bad for the guards
as they are for the prisoners," he said,
pointing to results of his experiment
showing that both guards' and prisoners'
personalities were warped by their given
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