Stanley Milgram conducted an
experiment on "Obedience to Authority" in which
volunteers were given the
role of a
teacher. As the teacher they were
instructed to ask
a series of questions to a "learner". Every time the "learner"
got an answer wrong, they pressed
the next in a series of
buttons. Each button, they were told, administered a higher and
higher voltage of
electric shock to the learner. They were told that the shocks would
hurt, and could even
kill the learner. The learner was, infact, an
actor,
pretending that they were receiving the
shocks.
Milgram's experiment was to see how far the volunteer would go.
Over 90% of the volunteers in the teacher role continued up the scale of buttons, until 450 volts, no matter how much the learner screamed, and begged for the experiment to be stopped.
Milgram concluded that obedience to authority is a "danger to survival inherent in our make-up", and that our conscious mind would prefer we inflict harm upon others, than be disobedient to an authority figure.
Paraphrased from an article on Obedience found at: http://www.mind-trek.com/reports/misc/obedienc.htm