Under the Microscope / Prof William Reville: We have all seen films and read books in which, after the war, Nazi soldiers excused their terrible actions on the basis that they had merely been following orders. Most of us like to feel that if we found ourselves in similar circumstances we would behave differently to the Nazis. Unfortunately the evidence we have tells us most of us would follow orders to do terrible things just as the Nazis did.
In 1961, Stanley Milgram, professor of social psychology at Yale University, carried out a landmark study in this area. He later wrote a book Obedience to Authority: An Experimental View (Harper Collins, 1974) describing the work and its implications. The study was designed to measure participants' willingness to obey an authority who instructs them to take actions that conflict with their conscience. The year of the study, 1961, was the year after the trial of Adolf Eichmann.
The participants in Milgram's experiment were men, aged 20-50, who came from a wide range of educational backgrounds. They were recruited by newspaper ads and direct mail, and were told that the experiment would take one hour and they would be paid $4.50. The participants were told that the experiment would test the effects of punishment on learning behaviour.
Unknown to the participants the experimenter had hired aaccomplice who was an actor. When a participant arrived he would find the experimenter with another "participant" (the actor). The two participants were "randomly" allocated the roles of learner and teacher when the experimenter handed each a slip of paper. Unknown to the genuine participant, each slip said "teacher". The teacher and learner now went into separate rooms, so that they could communicate with - but not see - each other. The accomplice always mentioned he had a weak heart.
The learner was seated in a chair with his arms strapped in and an electrode strapped to his wrist. He was told he was to learn a list of word pairs and that whenever he made a mistake the teacher would give him an electric shock of increasing intensity. The teacher watched this and then was taken to his room to be seated before a shock generator, which had a line of shock switches ranging from 15 to 450 volts in 15-volt steps. Verbal signs describe the severity of the shocks from "Slight" to "Danger - Severe Shock".
The teacher was given a list of word pairs to teach the learner. He read the list to the learner and then read the first of each word pair and four possible answers. The learner made his choice by pressing a button. If the response was wrong, the teacher administered a shock, increasing by 15 volts with each wrong answer. If the response was correct, the teacher would go on to the next word pair.
The teacher believed he was administering painful shocks, but in reality no shocks were being delivered. The accomplice started a tape of pre-recorded responses to each shock level that is connected to the shock-generator. After a few shock increases the actor started to bang on the wall and shout. He complained about his weak heart and asked for the teacher to stop the experiment. As the voltage continued to increase, the shouting turned to screams and, finally, the highest voltage elicit no sound from the learner - just ominous silence.
At a shock level of 135 volts, many teachers asked the experimenter to stop the experiment and check on the learner, but many continued after the experimenter told them they would not be held responsible. Each time the teacher said he would like to stop the experiment, the experimenter gave successive verbal instructions - "please continue", "the experiment requires you to continue", "it is essential that you continue", "continue, you have no choice". The experiment was stopped if the teacher still wished to stop after receiving these four verbal instructions. Otherwise the experiment ended after the top voltage of 450 volts was administered three times in succession.
Before doing his experiment Milgram conducted a poll of psychologists and asked them to predict the results. They all said they expected that the maximum voltage would only be inflicted by a few sadists. However, Milgram found that 65 per cent of teachers administered the 450-volt shock. The experiment has been repeated many times in many places and with many variations. All of the experiments have produced similar results. For example, the results are largely the same when women are employed in the experiment in place of men.
Milgram's results are surprising and very disturbing. He summarised himself in a 1974 article in Harper's Magazine: "The legal and philosophic aspects of obedience are of enormous import, but they say very little about how people behave in concrete situations. I set up a simple experiment at Yale University to test how much pain an ordinary citizen would inflict on another person simply because he was ordered to by an experimental scientist. Stark authority was pitted against the subjects' strongest moral imperatives against hurting others, and, with the subjects' ears ringing with the screams of the victims, authority won more often than not. The extreme willingness of adults to go to almost any lengths on the command of an authority constitutes the chief finding of the study and the fact most urgently demanding explanation."
Why relatively few people have insufficient personal resources to resist authority when it asks them to do something that infringes fundamental moral standards is a question worth considering in a future article.
William Reville is associate professor of biochemistry and public awareness of science officer at UCC - http://understandingscience.ucc.ie