In the summer of 1961, at Yale University, ordinary residents of New Haven — teachers, salesmen, engineers, labourers — answered a newspaper advertisement offering a small fee to take part in a study of memory and learning. What they actually walked into was one of the most disturbing experiments psychology has ever run, designed by a twenty-eight-year-old assistant professor named Stanley Milgram to answer a question the world was asking with new urgency. Weeks earlier, the Nazi administrator Adolf Eichmann had gone on trial in Jerusalem, defending his role in the Holocaust with the claim that he had only been following orders. Milgram wanted to know how far ordinary people would go when an authority told them to do something monstrous.
The switches on the machine
Each volunteer was assigned the role of "teacher" by a rigged drawing of lots. The "learner," strapped to a chair in an adjoining room with an electrode on his arm, was in fact an actor, a mild-mannered accomplice. The teacher was told to read out word pairs and, every time the learner got one wrong, to administer an electric shock — and to increase the voltage with each mistake. Before them sat an imposing shock generator with a row of switches labelled from a mild 15 volts up to a terrifying 450, with printed warnings escalating from "Slight Shock" through "Danger: Severe Shock" to a final, ominous "XXX."
No real shocks were delivered, but the teacher did not know that. As the voltage climbed, the learner — following a script played on a recording — began to protest, then to cry out in pain, to bang on the wall, to complain of a heart condition, and finally to fall horribly silent, as if unconscious or worse. Whenever the teacher hesitated, a calm experimenter in a grey lab coat delivered a sequence of scripted prods: "Please continue." "The experiment requires that you continue." "It is absolutely essential that you continue." "You have no other choice, you must go on."
Sixty-five per cent
Before running the study, Milgram asked psychiatrists and students to predict the results. They guessed that almost no one would go to the end — that only a pathological fraction, perhaps one in a thousand, would deliver the maximum shock. The reality stunned everyone. In the best-known version of the experiment, about sixty-five per cent of ordinary participants continued all the way to 450 volts, administering what they believed were dangerous, possibly lethal shocks to a screaming stranger, simply because a man in a lab coat told them to.
They did not do it happily. Milgram's films show people sweating, trembling, laughing in distress, begging to stop, insisting the experiment be checked on the victim — and then, prodded by the quiet authority beside them, flipping the next switch anyway. The lesson Milgram drew was bleak: the capacity for obedience to authority runs so deep in ordinary, decent people that, in the right situation, most of us can be led to inflict grave harm. Evil, he suggested, does not require monsters; it requires a hierarchy and a willingness to hand over responsibility to the person giving orders.
Milgram published the first results in 1963 and expanded them in his 1974 book, Obedience to Authority. The findings became some of the most cited and most argued-over in all of social science. They also provoked a storm about the ethics of the research itself. Participants had been deliberately deceived and put through genuine anguish, sweating and shaking under the belief they were torturing a man. Though Milgram surveyed them afterwards and reported that most were glad to have taken part, critics charged that the psychological cost to the subjects was too high. The controversy helped drive the creation of the strict ethical review boards that now govern experiments on human beings — which is one reason the study, in its original form, could probably never be run today.
Later scholars have questioned aspects of it: how faithfully the experimenters stuck to the script, how the results were reported, and whether "obedience" is even the right word for what the subjects felt. But the core finding has been echoed in variations across countries and decades, and it endures as a mirror few of us like to look into. Milgram's shock generator was never plugged into the learner. It was, in effect, plugged into the rest of us — and it measured how readily we obey.
Quiz nuggets
- Stanley Milgram ran his obedience experiments at Yale University starting in 1961, partly inspired by the trial of Adolf Eichmann.
- Participants (the "teachers") were ordered to give what they believed were escalating electric shocks up to 450 volts to a "learner," who was really an actor.
- About 65 per cent of subjects obeyed all the way to the maximum shock, far more than experts had predicted.
- The experimenter used scripted prods such as "The experiment requires that you continue."
- Milgram published the work in 1963 and the book Obedience to Authority in 1974; the study fuelled major reforms in research ethics.