In the early 1960s, a deceptively simple question took shape inside a laboratory at Yale University: how far would an ordinary person go if instructed by an authority figure to harm someone else? The answer, offered by psychologist Stanley Milgram, would become one of the most cited, and most contested, findings in modern psychology.Milgram’s obedience experiments, conducted between 1961 and 1962, did not begin as abstract inquiry. They were shaped by the aftermath of the Holocaust and, more specifically, by the trial of Adolf Eichmann, who defended his role in organising the logistics of the mass deportation of Jews to ghettos and extermination camps, a central part of the Nazi programme of systematic mass murder, by claiming he had been “just following orders.” In his 1974 book Obedience to Authority, Stanley Milgram framed the question directly: “Could it be that Eichmann and his million accomplices in the Holocaust were just following orders? Could we call them all accomplices?”
How the experiment was designed
Milgram recruited participants through newspaper advertisements, presenting the study as research on learning and memory. In the most widely cited version, 40 men took part, each paid $4.50. Participants were assigned the role of “teacher.” Another individual, introduced as a fellow participant but in fact an actor working with the researchers, played the “learner.” The learner was placed in a separate room and connected to what appeared to be an electrical shock device. The teacher sat in front of a shock generator marked from 15 volts up to 450 volts, increasing in 15-volt increments. The switches were labelled in escalating terms: “slight shock,” “moderate shock,” and “danger: severe shock,” with the final switches marked simply “XXX.” The task was structured but repetitive. The teacher read out word pairs and tested the learner’s memory. Each incorrect answer required a shock, with the voltage increasing each time. The shocks were not real. The participants did not know that. As the session progressed, the learner’s responses were scripted. At lower levels, he expressed mild discomfort. As the voltage increased, his reactions became more urgent, he complained of a heart condition, demanded to be released, and at 300 volts began pounding on the wall. After that, he fell silent. The experimenter instructed that silence should be treated as a wrong answer. When participants hesitated, they were given a standardised sequence of prompts: “Please continue.” “The experiment requires that you continue.” “It is absolutely essential that you continue.” “You have no other choice; you must go on.”
What Milgram reported
In the best-known version of the experiment, the results were striking: 65% of participants — 26 out of 40 —continued to the maximum 450-volt level. Many showed visible distress. Some protested, some laughed nervously, others questioned the procedure. A number asked whether they should stop. But under instruction, most continued. Milgram concluded that people are highly responsive to authority, even when obedience conflicts with their personal values. He argued that situational factors, not individual disposition alone, shaped behaviour. Several of those factors were consistent across variations. The physical presence of the authority figure increased compliance. The association with Yale lent credibility and trust. The gradual increase in voltage made each step feel incremental rather than extreme. Participants also appeared to shift responsibility onto the experimenter, seeing themselves as carrying out instructions rather than making independent decisions. When these conditions changed, obedience shifted. When the authority figure was absent or instructions were given remotely, compliance dropped. When other participants refused to continue, obedience fell sharply, in one condition, 36 out of 40 participants stopped early.
What the experiment suggested, and what later research found
Milgram’s work suggested that obedience is not simply a matter of personality but of context. Under certain conditions, individuals may comply with instructions they would otherwise reject. Later research complicated that picture. Studies and analyses have suggested that obedience depends not only on authority but on identification, how much participants agree with the goal of the authority figure and how strongly they identify with them. People are more likely to follow instructions when they see the authority as legitimate and aligned with their own values.
Stanley Milgram American social psychologist Stanley Milgram with the “shock generator” used in his famous experiment at Yale University in the 1960s/ Image: Britannica
Other analyses identified multiple variables affecting obedience, including proximity to the victim, the perceived legitimacy of the authority, and the presence of dissenting peers. These findings indicate that obedience is not automatic or uniform, but shaped by specific social conditions.
Ethical concerns and criticism
From the outset, the experiments raised serious ethical questions. Participants were deceived about the nature of the study and led to believe they were inflicting real harm. Many experienced significant psychological distress, including anxiety, tension and guilt. The experimenter’s insistence, particularly the instruction “You have no other choice; you must go on,” has been criticised as undermining the participant’s right to withdraw. Milgram stated that participants were debriefed afterwards, with the true nature of the experiment explained. However, later investigations have challenged how consistently and thoroughly this was done.Psychologist Gina Perry, an Australian researcher who examined archived recordings and documents, has written Behind the Shock Machine: The Untold Story of the Notorious Milgram Psychology Experiments after retracing Milgram’s steps and interviewing participants decades later. She argued that the reality of the experiment was more complex than the published account suggested, noting that what appeared as obedience could also resemble pressure: “The slavish obedience to authority we have come to associate with Milgram’s experiments comes to sound much more like bullying and coercion when you listen to these recordings,” Perry suggested in an article for Discover Magazine. Perry’s research also raised questions about debriefing, suggesting that many participants were not fully informed of the deception, sometimes for months or even years.
Questions about validity and replication
Further criticism has focused on how the results have been interpreted. The widely cited figure. 65% obedience, came from one specific variation. In other versions of the experiment, obedience rates were significantly lower, and in some cases no participants delivered the maximum shock. There is also evidence that some participants doubted the setup. Later analysis suggested that those who believed the shocks were real were less likely to continue, while those who suspected the learner was not actually being harmed were more willing to proceed. Replications of the study have produced mixed results. Ethical constraints have required modifications, for example, limiting maximum shock levels or screening participants more carefully. Some of these studies have found similar patterns of obedience, while others have argued that the differences in design make direct comparison difficult. The core issue remains unresolved: the original experiment cannot be fully replicated under modern ethical standards, which limits the ability to verify its findings in the same form.
Why the experiment still matters
Despite its problems, the Milgram experiment continues to hold a central place in psychology. It is frequently taught not only for what it claims to show about obedience, but also for what it reveals about the limits of experimental design.Its influence comes in part from how simple the setup was, a clear, controlled situation that produced results many people find both disturbing and familiar. It gives people a way to think about authority, responsibility and moral choices, while also prompting ongoing debate about how the experiment itself was conducted.As Gina Perry has argued, the study endures as a lasting narrative rather than a definitive answer. Reflecting on its legacy, she noted: “I think it leaves social psychology in a difficult situation. … it is such an iconic experiment. And I think it really leads to the question of why it is that we continue to refer to and believe in Milgram’s results. I think the reason that Milgram’s experiment is still so famous today is because in a way it’s like a powerful parable. It’s so widely known and so often quoted that it’s taken on a life of its own. … This experiment and this story about ourselves plays some role for us 50 years later.”
