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The Milgram experiment

Twenty six of forty men pressed the last switch on a machine they believed was delivering 450 volts to a stranger. A man in a laboratory coat had told them to continue. The number is famous. The variations are the finding.

Published November 3, 2026. 5 sources at the foot of the page.

What it says

Milgram's setup is a study, not a theory. A volunteer was told he was the teacher in a memory experiment. The learner in the next room would get a shock for each wrong answer, rising 15 volts at a time. The learner was an actor. No shock was given.

When the volunteer hesitated, the experimenter used one of four set prods, ending in: you have no other choice, you must go on. In the baseline condition 26 of the 40 men, 65 percent, went to the top of the board.

Milgram then ran variations, and they move the number a great deal. Putting the learner in the same room lowers it. Moving the experimenter out of the room and onto a telephone lowers it further. Adding two other teachers who refuse lowers it most of all. Obedience was not a constant. It was a response to a situation that could be rearranged.

What changed the number

Each row is a variation Milgram ran against the same baseline.

  1. The learner in the same room

    Seeing and hearing the person made it harder to continue, and fewer did.

  2. The experimenter on the telephone

    Authority at a distance was easier to disobey, and some volunteers quietly gave lower shocks.

  3. Other teachers who refuse

    Two confederates walking out dropped obedience sharply. Company matters more than character.

  4. An ordinary man giving the orders

    Authority without the coat and the laboratory carried much less weight.

Where it came from

Milgram ran the studies at Yale in 1961 and 1962, in the years around the trial of Adolf Eichmann. The question behind them was explicitly about how ordinary people take part in atrocity. The first paper appeared in 1963 and the book, Obedience to Authority, in 1974.

The ethics are part of the record. Volunteers were deceived and many were visibly distressed. The study is now taught in every research ethics course as an example of what a review board exists to prevent.

What holds up, and what does not

The core result survives. Jerry Burger reproduced a version in 2009 that stopped at 150 volts. That is the point where most of Milgram's volunteers either continued or quit, and his rates were close to the originals.

The interpretation has moved. Alexander Haslam and Stephen Reicher argued in 2012 that the volunteers were not blindly obedient. They were engaged followers who identified with what they took to be a worthwhile scientific project. That reading fits which prods worked: the ones that mentioned science beat the one that simply ordered them on. Gina Perry's archival work, published in 2013, found the prods were often improvised, some volunteers doubted the shocks were real, and the reporting was tidier than the sessions.

What it does not mean

It does not show that anybody will do anything if told. The rates swing from very high to very low across the variations. A study of 40 men in one city in 1961 is not a measurement of human nature. What it shows is how much of a decision sits in the arrangement around it.

Check yourself

Three questions on what is above. Each answer says why.

  1. What was the baseline result of the 1963 study?

    1. 26 of 40 volunteers went to the highest switch
    2. All 40 volunteers refused at some point
    3. Half the volunteers walked out before the first shock
    Show the answer

    Answer: A. Milgram reported 26 of 40, or 65 percent, going to 450 volts in the baseline condition.

  2. Which variation reduced obedience the most?

    1. Moving the learner into the same room
    2. Adding two other teachers who refuse to continue
    3. Raising the voltage labels on the board
    Show the answer

    Answer: B. Seeing other people refuse was the strongest of the variations. The social situation, not the individual, carried the effect.

  3. Pick the statement that describes the Haslam and Reicher reading of the study.

    1. The volunteers obeyed blindly, without thinking
    2. The volunteers were engaged followers who identified with the project
    3. The results were fabricated
    Show the answer

    Answer: B. Their 2012 argument is about identification with a cause rather than blind obedience, and they point to which prods worked as evidence.

Sources

  1. Milgram, S. (1963). Behavioral study of obedience. Journal of Abnormal and Social Psychology, 67(4).
  2. Milgram, S. (1974). Obedience to Authority: An Experimental View. Harper and Row.
  3. Burger, J. M. (2009). Replicating Milgram: Would people still obey today? American Psychologist, 64(1).
  4. Haslam, S. A., and Reicher, S. D. (2012). Contesting the nature of conformity: What Milgram and Zimbardo's studies really show. PLOS Biology, 10(11).
  5. Perry, G. (2013). Behind the Shock Machine: The Untold Story of the Notorious Milgram Psychology Experiments. The New Press.

Practice it on Learn

Learn teaches this study in Studies that changed the field, the first unit of the Landmark studies track. The unit reads it beside the Bobo doll, Robbers Cave and Stanford prison experiments, each against its original paper.

Practice the Milgram experimentSee what Learn is

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