Stanley Milgram

Stanley Milgram (August 15, 1933 – December 20, 1984) was an American social psychologist. He served on the faculty at Yale University, Harvard University, and the City University of New York. While at Yale, he conducted a seminal series of experiments on obedience to authority, which have come to be known simply as the infamous "Milgram experiment." Milgram conducted a number of other studies, including the small-world experiment (the source of the six degrees of separation concept), and also introduced the concept of familiar strangers.

Did you know?
Stanley Milgram's experiments showed that people may act in inhumane ways when ordered to do so by an authority figure and when their peers also act in the same way

Milgram's experiments shocked people with their implications about the dark aspects of human nature, especially since they showed that apparently normal people would behave in inhumane ways. For Milgram, however, they were more about the influence of the group on the individual than individual nature itself. He had begun his research asking whether it could be that those on trial as war criminals were just following orders, and would others have done the same. When the My Lai Massacre occurred in Vietnam in 1968, his work was used to explain the behavior of those involved.


Milgram showed that human beings, people who one would not expect to behave inhumanely, are nonetheless capable of acting in inhumane ways when ordered to do so by an authority figure and when their peers also acted in the same way. Such obedience and conformity, Milgram noted, are essential aspects of social behavior, allowing society to function in an organized fashion. The problem, obviously, comes when authority is wrong. Milgram's solution, based on his research, was that people of conscience would find strength in numbers to resist misguided authority. Thus, although shocking, Milgram's contribution to our understanding of human nature gives much hope for a better world.


Stanley Milgram was born in New York City on August 15, 1933, the second of three children. His parents were immigrants from Europe and ran a bakery in New York. Stanley spent his early years in the city, graduating from James Monroe High School in 1950. One of his classmates was Philip Zimbardo, who also became an influential social psychologist, famous for the Stanford prison experiment.

Although considered one of the most important psychologists of the twentieth century, Stanley Milgram took no psychology courses as an undergraduate at Queens College, New York, where he earned his Bachelor's degree in political science in 1954. He applied to a Ph.D. program in social psychology at Harvard University and was initially rejected due to lack of psychology background. He was accepted in 1954 after taking six courses in psychology, and graduated with his Ph.D. in 1960.

Milgram's dissertation, under the mentorship of Gordon Allport, was a cross-cultural study of conformity carried out in Norway and France. In 1955 Solomon Asch had been a visiting lecturer at Harvard, and Milgram was his teaching assistant. He became very familiar with Asch's conformity experiments, and modified Asch's procedure to use sound (tones) instead of visual stimuli (lines) in his research. Milgram also used tape-recorded answers from other subjects to create the peer group, noting that this method had the advantages that "tapes do not have to be paid by the hour and they are always available."[1]

In 1959 and 1960, Milgram worked for Asch at the Institute for Advanced Study in Princeton, helping him edit his book on conformity. He regarded Asch as the most important scientific influence on his research.[2] After receiving his Ph.D., in September of 1960 Milgram was appointed assistant professor of psychology at Yale University. He immediately began pilot studies on obedience and began the formal experiments in the summer of 1961. Going beyond Asch's conformity work, Milgram was curious as to whether social influence would have such power in situations of greater consequence than judgments of lines or tones. His research into obedience to authority shocked the world.

During his three years at Yale, Milgram met and married Alexandra "Sasha" Menkin. They had two children.

In 1963, Milgram submitted the results of his research in the article "Behavioral study of Obedience." Most likely because of this controversial "Milgram Experiment," Milgram was denied tenure at Harvard after becoming an assistant professor there. He subsequently accepted an offer to become a tenured full professor at the Graduate Center of the City University of New York (CUNY).

In the ensuing controversy that erupted, the APA held up his application for membership for a year because of questions about the ethics of his work, but finally granted him full membership. Ten years later, in 1974, Milgram published Obedience to Authority and was awarded the annual social psychology award by the AAAS (mostly for his work over the social aspects of obedience).

Inspired in part by the 1961 trial of Adolf Eichmann, his work was later used to explain the 1968 My Lai massacre (including authority training in the military and on depersonalizing the "enemy" through racial and cultural differences).

Stanley Milgram died of a heart attack on December 20, 1984 at the age of 51 in the city of his birth, New York.


Milgram is most famous for his work on obedience, with a particularly shocking study becoming known simply as the "Milgram experiment." In addition to his studies of obedience and conformity, Milgram investigated a number of other issues in social psychology. Of particular note are his work on the "small world phenomenon" and the "familiar stranger."

Milgram also conducted a study of the effects of television on social behavior. He published an article on urban life in Science in 1970. This reflected his love of city life and helped initiate the psychological study of urban life.

Obedience to authority

While at Yale University, Milgram conducted what is known today as the infamous Milgram experiment, a seminal series of social psychology experiments, which measured the willingness of study participants to obey an authority figure who instructed them to perform acts that conflicted with their personal conscience. Milgram first described his research in 1963 in an article published in the Journal of Abnormal and Social Psychology,[3] and later discussed his findings in greater depth in his 1974 book, Obedience to Authority: An Experimental View.[4]

Advertisement for the recruiting of the Milgram experiment subjects

The experiments began in July 1961, three months after the start of the trial of Nazi war criminal Adolf Eichmann in Jerusalem. Milgram devised the experiments to answer this question: "Could it be that Eichmann and his million accomplices in the Holocaust were just following orders? Could we call them all accomplices?"[4]

After the pilot study with Yale students, Milgram advertised for members of the public to participate in an experiment that was described as a study of learning and memory. As a result, "ordinary" people were tested, people drawn from every stratum of New Haven life including professionals, white collar workers, unemployed persons, and industrial workers.[5] The role of the experimenter was played by a stern, impassive biology teacher dressed in a white technician's coat, and the learner (supposedly another volunteer, but in reality a confederate of the experimenter) was played by a 47 year old Irish-American accountant trained to act for the role. When they arrived, the participant and the confederate were told by the experimenter that they would be participating in an experiment helping his study of memory and learning in different situations.[3]

Two slips of paper were then presented to the participant and to the confederate. The participant was led to believe that one of the slips said "learner" and the other said "teacher," and that he and the confederate had been given the slips randomly. In fact, both slips said "teacher," but the confederate claimed to have the slip that read "learner," thus guaranteeing that the participant would always be the "teacher." At this point, the "teacher" and "learner" were separated into different rooms where they could communicate but not see each other. In one version of the experiment, the confederate was sure to mention to the participant that he had a heart condition.[3]

The experimenter (E) orders the teacher (T), the subject of the experiment, to give what the subject believes are painful electric shocks to a learner (L), who is actually an actor and confederate. The subjects believed that for each wrong answer, the learner was receiving actual shocks, but in reality there were no shocks. Being separated from the subject, the confederate set up a tape recorder integrated with the electro-shock generator, which played pre-recorded sounds for each shock level.

The "teacher" was given a 45-volt electric shock from the electro-shock generator as a sample of the shock that the "learner" would supposedly receive during the experiment. The "teacher" was then given a list of word pairs which he was to teach the learner. For every incorrect response the teacher was to administer a shock to the learner, with the voltage increasing for each wrong answer.[3]

The subjects believed that for each wrong answer, the learner was receiving actual shocks. In reality, there were no shocks. After the confederate was separated from the subject, the confederate set up a tape recorder integrated with the electro-shock generator, which played pre-recorded sounds for each shock level. After a number of voltage level increases, the actor started to bang on the wall that separated him from the subject. After several times banging on the wall and complaining about his heart condition, all responses by the learner would cease.[3]

At this point, many people indicated their desire to stop the experiment and check on the learner. Some test subjects paused at 135 volts and began to question the purpose of the experiment. Most continued after being assured that they would not be held responsible. A few subjects began to laugh nervously or exhibit other signs of extreme stress once they heard the screams of pain coming from the learner.[3]

If at any time the subject indicated his desire to halt the experiment, he was given a succession of verbal prods by the experimenter,[3] in this order:

  1. Please continue.
  2. The experiment requires that you continue.
  3. It is absolutely essential that you continue.
  4. You have no other choice, you must go on.

If the subject still wished to stop after all four successive verbal prods, the experiment was halted. Otherwise, it was halted after the subject had given the maximum 450-volt shock three times in succession.

Before conducting the experiment, Milgram polled 14 Yale University senior-year psychology majors as to what they thought would be the results. All of the poll respondents believed that only a few (average 1.2 percent) would be prepared to inflict the maximum voltage. Milgram also informally polled his colleagues and found that they, too, believed very few subjects would progress beyond a very strong shock.[3]

In Milgram's first set of experiments, 65 percent (26 of 40)[3] of experiment participants administered the experiment's final 450-volt shock, though many were very uncomfortable doing so; at some point, every participant paused and questioned the experiment, some said they would refund the money they were paid for participating in the experiment. No participant steadfastly refused to administer shocks before the 300-volt level.[3] Later, Milgram and other psychologists performed variations of the experiment throughout the world, with similar results.[5]

In Obedience to Authority: An Experimental View published in 1974, Milgram described nineteen variations of his experiment, testing variables that might be expected to influence the subjects' behavior. For example, if participants received telephonic instructions from the experimenter, compliance decreased to 21 percent; interestingly, some participants deceived the experimenter by pretending to continue the experiment. In the variation where the "learner's" physical immediacy was closest, wherein participants had to physically hold the "learner's" arm onto a shock plate, compliance decreased. Under that condition, 30 percent of participants completed the experiment.

Milgram also combined the power of authority with that of conformity. In those experiments, the participant was joined by one or two additional "teachers" (also actors, like the "learner"). The behavior of the participants' peers strongly affected the results. In one variation, the actual subject did not pull the shock lever; instead he only conveyed information to the peer (a confederate) who pulled the lever. Thus, according to Milgram, the subject shifts responsibility to another person and does not blame himself for what happens.

Milgram summarized the experiments in his 1974 article, "The Perils of Obedience," writing:

The legal and philosophic aspects of obedience are of enormous importance, but they say very little about how most 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' [participants'] strongest moral imperatives against hurting others, and, with the subjects' [participants'] 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.

Ordinary people, simply doing their jobs, and without any particular hostility on their part, can become agents in a terrible destructive process. Moreover, even when the destructive effects of their work become patently clear, and they are asked to carry out actions incompatible with fundamental standards of morality, relatively few people have the resources needed to resist authority.[5]

Milgram elaborated two theories explaining his results:

  • The first is the theory of conformism, based on Solomon Asch's work, describing the fundamental relationship between the group of reference and the individual person. A subject who has neither ability nor expertise to make decisions, especially in a crisis, will leave decision making to the group and its hierarchy. The group is the person's behavioral model.
  • The second is the agentic state theory, wherein the essence of obedience consists in the fact that a person comes to view himself as the instrument for carrying out another person's wishes, and he therefore no longer sees himself as responsible for his actions. Once this critical shift of viewpoint has occurred in the person, all of the essential features of obedience follow.

Thomas Blass of the University of Maryland Baltimore County performed a meta-analysis on the results of repeated performances of the experiment. He found that the percentage of participants who are prepared to inflict fatal voltages remains remarkably constant, 61–66 percent, regardless of time or place.[6][2]

Milgram created a documentary film titled Obedience showing the experiment and its results. He also produced a series of five social psychology films, some of which dealt with his experiments.[7]

Small world phenomenon

Beginning in 1967, Milgram carried out a series of experiments, known as the "small world experiment," examining the average path length for social networks of people in the United States. The research was groundbreaking in that it suggested that human society is a small world type network characterized by short path lengths. The experiments are often associated with the phrase "six degrees of separation," although Milgram did not use this term himself.

His experiment was conceived in an era when a number of independent threads were converging on the idea that the world is becoming increasingly interconnected. Mathematician Manfred Kochen and political scientist Ithiel de Sola Pool had written a mathematical manuscript, "Contacts and Influences," while working at the University of Paris in the early 1950s, during a time when Milgram visited and collaborated in their research. Their unpublished manuscript circulated among academics for over twenty years before publication in 1978. It formally articulated the mechanics of social networks, and explored the mathematical consequences of these (including the degree of connectedness). The manuscript left many significant questions about networks unresolved, and one of these was the number of degrees of separation in actual social networks.

Milgram's work developed out of a desire to learn more about the probability that two randomly selected people would know each other.[8] This is one way of looking at the small world problem. An alternative view of the problem is to imagine the population as a social network and attempt to find the average path length between any two nodes. Milgram's experiment was designed to measure these path lengths by developing a procedure to count the number of ties between any two people.

Though the experiment went through several variations, Milgram typically chose individuals in the U.S. cities of Omaha, Nebraska and Wichita, Kansas to be the starting points and Boston, Massachusetts to be the end point of a chain of correspondence. These cities were selected because they represented a great distance in the United States, both socially and geographically.[9]

Information packets were initially sent to randomly selected individuals in Omaha or Wichita. They included letters, which detailed the study's purpose, and basic information about a target contact person in Boston. It additionally contained a roster on which they could write their own name, as well as business reply cards that were pre-addressed to Harvard University.

Upon receiving the invitation to participate, the recipient was asked whether he or she personally knew the contact person described in the letter. If so, the person was to forward the letter directly to that person. For the purposes of this study, knowing someone "personally" is defined as knowing them on a first-name basis.

In the more likely case that the person did not personally know the target, then the person was to think of a friend or relative they know personally that is more likely to know the target. They were then directed to sign their name on the roster and forward the packet to that person. A postcard was also mailed to the researchers at Harvard so that they could track the chain's progression toward the target.

When and if the package eventually reached the contact person in Boston, the researchers could examine the roster to count the number of times it had been forwarded from person to person. Additionally, for packages that never reached the destination, the incoming postcards helped identify the break point in the chain.

Shortly after the experiments began, letters would begin arriving to the targets and the researchers would receive postcards from the respondents. Sometimes the packet would arrive to the target in as few as one or two hops, while some chains were composed of as many as nine or ten links. However, a significant problem was that often people refused to pass the letter forward, and thus the chain never reached its destination. In one case, 232 of the 296 letters never reached the destination.[8]

However, 64 of the letters eventually did reach the target contact. Among these chains, the average path length fell around 5.5 or six. Hence, the researchers concluded that people in the United States are separated by about six people on average. And, although Milgram himself never used the phrase "Six Degrees of Separation," these findings likely contributed to its widespread acceptance.[9]

Familiar stranger

Milgram continued to conduct creative research projects. In 1971 he carried out two independent research projects, one at CUNY and the other at a train station, on urban life. His findings became known as the "familiar stranger," from his article "The Familiar Stranger: An Aspect of Urban Anonymity" published in Milgram (1977)[10].

A "familiar stranger" is an individual who is recognized from regular activities, but with whom one does not interact. Somebody who is seen daily on the train or at the gym, but with whom one does not otherwise communicate, is an example of a familiar stranger. If such individuals meet in an unfamiliar setting, for example while traveling, they are more likely to introduce themselves than would perfect strangers, since they have a background of shared experiences.

Milgram published a second paper on the subject, "Frozen World of the Familiar Stranger," in 1974. It appeared in the magazine Psychology Today. The familiar stranger has since become a popular concept in research about social networks.


The Milgram Experiment raised questions about the ethics of scientific experimentation because of the extreme emotional stress suffered by the participants. In Milgram's defense, 84 percent of former participants surveyed later said they were "glad" or "very glad" to have participated, 15 percent chose neutral responses (92 percent of all former participants responding).[4] Many later wrote expressing thanks. Milgram repeatedly received offers of assistance and requests to join his staff from former participants. Six years later (at the height of the Vietnam War), one of the participants in the experiment sent correspondence to Milgram, explaining why he was glad to have participated despite the stress:

While I was a subject in 1964, though I believed that I was hurting someone, I was totally unaware of why I was doing so. Few people ever realize when they are acting according to their own beliefs and when they are meekly submitting to authority. … To permit myself to be drafted with the understanding that I am submitting to authority's demand to do something very wrong would make me frightened of myself. … I am fully prepared to go to jail if I am not granted Conscientious objector status. Indeed, it is the only course I could take to be faithful to what I believe. My only hope is that members of my board act equally according to their conscience.

The experiments provoked emotional criticism more about the experiment's implications than with experimental ethics. In the journal Jewish Currents, Joseph Dimow, a participant in the 1961 experiment at Yale University, wrote about his early withdrawal as a "teacher," suspicious "that the whole experiment was designed to see if ordinary Americans would obey immoral orders, as many Germans had done during the Nazi period".[11] Indeed, that was one of the explicitly-stated goals of the experiments. Quoting from the preface of Milgram's book, Obedience to Authority: "The question arises as to whether there is any connection between what we have studied in the laboratory and the forms of obedience we so deplored in the Nazi epoch."

The Milgram Experiment and the later Stanford prison experiment led by Philip Zimbardo at Stanford University were frightening in their implications about the danger lurking in human nature's dark side.[2] For Milgram, however, they were more about the influence of the group on the individual than individual behavior itself:

The social psychology of this century reveals a major lesson: often it is not so much the kind of person a man is as the kind of situation in which he finds himself that determines how he will act.[4]

He saw his experiments as revealing the power of authority to triumph over conscience:

Each individual possesses a conscience which to a greater or lesser degree serves to restrain the unimpeded flow of impulses destructive to others. But when he merges his person into an organizational structure, a new creature replaces autonomous man, unhindered by the limitations of individual morality, freed of humane inhibition, mindful only of the sanctions of authority.[4]

Milgram's obedience studies revealed that people from all walks of life have a strong predisposition to obey authority. His work, repeated under many different conditions, revealed that human beings naturally tend to conformity:

We do not observe compliance to authority merely because it is a transient cultural or historical phenomenon, but because it flows from the logical necessities of social organization. If we are to have social life in any organized form—that is to say, if we are to have society—then we must have members of society amenable to organizational imperatives.[2]

Equally, Milgram suggested that when men of conscience wish to stand up to authority, they will find strength in numbers. For conformity can be used to bring together a group that balances the power of authority:

When an individual wishes to stand in opposition to authority, he does best to find support for his position from others in his group. The mutual support provided by men for each other is the strongest bulwark we have against the excesses of authority.[4]

Major publications

  • Milgram, Stanley. "Nationality and Conformity." Scientific American 205(34) (1961): 45-51.
  • Milgram Stanley. "Behavioral study of obedience." Journal of Abnormal and Social Psychology 67 (1963): 371-378.
  • Milgram, Stanley. "The Small World Problem." Psychology Today 6 (1967): 60-67
  • Milgram, Stanley. "The Experience of Living in Cities." Science 167(13) (1970): 1461-1468.
  • Milgram, Stanley. Obedience to Authority: An Experimental View. Harper Perennial, 1983 (original 1974). ISBN 006131983X
  • Milgram, Stanley. "The Perils of Obedience." Harper's Magazine (1974). Retrieved June 25, 2008.
  • Milgram, Stanley. "Frozen world of the familiar stranger." Psychology Today 8 (1974): 70-74.
  • Milgram, Stanley. Psychology in Today's World. Educational Associates/ Little Brown and Company, 1975.
  • Milgram, Stanley. The Individual in a Social World: Essays and Experiments. Longman Higher Education, 1977. ISBN 0201043823
  • Milgram, Stanley. "The Familiar Stranger: An Aspect of Urban Anonymity." In The Individual in a Social World: Essays and Experiments, Stanley Milgram and Thomas Blass. Pinter & Martin Ltd, 2010 (original 1977). ISBN 978-1905177127
  • Milgram, Stanley and R. Lance Shotland. Television and Anti-social Behaviour. Academic Press, 1974. ISBN 978-0124963504

Media depictions

  • The Human Behavior Experiments (2006) is a documentary by Alex Gibney about major experiments in social psychology, shown along with modern incidents highlighting the principles discussed. Along with Milgram's study in obedience, the documentary shows the "diffusion of responsibility" study of John Darley and Bibb Latané and the Stanford Prison Experiment of Phillip Zimbardo.[12]
  • Obedience is a black-and-white film of the experiment, shot by Milgram himself.[13]
  • Atrocity (2005) is a film re-enactment of the Milgram Experiment.[14]
  • UK conceptual artist Rod Dickinson recreated one condition of the Milgram obedience experiment as a performance art installation, The Milgram Re-enactment (2002)[15]
  • The Tenth Level (1975) was a CBS television film about the experiment, featuring William Shatner, Ossie Davis, and John Travolta.[16]


  1. Stanley Milgram, "Nationality and Conformity," Scientific American 205(34) (1961): 45-51.
  2. 2.0 2.1 2.2 2.3 Thomas Blass, The Man Who Shocked the World Psychology Today (Mar/Apr 2002). Retrieved June 12, 2008.
  3. 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 Stanley Milgram, "Behavioral Study of Obedience" Journal of Abnormal and Social Psychology 67(4) (1963): 371-378.
  4. 4.0 4.1 4.2 4.3 4.4 4.5 Stanley Milgram, Obedience to Authority; An Experimental View (Harpercollins, 1974, ISBN 006131983X).
  5. 5.0 5.1 5.2 Stanley Milgram, "The Perils of Obedience" as it appeared in Harper's Magazine. Abridged and adapted from Stanley Milgram Obedience to Authority. (1974). Retrieved June 12, 2008.
  6. Thomas Blass, "The Milgram paradigm after 35 years: Some things we now know about obedience to authority," Journal of Applied Social Psychology 25 (1999): 955-978.
  7. Milgram's films. Retrieved January 21, 2011.
  8. 8.0 8.1 Jeffrey Travers and Stanley Milgram, "An Experimental Study of the Small World Problem." Sociometry 32(4) (1969): 425-443.
  9. 9.0 9.1 Albert-Laszlo Barabasi, Linked: How Everything Is Connected to Everything Else and What It Means (New York, NY: Plume, 2003, ISBN 978-0452284395).
  10. Stanley Milgram, "The Familiar Stranger: An Aspect of Urban Anonymity" in The Individual in a Social World: Essays and Experiments, Stanley Milgram and Thomas Blass, (1977, Pinter & Martin Ltd, 2010, ISBN 978-1905177127).
  11. Joseph Dimow, "Resisting Authority: A Personal Account of the Milgram Obedience Experiments" Jewish Currents (2004). Retrieved June 12, 2008.
  12. The Human Behavior Experiments at Retrieved January 21, 2011.
  13. Milgram Media Offered by Penn State Media Sales Retrieved June 12, 2008.
  14. Atrocity Museum of the Moving Image. Retrieved June 12, 2008.
  15. Milgram Re-enactment (2002). Retrieved January 21, 2011.
  16. The Tenth Level Internet Movie Database. Retrieved January 21, 2011.


  • Barabasi, Albert-Laszlo. Linked: How Everything Is Connected to Everything Else and What It Means. New York, NY: Plume, 2003 ISBN 978-0452284395
  • Blass, Thomas. The Man Who Shocked the World: The Life and Legacy of Stanley Milgram. New York, NY: Basic Books, 2004. ISBN 0738203998
  • Blass, Thomas. "The Milgram paradigm after 35 years: Some things we now know about obedience to authority." Journal of Applied Social Psychology 25 (1999): 955-978.
  • Dimow, Joseph. "Resisting Authority: A Personal Account of the Milgram Obedience Experiments." Jewish Currents (2004).
  • Milgram, Stanley. "Behavioral Study of Obedience." Journal of Abnormal and Social Psychology 67(4) (1963): 371-378
  • Milgram, Stanley, and Thomas Blass. The Individual in a Social World: Essays and Experiments. Stanley Milgram Pinter & Martin Ltd, 2010 (original 1977). ISBN 978-1905177127
  • Miller, Arthur G. The Obedience Experiments: A Case Study of Controversy in Social Science. New York, NY: Praeger, 1986. ISBN 978-0275920128
  • Parker, Ian. "Obedience." Granta 71 (2000). Retrieved June 25, 2008.
  • Tarnow, Eugen. "Towards the Zero Accident Goal: Assisting the First Officer Monitor and Challenge Captain Errors". Journal of Aviation/Aerospace Education and Research 10(1) (2000). Retrieved June 25, 2008.
  • Travers, Jeffrey, and Stanley Milgram. "An Experimental Study of the Small World Problem." Sociometry 32(4) (1969): 425-443.
  • Wu, William. "Practical Psychology: Compliance: The Milgram Experiment." Retrieved June 25, 2008.

External links

All Links retrieved October 27, 2014.


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