People Change in Situations: Authority, Social Proof, the Bystander Effect, Social Loafing, the Abilene Paradox and the Stanford Prison Experiment

Situations shape behaviour as much as character does

“I would never have done that.” Most of us think this when we read terrible news. The classic experiments of social psychology shook that belief: the power of the situation — an authority’s instructions, how others react, the mood of a group — turned out to be larger than we assume.

Because the field is famous, it has also attracted exaggeration. This article covers six phenomena with their original studies, and with what later research confirmed and where it drew limits.

Authority: when instructions beat conscience

In 1963 Stanley Milgram told participants to give a “learner” increasingly strong electric shocks for each wrong answer (there were no real shocks; the learner was an actor). Despite the screams, about 65% of participants went all the way to the maximum 450 volts — prompted only by an experimenter in a lab coat saying “please continue.”

In 2009 Burger repeated the study with an ethical stop at 150 volts and found obedience rates not very different from the 1960s. Yet in Milgram’s own variations, obedience fell sharply when the experimenter gave orders by phone or when participants saw another person refuse. Authority is strongest when it is close and no one is objecting.

Check question: “If I, not the person giving the order, were responsible for the outcome, would I still do it?”

Social proof: if everyone does it, it looks right

In the 1950s Solomon Asch had participants compare line lengths while confederates deliberately gave wrong answers. The correct answer was obvious, yet about three quarters of participants followed the wrong majority at least once; conformity occurred on about a third of trials.

Social proof is not only a force for bad. A hotel sign saying “most guests who stayed in this room reused their towels” produced more towel reuse than one appealing to the environment (Goldstein et al., 2008). Simply showing what is normal changes behaviour.

Check question: “Apart from ‘everyone does it,’ what is the evidence that this is right?”

The bystander effect: the more onlookers, the less help?

In 1968 Darley and Latané had participants hear, over an intercom, someone apparently having a seizure. About 85% of those who believed they were the only listener went to help, but only about 31% of those who believed four others were also listening did so. With more people, responsibility is diffused — “someone else will do it.”

The 1964 Kitty Genovese case, often cited as the inspiration, was later shown to have been badly exaggerated in the “38 witnesses did nothing” reporting (Manning et al., 2007). A meta-analysis spanning nearly fifty years of research (Fischer et al., 2011) found that the bystander effect weakens in clearly dangerous emergencies, and an analysis of real CCTV footage from several countries (Philpot et al., 2020) found that someone intervened in about nine out of ten public conflicts. More people can make any one person less likely to act while making it more likely that somebody does.

Check question: “What if ‘someone’ here is me?” When asking for help, point to one person: “You in the blue jacket, please call an ambulance.”

Social loafing: we try less in a group

In the 1910s Ringelmann observed that the more people pulled on a rope, the less force each one exerted. Later, Latané, Williams and Harkins (1979) showed with clapping and shouting tasks that individuals put in less effort in groups than alone — social loafing. A meta-analysis of 78 studies (Karau & Williams, 1993) found it grows when individual contributions are not visible and when the task feels unimportant.

Check question: “What is my share in this team, and can anyone see it?” If you lead a team, making roles and contributions visible is the surest remedy.

The Abilene paradox: everyone goes where no one wanted to go

Management scholar Jerry Harvey (1974) told of a family who, on a scorching afternoon, drove a long way to Abilene though none of them wanted to. Only afterwards did each admit, “I thought the others wanted to go.” Avoiding conflict, each swallowed their objection, and the group made a decision nobody wanted.

A related idea is Irving Janis’s (1972) groupthink: a cohesive group, eager to preserve unanimity, fails to weigh alternatives properly.

Check question: “If I had to name one reason against this decision, what would it be?” Assigning a devil’s advocate or collecting opinions anonymously first can help.

The Stanford Prison Experiment and the “Lucifer effect”

In 1971 Philip Zimbardo split students into guards and prisoners in a mock prison. Some guards became increasingly harsh, and the study was stopped after six days. Zimbardo later used it to argue for the “Lucifer effect”: bad situations can turn ordinary people cruel (Zimbardo, 2007).

Today the study should be cited with care. After reviewing archival material, Le Texier (2019) showed that the researchers conveyed instructions and expectations for the guards to be tough, that the sample was small and that there was no control condition. The broader point that situations influence behaviour is supported by other research, but this experiment alone cannot carry the claim that “anyone will become evil.”

Checklist at a glance

Phenomenon	Check question
Authority	If I were responsible for the outcome, would I still do it?
Social proof	Apart from “everyone does it,” what is the evidence?
Bystander effect	What if “someone” here is me?
Social loafing	What is my share, and is it visible?
Abilene paradox	What is one reason against this decision?
Power of the situation	How much is the mood of this room pushing my judgement?

Knowing the power of situations does not remove responsibility. If anything, knowing when you are likely to be swayed gives you room, in that moment, to step back and decide for yourself.

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References

• Milgram, S. (1963). Behavioral study of obedience. Journal of Abnormal and Social Psychology, 67(4), 371–378.
• Burger, J. M. (2009). Replicating Milgram: Would people still obey today? American Psychologist, 64(1), 1–11.
• Asch, S. E. (1956). Studies of independence and conformity: I. A minority of one against a unanimous majority. Psychological Monographs, 70(9), 1–70.
• Goldstein, N. J., Cialdini, R. B., & Griskevicius, V. (2008). A room with a viewpoint: Using social norms to motivate environmental conservation in hotels. Journal of Consumer Research, 35(3), 472–482.
• Darley, J. M., & Latané, B. (1968). Bystander intervention in emergencies: Diffusion of responsibility. Journal of Personality and Social Psychology, 8(4), 377–383.
• Manning, R., Levine, M., & Collins, A. (2007). The Kitty Genovese murder and the social psychology of helping: The parable of the 38 witnesses. American Psychologist, 62(6), 555–562.
• Fischer, P., et al. (2011). The bystander-effect: A meta-analytic review on bystander intervention in dangerous and non-dangerous emergencies. Psychological Bulletin, 137(4), 517–537.
• Philpot, R., Liebst, L. S., Levine, M., Bernasco, W., & Lindegaard, M. R. (2020). Would I be helped? Cross-national CCTV footage shows that intervention is the norm in public conflicts. American Psychologist, 75(1), 66–75.
• Latané, B., Williams, K., & Harkins, S. (1979). Many hands make light the work: The causes and consequences of social loafing. Journal of Personality and Social Psychology, 37(6), 822–832.
• Karau, S. J., & Williams, K. D. (1993). Social loafing: A meta-analytic review and theoretical integration. Journal of Personality and Social Psychology, 65(4), 681–706.
• Harvey, J. B. (1974). The Abilene paradox: The management of agreement. Organizational Dynamics, 3(1), 63–80.
• Janis, I. L. (1972). Victims of Groupthink. Houghton Mifflin.
• Zimbardo, P. (2007). The Lucifer Effect: Understanding How Good People Turn Evil. Random House.
• Le Texier, T. (2019). Debunking the Stanford Prison Experiment. American Psychologist, 74(7), 823–839.