The Stanford prison experiment

In 1971, a psychologist at Stanford turned a basement into a mock prison. He assigned students at random to be guards or prisoners and watched what happened. The story that became world-famous goes like this: within days, the guards spontaneously turned cruel, the prisoners broke down, and the experiment had to be halted early. For fifty years it was taught as proof that ordinary people become monsters when a situation hands them power, that circumstances, not character, drive terrible behaviour. It appeared in countless textbooks and shaped how we think about prisons, authority, and human nature. Then, in 2018, a researcher went into the archives and found the original recordings, which many had assumed were gone. On the tapes, you can hear the experimenter's staff coaching the guards, instructing them to be tough, telling them how to treat the prisoners. The cruelty was directed rather than spontaneous, and in places effectively scripted. One of the most famous studies in the history of psychology, and its headline result was not what it appeared to be.

Be most careful with the findings that feel the most obvious, because obvious is exactly what stops people from checking. The prison study survived for half a century not because its evidence was strong but because its story was satisfying and confirmed something people already suspected about human nature. When someone hands you a neat, powerful explanation of why people behave as they do, especially one repeated so often it feels like common sense, that is precisely the moment to ask where the original evidence actually is and how it was produced. Sometimes, as here, the answer is that the famous result was produced rather than observed, and almost nobody looked behind it for half a century.

Source: Zimbardo, 1971. The archival tapes and re-examination: Le Texier, 2019, American Psychologist.

Humankind

Rutger Bregman, 2020

Revisits the famous dark experiments about human nature and finds the evidence far weaker than the legend.