In the 1950s, a psychologist named Solomon Asch did a famous test. People looked at lines and chose the one with the same length. It was very easy.

But all the other people in the room were actors, and they gave the same wrong answer on purpose. About one-third of the answers followed the wrong group. But most answers were still correct. And with just one friend who gave the right answer, people followed the group much less.

In the 1950s, Solomon Asch asked people a simple question. Which of three lines was the same length as a target line? Everyone else in the group was secretly working with the researcher, and on certain trials they all gave the same wrong answer.

When people answered alone, they almost never made mistakes. In the group, however, about one-third of their answers followed the incorrect majority, and around three-quarters of the participants went along at least once. The experiment is often used to show how easily people give in to social pressure.

But look at the numbers again. About two-thirds of the answers stayed correct, and about a quarter of people never conformed at all. When just one other person gave the correct answer, conformity dropped sharply.

Solomon Asch's line-judgment studies are usually retold as proof that people cave in to a crowd. In the classic setup, one real participant sat among confederates who, on twelve of eighteen trials, all named an obviously wrong line. Alone, people erred less than one percent of the time. Facing a unanimous group, they went along with the majority on roughly a third of their answers, and about three-quarters conformed at least once.

Read the same numbers from the other side, though, and a different story appears. About two-thirds of responses stayed correct, roughly a quarter of participants never yielded, and Asch himself described the work as a study of independence as well as conformity. In later variations, a single ally who disagreed with the group cut conformity dramatically, while majorities larger than about three added little extra pressure.

A 1996 meta-analysis found that conformity in the United States fell after the 1950s and tended to be higher in more collectivist countries, but these were country-level correlations and do not prove that culture is the cause. A 2023 repeat with 210 participants found a conformity rate of about 33 percent, which dropped to about 25 percent when correct answers earned money.