In the 1950s, Asch performed what has since become one of the classic experiments in social psychology. He was interested in the effects of peer pressure, so designed an experiment to test our willingness to follow the herd.

In Asch’s study, groups of 5-8 people were assembled. Only one subject was an actual subject—the rest were Asch’s co-conspirators. Everyone was seated in pair of rows, with the subject seated towards the back of the second row. They were then told they were participating in a “vision test,” in which they would be shown a card with a line on it, followed by another card with three lines on it (labeled A, B, C). The “goal” of this test was to guess which line (A, B, C) matched (in length) the first line shown.

For the first two rounds of the test everything proceeds like normal. The experimenter held up a card with, say, a two inch line. Then everyone, including the study subject, guessed the matching line correctly. The same thing happened on the second round. But on the third round, something funny unfolds. The presenter showed a two inch line on the first card. On the second card, line B was obviously the two inch line and both A and C are shorter or longer respectively. But all of the conspirators gave the wrong answer—claiming the shorter line (say a one inch line) actually matched the two-inch line.

The question was what would the study subject do? Will they go along with the herd and give the wrong answer or will they be willing to stand out from the crowd and give the right one?