Asch conformity experiments

In psychology, the Asch conformity experiments were a series of studies testing the Asch paradigm, directed by Solomon Asch, studying if and how individuals yielded to or defied a majority group and the effect of such influences on beliefs and opinions. Developed in the 1950s, the methodology remains in use by many researchers.

Source: Wikipedia — Asch conformity experiments (CC BY-SA 4.0)