Solomon Asch

Solomon Eliot Asch was born in Warsaw on 14 September 1907, then part of the Russian Empire, and moved with his family to the United States in 1920, settling on New York's Lower East Side. He took his bachelor's degree at the City College of New York in 1928 and his PhD at Columbia University in 1932.

His formative intellectual influence was Gestalt psychology, and above all Max Wertheimer, with whom he later worked closely. The Gestalt principle that a whole is organised differently from the sum of its parts runs through everything Asch did — including the conformity work, which he understood not as a study of weak-willed people but as a study of how a social context reorganises what a person perceives and reports.

At Swarthmore College in the early 1950s, Asch designed a deceptively simple task. A participant sat with a group of what they believed were fellow volunteers but who were in fact confederates. The group was shown a reference line and three comparison lines, and asked aloud which comparison line matched the reference. The correct answer was obvious.

On most trials the confederates answered correctly. On designated critical trials they all gave the same wrong answer, out loud, before the real participant's turn. The question was what the participant would then say.

About three quarters of participants went along with the obviously incorrect majority at least once, and roughly a third of all critical-trial responses conformed. In a control condition where participants wrote answers privately, the error rate was under one per cent. Follow-up variations showed that the decisive factor was unanimity: introducing a single confederate who broke ranks and gave the correct answer caused conformity to collapse, even when the rest of the majority remained.

The experiments are usually summarised as proof that people mindlessly follow the crowd. Asch's own reading was more interesting and more careful. He was struck that the majority of responses across all critical trials were still independent and correct, and that many participants who conformed did so while remaining privately certain the group was wrong.

In interviews afterwards, participants described very different internal experiences. Some genuinely doubted their own eyes. Some assumed they had misunderstood the task. Many knew the group was wrong and went along anyway to avoid standing out. Asch treated that variety as the real finding — that social pressure operates on perception, on judgement and on public behaviour by different routes.

Asch's other major contribution came earlier. His 1946 paper "Forming Impressions of Personality" showed that people do not build an impression of someone by adding up traits independently. Given the same list of adjectives with only "warm" swapped for "cold", participants produced substantially different overall impressions — evidence that some traits are central and reorganise the reading of everything around them. The same work demonstrated the primacy effect, where traits presented first weigh more heavily than those presented later.

He taught at Swarthmore for nearly twenty years, and also held posts at Rutgers, Harvard and the University of Pennsylvania. Stanley Milgram, who worked as his assistant, went on to design the obedience experiments — a direct descendant of Asch's question about how far social pressure can override individual judgement. Asch died in Haverford, Pennsylvania, on 20 February 1996.