Charles-Marie Gustave Le Bon (1841 –1931) was a French polymath who wrote on anthropology, psychology, sociology, medicine and physics. He is best known for his 1895 work ‘The Crowd: A Study of the Popular Mind’, which is considered a seminal work of crowd psychology. In the book, Le Bon identifies the primary characteristics of crowd psychology as impulsiveness, irritability, incapacity to reason, the absence of critical judgement, and the exaggeration of feelings.

Le Bon claims that an individual immersed for some length of time in a crowd soon finds himself in a special psychological state, which resembles the state in which a hypnotized individual finds himself under the influence of the hypnotizer. One of Le Bon’s disturbing insights is that a man descends several rungs in the ladder of civilisation by the mere fact that he forms part of an organised crowd.