In the book The Crowd, Le Bon argues that there are several characteristics ofcrowd psychology: "impulsiveness, irritability, incapacity to reason, the absence of judgement of the critical spirit, the exaggeration of sentiments, and others...".

Gustave Le Bon (1841-1931) was a prominent French polymath born in Nogent-le-Rotrou, France. His areas of interest included topics such as sociology, psychology, anthropology and others. He is best known for his work The Crowd: A Study of the Popular Mind.