Gustave Le Bon was born on May 7, 1841, in Nogent-le-Retrou, France. After finishing his medical studies in 1866, Le Bon practiced medicine in Paris. He also traveled extensively throughout the countries of Europe, Asia, and North Africa and composed a series of travelogues and works on archeology and anthropology, including "La Civilisation des Arabes" and "Les Civilisations de l'Inde" (both 1884). Le Bon came to international renown primarily because of his book "Psychologie des foules" (1895), with which he became the founder of mass psychology. He proposed that, even in a highly developed culture, the individual in a crowd loses his capacity for critical thinking and behaves in a affective, primitive, barbaric way. According to Le Bon, the individual as part of a crowd is much more easily convinced and is subject to the psychological contagion which allows leaders to easily steer crowds where they please. In addition to publishing numerous works on other subjects, such as hygiene, psysiology, politics, and sociology, Le Bon took an active part in the intellectual life of his time and maintained contact to personages such as the philosophers Paul Valéry and Henri Bergson. Gustave Le Bon died on December 15, 1931, in Paris.