Gabriel Tarde (March 12, 1843 in Dordogne, France - May 13, 1904 in Paris) French sociologist and social psychologist who conceived sociology as based on small psychological interactions among individuals (much as if it were chemistry), the fundamental forces being imitation and innovation. Among the concepts that Tarde initiated were the "group mind" (taken up and developed by Gustave Le Bon, and sometimes advanced to explain so-called herd behaviour or crowd psychology), … Wikipedia
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