Instincts of the Herd in Peace and War

Trotter (1872-1939) was an English surgeon and pioneer in neurosurgery who was also known for his studies in social psychology, most notably for his concept of herd instinct. He first outlined his theory on the subject in two papers published in 1908 and '09, before this popular work appeared in 1916 which was highly influential in the development of group dynamics and crowd psychology.