Georges Sorel's (1847–1922) Réflexions sur la violence supplied a theoretical background for the syndicalist movement, an outgrowth of anarchism that aimed at destruction of the state through a general strike engineered by trade unions.
Gestalt psychology was expounded by Max Wertheimer (1880–1943) and developed further by Kurt Koffka (1886–1941) and Wolfgang Köhler (1887–1967). (See Intellectual and Religious Trends)
