Founded by Max Wertheimer ,Gestalt psychology surfaced as a theoretical school in Germany early in the 20th century. Gestalt psychology was based on the belief that the whole is greater than the sum of its parts. Gestalt is German for "form" or "shape". An example of this fundamental principle is provided by the phi phenomenon, first described by Wertheimer. The phi phenomenon is the illusion of movement created by presenting visual stimuli in rapid succession. For example, movies and TV consist of separate still pictures projected rapidly one after the other. Although we see smooth motion, in reality the moving objects merely take a slightly different position in successive frames. The same principle is illustrated by electric signs, such as those on movie marquees or at road construction sites. The bulbs going on and off in turn, with the appropriate timing, give the impression of motion. Of course, nothing in the sign really moves. The elements are stationary. Working as a whole, however, they have a property that isn't evident in any of the parts. Gestalt psychology's emergence in 1912 was in part a reaction against structuralism, an influential school of thought in Germany at the time. Obviously, the structuralists' interest in breaking conscious experience into its component parts seemed ill advised in light of the Gestalt theorists' demonstration that the whole can be much greater than the sum of its parts. Nazi persecutions in Germany eventually forced the leading Gestalt theorists; Wertheimer, Kurt Koffka, and Wolfgang Kohler; to move to the United States, where they attacked the theoretical edifice of behaviorism. They took issue with the behaviorists on two counts. First, they saw the behaviorists' attempt to analyze behavior into stimulus-response bonds as another ill-fated effort to carve the whole into its parts. Second, they felt that psychology should continue to study conscious experience rather than shift its focus to observable behavior.
