This chapter deals with an evaluation of the continuing relevance of Gestalt theory for contemporary psychology. It reviews the school's leaders before examining historical antecedents and major themes in the Gestalt system. In 1924, Kurt Koffka published Growth of the Mind, a creative and influential book that demonstrated the relevance of Gestalt principles to developmental psychology. Holistic philosophies from Spinoza and others further shaped the intellectual foundations of Gestalt psychology, and Wade includes art as a precursor to Gestalt. Gestalt psychology is also often regarded as a system that is more akin to rationalism than empiricism. The work of physicist Ernst Mach also influenced Gestalt psychologists. The formal founding of Gestalt psychology is generally dated to 1910, when Max Wertheimer was inspired by apparent movement he observed during a train ride to a vacation in the Rhineland. The best-known work on learning in the Gestalt literature is Kohler's classic book The Mentality of Apes.