2For Koehler's philosophical allegiances, see Mary Henle,ed.,The Selected Papers of Wolfgang Koehkr(New York:Liveright,1971).
3Perhaps the best and most accessible account of Gestalt psychology's empirical accomplishments (mostly before Hitler's rise to power)is Kurt Koffka, Principles of Gestalt Psychology(New York:Harcourt Brace,1935).
4The most detailed and authoritative volume on the classic learning theories is Ernest R.Hilgard,Theories of Learning,2d ed.(New York:Appleton-Century-Crofts, 1956).
