Peller traces the influence of Darwinian psychology which has had a particular influence on general and child psychology. It emphasizes the fight for survival as the chief influence shaping behavior and upon localization of conflict between the organism and its environment. On the other hand psychoanalytic theory and observation sees pleasure and pain as determinants of behavior and the locus of significant conflict as internal. Peller argues that psychoanalytic psychology refutes or limits the validity of most of Darwin's views of psychology. Freud's early work was close to many Darwinian views. Later changes in psychoanalytic theory share in the movement away from Darwinism.