Psychosis theory held that sex offenders must be "crazy" or "sick in the head" to commit rape and sexual assault on children. In the vast majority of cases, however, there is little basis for a diagnosis of mental illness as a causal explanation in the sense that other personality disorders are defined. Under physiological theory, neurological and hormonal factors are the most promising areas for physiological research, since either would involve measurable and potential alterable conditions. Related to, but not synonymous with, the theory of psychosis are the early theories of sexual offending as a symptom of intrapsychic conflict. Learning theory notes that although the capacity for sexuality is inborn, and many biological factors create the preconditions necessary for sexual functions, the ways in which people manifest their sexuality are learned. The concepts of normal and deviant sexuality are based in societal norms and values; thus, the evaluation of sexual behavior is based on learning what is acceptable within a given culture. Many theories of child development (developmental theories) have been advanced in this century and provide a basis for exploration of both normal and deviant development. Other theories of the etiology of sexual offending include attachment theories, cognitive theory, addictive theory, family systems theories, and integrative theories. 1 table and 51 references