Richard von Krafft-Ebing (1840-1902) was one of the most significant medical writers on sexology in the late 19th century (V. Bullough, 1994). His primary interest was what he considered “deviant” sexual behavior. Krafft-Ebing believed that deviant sexual behavior was the result of engaging in nonreproductive sexual practices, including masturbation. In 1886, he published an update of a book entitled Psychopathia Sexualis, which explored approximately 200 case histories of individuals who had experienced
sexual pathology, including people who had had sex with children (pedophiles) and homosexuals.
Although Krafft-Ebing supported sympathetic concern for those who expressed “deviations” and worked to help change existing laws that discriminated against them, he also increased suspicion about differences in sexuality by lumping all forms of sexual variations together as deviant.