In the eighteenth century, masturbation was extended from the moral to the medical sphere and conceptualized as being the cause of various deteriorative physical illnesses. In the nineteenth century, psychiatrists accepted that difficult to control masturbation was a feature of many mental disorders. They also believed that masturbation could play a casual role in a specific type of insanity with a distinctive natural history. In 1962, E.H. Hare published an article on the concept of masturbatory insanity that became an important explication of the masturbation and mental illness relationship in the history of psychiatry. Historical research published subsequent to Hare's article suggests several updates to his analysis. Hare did not note that the masturbation and mental illness relationship was promoted to the general public by quacks peddling quick cures. Hare emphasized psychiatrists’ condemnatory language only, neglecting the aspiration of psychiatrists to treat disorders caused by excessive masturbation, not punish the sin of masturbation. Hare recognized the importance of hebephrenia and neurasthenia to this history but attributed the decline of masturbation related mental illness in part to the rejection of an irrational, unscientific hypotheses about masturbation's causal role. As an alternative, we suggest that before the causal role of masturbation was widely abandoned, the concepts of hebephrenia and neurasthenia gained a competitive advantage and became primary diagnoses for cases that once would have been conceptualized as masturbatory insanity.