Psychopathia Sexualis

Psychopathia Sexualis: eine Klinisch-Forensische Studie (Sexual Psychopathy: A Clinical-Forensic Study, also known as Psychopathia Sexualis, with Especial Reference to the Antipathetic Sexual Instinct: A Medico-forensic Study) is an 1886 book by Richard Freiherr von Krafft-Ebing and one of the first texts about sexual pathology.

The book details a wide range of paraphilias and focuses on male homosexuality/bisexuality (the "antipathetic instinct" of the subtitle).

Masochism, which Freiherr von Krafft-Ebing focuses on at length, is, for example, defined as a particular erotic sensibility, in which the individual is, "in his sexual feelings and thoughts, dominated by the idea of being absolutely and unconditionally subjected to a person of the other sex".

[1] The Psychopathia Sexualis is notable for being one of the earliest works on homosexuality.

The book had a considerable influence on continental European forensic psychiatry in the first part of the 20th century.