Die Homosexualität des Mannes und des Weibes is a classic 1914 book on homosexuality in men and women that was written by German sexologist Magnus Hirschfeld. A second edition was published in 1920. Hirschfeld was himself gay and an occasional crossdresser, known by other Berlin crossdressers as "Aunt Magnesia".Gherovici, P. (2011). Psychoanalysis Needs a Sex Change. Gay and Lesbian Issues and Psychology Review, 7(1), 3–18. https://criticaltheoryworkshop.com/wp-content/uploads/2016/03/gherovici_psychoanalysis_needs_a_sex_change-1.pdf "The term transvestite was coined by Magnus Hirschfeld in 1910 to describe those who occasionally wear clothes of the ‘other’ sex. Hirschfeld, a passionate sex reformer and an activist, struggled for the legalisation of homosexuality. He was also an occasional cross-dresser himself and a central political figure in Germany’s incipient field of sexology. Hirschfeld developed a theory of sexual intermediaries, contending that the existence of two opposite sexes was an oversimplification and that one could observe many varieties of intermediates. A pioneer advocate for transgender people, he argued that transgenderism could not be reduced either to homosexuality, fetishism, or to any form of pathology." The book was part of the series Handbuch der Gesamten Sexualwissenschaft in Einzeldarstellungen and was the third volume of this series. Die Homosexualität des Mannes und des Weibes was not translated until 2000, under the title The Homosexuality of Men and Women by Michael Lombardi-Nash. It has been said that the book was the most significant and authoritative text on homosexuality of its time. The book has often been overlooked in the English-speaking academia.

See also Die Transvestiten: Eine Untersuchung über den Erotischen Verkleidungstrieb (Hirschfeld, 1910)

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