Iwan Bloch

Together with Magnus Hirschfeld and Albert Eulenburg, Bloch is known for having proposed the new concept of a science of sexuality (Sexualwissenschaft) or sexology.

In 1906 he wrote in German the book Das Sexualleben unserer Zeit in seinen Beziehungen zur modernen Kultur which was translated as The Sexual Life of our Time in its Relations to Modern Civilization, a complete encyclopedia of the sexual sciences in their relation to modern civilization.

[1][2] He is also known for having discovered the Marquis de Sade's manuscript of The 120 Days of Sodom, which had been believed to be lost, and published it under the pseudonym Eugen Dühren in 1904.

His father Louis Bloch (1846–1892) was a cattle dealer from Bassum who had a total of five children with his wife Rosa Lisette Rosette, née Meyer (1845–1921).

[4] Iwan Bloch began the publication of his Handbuch der gesamten Sexualwissenschaft in Einzeldarstellungen (Handbook of Sexology in its Entirety Presented in Separate Studies) in 1912.