Otto Weininger (1880–1903) is a notorious figure in European history.1 A Jewish intellectual of Vienna, Weininger committed suicide at the age of 23 after publishing a single book based on his doctoral dissertation, Geschlecht und Charakter (Sex and Character, 1903). The work was admired by some of the greatest intellects of our century—Franz Kafka, Ludwig Wittgenstein, James Joyce, Karl Kraus, August Strindberg. More recently, it has attained virtually legendary status among scholars as an exemplary text of European misogyny and antisemitism. While Geschlecht und Charakter is certainly unrivaled as a compendium of turn-of-the-century prejudices, stereotypes, and anxieties, it is not simply a deranged thinker's chronicle of personal nightmares. This fact has been obscured due to the failure of recent scholars to situate Weininger and his work in the intellectual and cultural contexts of fin-de-siècle Central Europe. This paper demonstrates that Geschlecht und Charakter is an intensely personal analysis of intellectual, political, and cultural themes that were of central importance to contemporary Viennese intellectuals.