The original uploader was Algebraa at German Wikipedia. (Original text: Photograph unbekannt) · Public domain

In 1903, months before his death by suicide at 23, published Sex and Character, a sprawling and controversial treatise on gender and identity that became an unlikely influence on major figures of early twentieth-century thought — Ludwig Wittgenstein cited it directly, and it shaped James Joyce by way of Weininger's later essay Über die letzten Dinge. The book's swift notoriety after his death turned Weininger into one of fin-de-siècle Vienna's most-discussed and most-disputed intellectual figures.