The Physicist and the Poet: In 1801, J. Ritter discovered UV radiation, but the inspiration for this came from Goethe. In February 1801, the young, romantic experimental physicist Johann Ritter discovered UV radiation in Jena. This groundbreaking achievement was not solely his work: he built upon Goethe's optics, utilized his scientific method, shared his goals, and received important insights from him. The day after his discovery, Ritter visited Goethe and demonstrated the experiment to him—such was his gratitude to the poet. In his study, Olaf Müller narrates the fascinating journey to the discovery of ultraviolet light. He begins in 1791 with Goethe's protest against Newton's color theory. Shortly thereafter, the poet had everything in place to be the first to observe the effects of UV light, but he narrowly missed the discovery. After meeting Ritter in 1798, both inspired each other to further their research. The tumultuous history of their collaboration up to Ritter's tragic death in 1810 is presented here for the first time as a comprehensive double biography—including Ritter's legacy in Faust and Elective Affinities. We must revise our image of Goethe: one of the great physicists around 1800 took his optics seriously.