Since the 1890s Theodor Kaes (1852-1913), then alienist at the Hamburg asylum Friedrichsberg, began to explore myeloarchitectonics. He was particularly interested in dementia paralytica and the fibers of the association system. Following Paul Flechsig (1847-1929) and Theodor Meynert (1833-1892), Kaes read class and ethnical hierarchies into myelinated fibers and so could "decipher" the hierarchical structure of Wilhelminian society in the brain. Since 1908 he was in a fierce dispute with Korbinian Brodmann (1868-1918) about the correctness of his measurements. The article depicts the life and work of Kaes against the backdrop of the development of German neurosciences around 1900.