Ernst Haeckel and Emil du Bois-Reymond were the most prominent champions of Darwin in Germany. This essay compares their contributions to popularizing the theory of evolution, drawing special attention to the neglected figure of du Bois-Reymond as a spokesman for a world devoid of natural purpose. It suggests that the historiography of the German reception of Darwin’s theory needs to be reassessed in the light of du Bois-Reymond’s Lucretian outlook.