  In explaining and defining race, Du Bois participates in a turn-of-the-century conversation in German philosophy about the subjects and methods that distinguish the human from the natural sciences—that is, the Geisteswissenschaften from the Naturwissenschaften. Responding to Auguste Comte’s and J.S. Mill’s efforts to reform the human sciences on the model of the natural sciences, German scholars addressed a variety of questions as to the human sciences’ cognitive aims, possible methodological autonomy, and dependence on psychology. When Du Bois arrived in Berlin in 1892, the conversation was well underway and had already benefitted from the significant contributions of Wilhelm Dilthey and Wilhelm Wundt several years earlier. During the 1890s there were further contributions, in particular the writings of Georg Simmel, Wilhelm Windelband, and Heinrich Rickert. Although Du Bois initially presented “The Conservation of Races” as an address to the American Negro Academy, the essay was a significant addition to the German debate, for it marks Du Bois’s turn from the Naturwissenschaften to the Geisteswissenschaften to explain the differences between races and to conceptualize racial  identities.[8]