This chapter argues that Gottingen physician and naturalist Johann Friedrich Blumenbach's classification of human varieties can be fully understood only when this aspect of his work is put in perspective. In his scientific publications he emphasized again and again that the so-called racial differences within the human species are superficial and transient, rendering any classification more or less arbitrary. With respect to the first aspect, the question of how to properly classify the human genus had been of scientific interest since the founder of modern biological systematics, Carl Linnaeus, had included humans in his Systema Naturae and had recognized two human species: Homo sapiens and Homo troglodytes. Stephen Jay Gould would probably not have objected to reconstruction of Blumenbach's general argument regarding the unity of the human species. In his chapter on "racial geometry" he arrived at a similar conclusion, praising Blumenbach for his egalitarian ideas, and emphasizing that he was "the man most committed to human unity".