In its most elaborately articulated form racism is an array of theoretical views about the epistemic clarity and human import of the practice of individuating human populations in terms of their presumed biological descent. In this form the term can refer with some precision, and largely independently of context, to a quite specific body of beliefs. In far more diffuse and far less theoretical forms, however, and in forms which are also far more widely distributed in human history, it can and does refer just as readily to the highlighting of distinctions which are certainly at least as much cultural as they are genetic, and which are inextricably located in a context of more or less intimate and painful confrontation between human groups. In this second form there cannot in principle be anything comparably determinate for the term racism to refer to.

The main claim that I wish to advance is that it is the second and vaguer guise of racism, and not the first and more theoretically precise guise, which has made it a topic of urgent political importance throughout much of human history and which still makes it of such pressing significance today. This may at first hearing seem paradoxical since the most dramatic and ghastly single impact of the category of race upon human history, the Final Solution, certainly involved the adoption of an array of putatively scientific beliefs about human biology and is scarcely intelligible, even in principle, as anything other than an attempt to enact some of the practical implications of these beliefs for those who belonged amongst the genetically approved segment of the German population.