One of the most malevolent characteristics of racist thought is that it never produces new knowledge. It seems able to merely reformulate and refigure itself in multiple but static assertions. It has no referent in the material world; like the concept of black blood or white blood or blue blood, it is designed to construct artificial borders and maintain them against all reason and all evidence to the contrary. And while racist thought and language have an almost unmitigated force in political and social life, the realm of racial difference has been allowed an intellectual weight to which it has no claim. It is truly a realm that is no realm at all — an all-consuming vacancy that is both common and strange.