From the beginning of the scientific revolution, scientists, philosophers, and laypersons have been concerned about the effects of knowledge on social relations. Although views differ about the details of this knowledge-society interface, most observers have understood that the kind of knowledge that emanates from establishedscience can indeed be quite powerful in practice. In exploring both the nature of race science discourse and selected features of the practical context within which it resonates effectively, the authors' investigationsof this field and its contribution (...) to the Holocaust represent an effort to specify some of the things that make knowledge powerful. (shrink)