Recent philosophical work has disclosed a host of problems in our apparently natural ways of classifying things. The contemporary classification of certain groups as "minorities" exemplifies some of these problems. I argue that these classifications are arbitrary and misleading. Through examining several of the most significant ethical moments in the history of modern medicine, including the thought and conduct of Nazi physicians, the Tuskegee study, Beecher's questioning of post-war research practices and Percival's enunciation of a universalist ethic for physicians, I make a case against racial and ethnic classification of patients. Such classifications can play a destructive role in determining the sort of health care which minorities receive. Embracing them, even with the intent of improving the lot of those who do not fare well in the present health care environment, is subversive of the egalitarian stance which has been central to medical ethics since Hippocrates.