The identifica-tion of eugenic fitness with racial, national, or class traits assumes that these traits are genetic and that the so-called higher groups are really superior. For reasons which are discussed, the genetic nature of such traits has not been demonstrated. The traits of the so-called superior groups, even if genetic, are not necessarily fitter in an evolutionary sense, for they are often negatively correlated with evolutionary survival. Nor are they necessarily better in an ethical sense, for rising in the social scale may result from unethical conduct. Even if good eugenical standards were agreed upon, there is danger for various reasons that in practice superior individuals would not actually be chosen for propagation. In the past the evolutionary improvement of the human race has been facilitated by its division into small communities, so that new traits could spread more easily; and by the forcing of superior individuals into the lower classes, where they were more prolific. The disappearance of these conditions, however desirable from other points of view, raises eugenic difficulties. The equalization of opportunity is a necessary but not a sufficient condition for a deliberate program of scientific eugenics, since the causes that lead to the selection of inferior individuals will persist as long as there is competition for power or for the approbation of one''s fellow-men.