Ehrenfels aimed at a recuperation of a “natural sexual morality”, which would preserve and advance the healthy constitution of a species, as opposed to the cultural sexual morality of his time, which would instead corrupt it (Ehrenfels 1907, 8). This could be effected by recognizing that the main biological function of the sexual drive, namely reproduction, is not the only one. Sexuality also serves selection, not in the sense of natural selection as survival of the fittest, but selection aimed at ensuring reproduction by the best, leading to the progressive improvement of the species (Ehrenfels 1907, 9 ff.). This selection is the first and foremost function of male sex drive, which is why Ehrenfels speaks of “virile selection” (Ehrenfels 1907, 79, compare Dickinson 2002, 258). Since according to Ehrenfels males represent the active sex, not just among humans, but “in the entire bisexual animal kingdom”, and the females’ sex drive is only operative as a response to the males’, the male sex drive is the biologically more important one, and hence the basis for re-establishing the natural sexual morality.