In this paper, I directly oppose Nietzsche ’s endorsement of a morality of breeding to all forms of comparative, positive eugenics: the use of genetic selection to introduce positive improvement in individuals or the species, based on negatively or comparatively defined traits. I begin by explaining Nietzsche ’s contrast between two broad categories of morality: breeding and taming. I argue that the ethical dangers of positive eugenics are grounded in their status as forms of taming, which preserves positively evaluated character traits and types through the active de-selection of negatively evaluated ones. The morality of taming is not a form of selection, but de-selection: the production of counter or anti-traits and types. Consequently, in its attempt to improve humanity, it tends necessarily toward violence as the elimination of de-selected forms of human life. In contrast, Nietzsche ’s morality of breeding selects traits and types by protecting them from de-selection—specifically, by attacking moral ideas, values, and practices designed to eliminate them. It tends not towards the destruction but preservation of types; its negativity targets not life but the ideas that disable, disempower, and eradicate forms of life. I argue, further, that the fundamental ethical difference between breeding and taming, and so between Nietzschean morality and eugenics, is found in their attitudes toward the natural world. The violence of eugenics as taming is grounded in its status as anti-natural, while Nietzsche ’s morality of breeding resists violence through its foundational affirmation of the conditions and limitations of the natural world: its resolute moral naturalism. Finally, I apply my interpretation of breeding and taming to two cases of comparative, positive eugenics: the historical case of racial eugenics and the so-called “designer baby” case in contemporary liberal eugenics. Nietzsche must condemn both as forms of the anti-natural morality of taming, to which the morality of breeding is diametrically opposed.