Jürgen Habermas has argued against prenatal genetic interventions used to influence traits on the grounds that only biogenetic contingency in the conception of children preserves the conditions that make the presumption of moral equality possible. This argument fails for a number of reasons. The contingency that Habermas points to as the condition of moral equality is an artifact of evolutionary contingency and not inviolable in itself. Moreover, as a precedent for genetic interventions, parents and society already affect children's traits, which is to say there is moral precedent for influencing the traits of descendants. A veil-of-ignorance methodology can also be used to justify prenatal interventions through its method of advance consent and its preservation of the contingency of human identities in a moral sense. In any case, the selection of children's traits does not undermine the prospects of authoring a life since their future remains just as contingent morally as if no trait had been selected. Ironically, the prospect of preserving human beings as they are – to counteract genetic drift – might even require interventions to preserve the ability to author a life in a moral sense. In light of these analyses, Habermas' concerns about prenatal genetic interventions cannot succeed as objections to their practice as a matter of principle; the merits of these interventions must be evaluated individually.