The idea of using genetic engineering to enhance human beings scares a lot of people. For example, at a 2006 meeting called by the American Association for the Advancement of Sciences, Richard Hayes, the executive director of the left-leaning Center for Bioethics and Society, testified that “enhancement technologies would quickly be adopted by the most privileged, with the clear intent of widening the divisions that separate them and their progeny from the rest of the human species.” Deploying such enhancement technologies would “deepen genetic and biological inequality among individuals,” exacerbating “tendencies towards xenophobia, racism and warfare.” Hayes concluded that allowing...