At the onset of Life, Liberty and the Defense of Dignity, Leon Kass gives us a status report on where we stand today: “Human nature itself lies on the operating table, ready for alteration, for eugenic and psychic ‘enhancement,’ for wholesale redesign. In leading laboratories, academic and industrial, new creators are confidently amassing their powers and quietly honing their skills. For anyone who cares about preserving our humanity, the time has come for paying...