Flanagan (1991) was the first contemporary philosopher to suggest that a modularity of morals hypothesis (MMH) was worth consideration by cognitive science. There is now a serious empirically informed proposal that moral competence is best explained in terms of moral modules-evolutionarily ancient, fast-acting, automatic reactions to particular sociomoral experiences (Haidt & Joseph, 2007). MMH fleshes out an idea nascent in Aristotle, Mencius, and Darwin. We discuss the evidence for MMH, specifically an ancient version, “Mencian Moral Modularity,” which claims four innate modules, and “Social Intuitionist Modularity,” which claims five innate modules. We compare these two moral modularity models, discuss whether the postulated modules are best conceived as perceptual/Fodorian or emotional/Darwinian, and consider whether assuming MMH true has any normative ethical consequences whatsoever. The discussion of MMH reconnects cognitive science with normative ethics in a way that involves the reassertion of the “is-ought” problem. We explain in a new way what this problem is and why it would not yield. The reason does not involve the logic of “ought,” but rather the plasticity of human nature and the realistic options to “grow” and “do” human nature in multifarious legitimate ways.