I agree with this from Dan Little. Putting it here to save and come to.
This impulse towards moral realism is a problem. Moral realism and scientific realism are not analogous. There is no philosophical or theological method that will resolve moral questions into an unquestionable foundation or set of universal moral truths. Neither Kantianism, nor Aristotelianism, nor utilitarianism, nor traditional religious systems have the capacity to establish universal and unquestionable moral conclusions. The impulse towards moral realism has the perilous possibility of morphing into a dogmatic view of morality that substitutes one's own convictions for eternal moral truths. In my view, this is farfetched and ultimately implies an unreflective dogmatism about values. Fortunately there is a better and more modest position available that derives from the same pragmatist origins that are inspiring other advances in critical realism.
The better approach is based on a coherence epistemology. This approach is explicitly anti-realist when it comes to moral values. Ethical reasoning always has to do with conversation, disagreement, and sometimes progress. Moral practices have social reality, to be sure; but there are no "moral facts" consisting of moral principles and values that are beyond the possibility of further rational debate. This approach to moral theory emphasizes corrigibility and pragmatic debate about ends, means, and values. It converges with coherence epistemology along the lines of Quine and Rawls; it deliberately replaces a foundationalist approach to moral thinking with a corrigible ongoing series of discussions by moral equals. This allows for an epistemology based on dialogue, and it comes out of the pragmatist tradition.