Moral Realism, Moral Relativism and Moral Rules (A Compatibility Argument)

Relativism and realism are often held to be in conflict. It is not obvious what the exact nature of the conflict is supposed to be, because it is not obvious what the two doctrines amount to. But that there is some kind of conflict between moral realism and moral relativism is evidenced by the fact that some take moral relativism to be the straightforward denial of moral realism. David Brink, for example, baldly states that ‘Moral relativism is usually understood as a denial of realism or objectivity about ethics’ (Brink 1989, 43). This definitional thesis is wrong. Even so, in the case of morality at least the tension between the two seems clear enough. Why? The moral realist holds inter alia that there are objective truths in the moral domain, and further that these objective truths are not mere human artefacts, but are backed up by special kinds of facts. The moral relativist, on the other hand, claims that judgements of right and wrong, permissibility and obligation, and so on, are in an important sense socially constructed; that they are human artefacts, perhaps of a very sophisticated sort; that they depend on the existence of human institutions, agreements and conventions, tacit or explicit, and vary from one set of such institutions and agreements to another. For example, Richard Boyd writes that ‘Moral realism . . . contrasts with views according to which moral principles are largely a reflection of social constructs or conventions’ (Boyd 1988, 182). Mark Platts (characterizing relativism): ‘Moral judgments are partly the result of conventions which could have been and in some places are, otherwise’ (Platts 1988, 286). And finally, Gilbert Harman: ‘Moral relativism denies that there are universal basic moral demands and says that different people are subject to different basic moral demands depending on the social customs, practices, conventions, values and principles that they accept’ (Harman 1989, 363). I will show that these apparently incompatible theses could both be true: that is, that realism and relativism are logically compatible in the moral domain. The compatibility argument I offer does not exploit the incommensurability of rival conceptual frameworks. Nor does it turn on our limited epistemic access to, and hence disagreement over, the alleged