Abstract

Though modern non-cognitivists in ethics characteristically believe that values are irreducible to facts, they nevertheless believe that values are determined by facts, viz., those specified in functionalist, explanatory theories of the evolutionary origin of morality. The present paper probes the consistency of this position. The conventionalist theories of Hume and Harman are examined, and are seen not to establish a tight determinative reduction of values to facts. This result is illustrated by reference to recent theories of the sociobiological mechanisms involved in moral evolution. Though explanatory theories have linguistic implications,exaggerated in Harman's linguistic form of social relativism, there is also failure to establish the semantic reductionism which non-cognitivists reject under the rubric of ethical naturalism. It is concluded that explanatory forms of naturalism, the best of which is a functionalist-utilitarian account, are compatible with the fact/value distinction.