Abstract

The argument is that on moore's analysis of normative language, which is both nonnaturalistic and cognitivistic, one must adopt two distinct criteria of truth. and that any theory which fundamentally assumes two distinct and independent types of truth need not be committed to a logical dualism, that there are some sets of deductive rules homomorphic to the rules of propositional logic which validate certain arguments the premises of which may be true in different ways, and that a system having these properties is a normal alethic modal logic