If we cannot find a way to interpret the utterances and other behaviour of a creature as revealing a set of beliefs largely consistent and true by our standards, we have no reason to count that creature as rational, as having beliefs, or as saying anything.

Mental events such as perceivings, rememberings, decisions, and actions resist capture in the net of physical theory.

Nothing in the world, no object or event, would be true or false if there were not thinking creatures.

Even if someone knew the entire physical history of the world, and every mental event were identical with a physical, it would notfollow that he could predict or explain a single mental event (so described, of course).

Conceptual relativism is a heady and exotic doctrine, or would be if we could make good sense of it. The trouble is, as so often in philosophy, it is hard to improve intelligibility while retaining the excitement.

There is no such thing as a language, not if a language is anything like what many philosophers and linguists have supposed. Thereis therefore no such thing to be learned, mastered, or born with. We must give up the idea of a clearly defined shared structure which language-users acquire and then apply to cases.