Speaking Your Mind: Expression in Locke's Theory of Language

There is a tension between John Locke’s awareness of the fundamental importance of a shared public language and the manner in which his theorizing appears limited to offering a psychologistic account of the idiolects of individual speakers. I argue that a correct understanding of Locke’s central notion of signification can resolve this tension. I start by examining a long standing objection to Locke’s view, according to which his theory of meaning systematically gets the subject matter of our discourse wrong, by making our ideas the meanings of our words. By examining Locke’s definition of “truth”, I show that Lockean signification is an expression relation, rather than a descriptive or referential relation. Consequently, the sense in which our words signify our ideas is roughly that our utterances advertise our otherwise undisclosed mental lives to each other. While this resolves one aspect of the public/private tension, I close with a brief discussion of the remaining tension, and the role for normative constraints on signification to play in generating a genuinely shared public language.