 This idea, that assertion is the expression of belief, has a longer history, going back to at least Kant. How should one understand the idea of expressing here? It is natural to think of a belief state, that is, a mental state of the speaker, as causally co-responsible for the making of the assertion. The speaker has a belief and wants to communicate it, which motivates an assertoric utterance. But what about the cases when the speaker does not believe what he asserts? Can we still say, even of insincere assertions, that they express belief? If so, in what sense?