King develops a syntax-based account of propositions based on the idea that propositional unity is grounded in the syntactic structure of the sentence. This account faces two objections: a Benacerraf objection and a grain-size objection. I argue that the syntax-based account survives both objections, as they have been put forward in the existing literature. I go on to show, however, that King equivocates between two distinct notions of ‘propositional structure’ when explaining his account. Once the confusion is resolved, it is clear that the syntax-based account suffers from both Benacerraf and grain-size problems after all. I conclude by showing that King's account can be revised to avoid these problems, but only if it abandons its motivating idea that it is syntax that unifies the proposition.