Naming,Saying, and Structure

It is commonplace for philosophers to distinguish mere truths from truths that perspicuously represent the world's structure. According to a popular view, the perspicuous truths are supposed to be metaphysically revelatory and to play an important role in the accounts of law‐hood, confirmation, and linguistic interpretation. Yet, there is no consensus about how to characterize this distinction. I examine strategies developed by Lewis and by Sider in his Writing the Book of the World which purport to explain this distinction in terms of vocabulary: the truths that represent the world perspicuously have better, joint‐carving vocabulary. I argue that the distinction between a perspicuous and mere truth concerns both the vocabulary of the sentence and its grammar. I then show that the collective motivations for distinguishing perspicuous from mere truths do not allow Lewis and Sider to properly impose constraints on grammar.