According to a thesis I call the linguistic assumption, the structure of language is a guide to the fundamental nature of reality. It is deployed in the metaphysical debate over the nature of time. In that debate, it is more radical than the Sapir-Whorf hypothesis, and should be rejected. A weak interpretation of the Sapir-Whorf hypothesis makes the empirical claim that speakers of different languages experience, perceive, or think about aspects of the world differently. I survey recent experimental evidence that supports this hypothesis which, I argue, gives us further reason to reject the linguistic assumption.