Necessity is both metaphysically and epistemologically troubling. Metaphysically, it is hard to see how it is that necessity gets bestowed on a proposition. One way of making necessity metaphysically and epistemologically tractable is to see it as less a feature of the world itself and more a feature of the way in which we describe the world. Conventionalism about modality is one way of doing this. Conventions, argued Quine, cannot create truths. Conventions can only transform one truth to another. A problem for Crude Conventionalism is that it seems that the necessary truths outrun any plausible list of the analytic truths. The modal features of the substance themselves are a matter of how the world is. Instead of explaining away modal features of the world, all that seems to have been accomplished is that we’ve said there is only water if there are modal features of the world.