VI—Four Grades of Modal Naturalism

How, if at all, can scientific progress improve our view of the modal facts? According to rationalist approaches to modal epistemology, science has no substantive role: a priori reflection reveals the structure of modal space, and a posteriori science merely locates us within that modal space, by identifying the actual properties and structures instantiated at our world. According to modal naturalist approaches, science provides evidence about the structure of the underlying modal space. In this paper I distinguish four versions of modal naturalism, with science playing an increasingly robust evidential role, and discuss their plausibility.