Abstract

In this introductory chapter to my collection of papers, Modal Matters, I present my tripartite account of reality. First, I endorse a plenitudinous Platonism: for every consistent mathematical theory, there is in reality a mathematical system in which the theory is true. Second, for any way of distributing fundamental qualitative properties over mathematical structures, there is a portion of reality that has that structure with fundamental properties distributed in that way; some of these portions of reality, when isolated, are the possible worlds. Third, there is a fundamental ontological distinction between those portions of reality that are absolutely actual, and those that are merely possible. In the course of developing this account of reality, I sketch my views on logic, mathematics, modality, qualitative character, and actuality. An austere Humeanism that rejects all primitive modality motivates and constrains my views.