Abstract
Let us distinguish two kinds of contingentism: entity contingentism and metaphysical contingentism. Here, I use ‘entity’ very broadly to include anything over which we can quantify—objects (abstract and concrete), properties, and relations. Then entity contingentism about some entity, E, is the view that E exists contingently: that is, that E exists in some possible worlds and not in others. By contrast, entity necessitarianism about E is the view that E exists of necessity: that is, that E exists in all possible worlds. We can distinguish two views: global entity contingentism and global entity necessitarianism. Global entity contingentism is the view that for any possible E, E exists contingently. Global entity necessitarianism is the view that for any possible E, E exists necessarily.
While entity contingentism and entity necessitarianism are views about the modal status of entities, metaphysical contingentism and necessitarianism are views about the modal status of metaphysical principles. Metaphysical contingentism about some metaphysical principle, P, is the view that P is contingent: it is true in some worlds, and false in others. Metaphysical necessitarianism about P is the view that P is necessary: either P is true in every world, or false in every world. We can then distinguish two views: global metaphysical contingentism and global metaphysical necessitarianism. Global metaphysical contingentism is the view that for any internally coherent metaphysical principle P, P is contingent: P is true in some worlds and false in others. Global metaphysical necessitarianism is the view that for any internally coherent metaphysical principle, P, P is necessary: it is either true in every world, or false in every world.
This chapter principally focuses on metaphysical rather than entity contingentism, though §2 briefly discusses the latter. As we will see, (§2), both global entity contingentism and global entity necessitarianism are controversial views, and most philosophers fall somewhere between these two extremes, holding that some, but not all, entities exist necessarily—a view we can call entity moderatism. By contrast, global metaphysical necessitarianism has, until recently, largely been the default view. It is only recently that some philosophers have argued that we should be metaphysical contingentists about at least some metaphysical principles—a view we can call metaphysical moderatism. §3 considers why global metaphysical necessitarianism has hitherto been so persuasive, then evaluates (§3.1) some arguments for the view before considering more recent arguments in favour of the contingency of (at least some) metaphysical principles (§3.2).