Expansionism and Mereological Universalism

Mereological universalists, according to whom every plurality of entities has a fusion, usually claim that most quantifications are restricted to ordinary entities. However, there is no evidence that our usual quantifications over ordinary objects are restricted. In this article I explore an alternative way of reconciling Mereological Universalism with our usual quantifications. I resort to a modest form of ontological expansionism and to the so-called interpretational modalities. Quantifications over ordinary objects are the initial stages of the expansion. From these initial stages, expansions can proceed upwards (fusions of entities in the domain of quantification are added), downwards (parts of entities in the domain are added), and sidewards (entities which are mereologically disjoint from the entities in the domain are added). These expansions are driven by a variety of epistemic and pragmatic reasons and raise different kinds of problems. At each stage, a modalized version of Mereological Universalism is true. By contrast, only at some especially rich stages, standard, non-modalized Mereological Universalism is true as well. Among these especially rich stages, there is a final, metaphysically pre-eminent stage of mereological plenitude. In the last part of the article I discuss some problems and limitations of expansionism