According to the identity version of spacetime supersubstantivalism, material objects are numerically identical to spacetime regions. While the view has been commended for its parsimony and concordance with physics, it has not properly been assessed in light of the metaphysics of properties. The present essay fills this void by discerning several subspecies of identity supersubstantivalism, corresponding to various property ontologies. Finding them all wanting, the essay develops and defends a novel brand of supersubstantivalism based on the trope ontology. On this (...) view, here dubbed ‘supertropestantivalism’, regions are pluralities of geometrically and topologically alike tropes, some of which bundle together as material objects. The resulting picture is not itself an identity version of supersubstantivalism, but it retains the originally attractive features of the identity version while avoiding the shortcomings of competing ontologies. (shrink)

The four principal competing substance ontologies are substratum theory, bundle theory, primitive substance theory, and hylomorphism. Both historically and in the recent literature, most arguments pertaining to these four theories have been developed under the assumption that only one of them can be true. However there is room in this debate for various forms of pluralism: mild pluralism here refers to the view that while only one of these four theories is true of our world, there is at least one (...) other possible world in which a different substance ontology obtains; moderate pluralism refers to the view that while only one of these four theories is true of our world, there is at least one other possible world in which multiple substance ontologies obtain ; and extreme pluralism refers to the view that our own actual world contains substances belonging to different substance ontologies. In this paper I lay out a novel argument for a version of extreme pluralism. (shrink)