In taking properties to have powerful or dispositional essences, dispositionalism is primed to provide an account of causation. This paper lays out a challenge confronting the dispositionalist’s ability to account for how powers causally interact with one another so as to bring about collective results. The challenge, here labeled the “interaction gap,” is raised for two competing kinds of approaches to dispositional interaction: contribution combinationist and mutual manifestationist. After carefully highlighting and testing potential resources for closing the interaction gap, it (...) is concluded that the mutual manifestationist approach holds a significant advantage. In turn, the importance of the interaction gap itself is highlighted. While powers prime an ontology to yield an account of causation, how far that account can actually go depends on the metaphysical details of one’s view of powers and their causal interaction. (shrink)

Impure Eliminativism about Categories is the idea that ontological categories are not wholly eliminable insofar as they have epistemic value to understand the nature of ordinary and scientific objects. From the perspective of Impure Eliminativism, different criticisms have been addressed to substantialist approaches in metaphysics and, in particular, to John Heil’s substance-mode two-category ontology. The aim of this paper is to contribute to this critical project by extending its scope to C. B. Martin’s substantialism. The thesis I defend is that (...) Martin’s substratum-trope two-category ontology satisfies the elimination criterion of Impure Eliminativism for ontological categories because either it is inconsistent or else it supplies a non-exhaustive and non-exclusive categorization of ordinary and scientific objects and their properties. First, I introduce Impure Eliminativism and its novel elimination criterion for ontological categories, and I survey recent criticisms of substantialism from that perspective. Second, I show that nothing satisfies Martin’s definition of substratum in a way that is consistent with Martin’s view on tropes. Third, I note that the attempts to avoid the inconsistency make the categorization supplied by Martin’s ontology either non-exhaustive or non-exclusive. I then conclude that Martin’s substratum-trope categorial system should be eliminated in accordance with the criterion of categorial elimination of Impure Eliminativism. (shrink)