Unifying Kinds without Hylemorphism

Abstract David Oderberg has recently extended classical Aristotelian-Thomistic hylemorphism beyond traditional substance ontology to analyse linguistic, ethical and political kinds. Whilst this project identifies important structural features of these domains, I argue that his hylemorphic apparatus is unnecessary. Drawing on the ‘Unification Principle’ (UP) account of natural kinds, I demonstrate that Oderberg’s insights can be captured more parsimoniously and with greater empirical constraint. I further argue that the mind-independence criterion for natural kinds applies to the unification principles themselves rather than to the kinds directly, allowing this framework to accommodate social and linguistic entities. The UP approach thus handles Oderberg’s case studies effectively whilst avoiding the metaphysical commitments and structural problems associated with hylemorphism.