The Emperor's New Metaphysics of Powers

This paper argues that the new metaphysics of powers, also known as dispositional essentialism or causal structuralism, is an illusory metaphysics. I argue for this in the following way. I begin by distinguishing three fundamental ways of seeing how facts of physical modality — facts about physical necessitation and possibility, causation, disposition, and chance — are grounded in the world. The first way, call it the first degree, is that the actual world or all worlds, in their entirety, are the source of physical modality. Humeanism is the best known such approach, but there are other less well-known approaches. The second way, the second degree, is that the source of physical modality lies in certain second-order facts, involving a relation between universals. Armstrong’s necessitarianism and other views are second-degree views. The third way, the third degree, holds that properties themselves are the source of physical modality. This is the powers view. I examine four ways of developing the third degree: relational constitution, graph-theoretic structuralism, dispositional roles, and powerful qualities. All these ways are either incoherent, or just disguised versions of the first-degree. The new metaphysics of powers is illusory. With the collapse of the third degree, the second degree, the necessitarian view of law, collapses as well. I end the paper with some reflections on the first degree, on the problem of explaining necessary connections between distinct existences, and on the dim prospects of holist ontology.