Ontology of Powers
John Heil
Our conference organizers have posed the question, ‘which ontology does the assumption of irreducible powers suggest or even presuppose?’ In particular we have been asked:
| (1) | How should powers be ontologically categorized? Do they need bearers? If so, to which ontological category might such bearers belong? | ||
| (2) | Does dispositional realism favour an ontology of substances, or events, or tropes, &c? | ||
| (3) | Which account of persistence should dispositionalists endorse? | ||
| (4) | Are there irreducible powers only in the microphysical realm or also in the macrophysical realm? |
I accept what I take to be the organizers’ presumption, the idea that ontology is a package deal. An ontology is not something to be constructed by bolting together off-the-shelf parts in the way a hobbyist might assemble a home computer from components purchased at Radio Shack. The components of an ontology owe their integrity to their place in the system.
I sketch an account of powers situated within a substance–property ontology. Substance and property are, as I see it, correlative notions: substances are various ways, properties are ways substances are; every substance is some way or other, every way is a way some substance is. What substances do or would do depends on their properties and properties of substances with which they interact.
Properties, on such a view, are powers, powerful ways substances are. Properties are not purely powers, however: properties are powerful qualities. Properties are qualities the identity of which depends on how they would manifest themselves with particular kinds of reciprocal partner.
A conception of this kind provides sufficient resources to make sense of modality and causation in a decidedly non-Humean manner. Powers can serve as truthmakers for various modal truths. Causation, understood as the mutual manifestation of powers, is revealed to be a kind of internal relation. With this ontological picture in play, it is possible to provide systematic answers to the questions posed above.
