Abstract

This dissertation defends and develops the thesis that some instances, or tokens, of dispositional properties are pure. A pure disposition has no causal basis in any further properties beyond the disposition. A causal basis typically consists of some set of properties underlying a disposition that enables the disposition to manifest when stimulated in the appropriate circumstances. For example, a vase is fragile because it is disposed to break when a hammer or other suitable object strikes it, where the causal basis for fragility is the underlying micro-structure of the vase. Moreover, micro-structural properties of the vase seem to anchor the continuous existence of the vase’s fragility when the vase is not actually breaking. In contrast to the neo-Humean metaphysical assumption that any disposition requires a causal basis in further properties, as in the example of fragility, the Pure Dispositions Thesis denies this. This dissertation achieves four goals. First, it defends the Pure Dispositions Thesis from notable objections: the Powers Regress Argument, the Insufficient Causal Basis Argument, the Argument from the Identity Thesis, and the Argument from Spatial Occupation. Second, it evaluates several theories of the continuous existence of pure dispositions, and argues that some pure dispositions are self-grounded via a minimally sufficient occurrence of their own power. Third, it presents two arguments that some pure dispositions are extrinsically grounded, the Argument from the Higgs Field and the Argument from Priority Monism, and deflects numerous objections to those arguments. Finally, it develops and defends an account of systems of pure dispositions, arguing that a pure dispositional system may generate higher-level categorical and dispositional properties by way of an emergence mechanism involving the union of two pure dispositions