Abstract

On the powerful qualities view, every fundamental property is both dispositional and qualitative. Identity theory is the standard account of the view, which makes the stronger claim that a property’s dispositionality and qualitativity are identical to each other, and identical to the property itself. Recent defences of the powerful qualities view have involved novel theories of powerful qualities which are not also variants of identity theory. Giannotti (Erkenntnis 86:603–621, 2021a) has suggested a novel theory of his own, the dual aspect account, which makes use of a particular notion of aspects. For Giannotti, dispositionality and qualitativity are each an aspect of a property, and an aspect is a property’s way of being. The importance of aspects is twofold. Firstly, by introducing aspects to identity theory, the theory becomes more precise. Secondly, aspects allow for a novel theory of powerful qualities, the dual aspect account, which maintains that dispositionality and qualitativity are aspects, but rejects the identity claim. Giannotti’s aim is to show that even if identity theory is false, the dual aspect account remains an available theory for advocates of powerful qualities. This paper will be a critical examination of Giannotti’s ideas. Firstly, I will clarify Giannotti’s notion of aspects, explaining how it involves a misunderstanding of supervenience, and why it does not offer the advantages that he claims it does. Secondly, in light of my discussion of aspects, I will argue that the dual aspect account lacks relative advantages over the compound view of powerful qualities.