Abstract
Kit Fine and Gideon Rosen propose to define constitutive essence in terms of ground-theoretic notions and some form of consequential essence. But we think that the Fine–Rosen proposal is a mistake. On the Fine–Rosen proposal, constitutive essence ends up including properties that, on the central notion of essence (what Fine calls ‘the notion of essence which is of central importance to the metaphysics of identity’), are necessary but not essential. This is because consequential essence is (roughly) closed under logical consequence, and the ability of logical consequence to add properties to an object’s consequential essence outstrips the ability of ground-theoretic notions, as used in the Fine–Rosen proposal, to take those properties out. The necessary-but-not-essential properties that, on the Fine–Rosen proposal, end up in constitutive essence include the sorts of necessary-but-not-essential properties that, others have noted, end up in consequential essence.