Abstract

This paper examines Christopher Peacocke’s implicit conceptions and their relation to conceptual identity. While Peacocke’s reliance on implicit conceptions marks a novel development in his views on concepts, it remains unclear whether he takes them to be constitutive of their associated concepts. I argue that this constitutive reading, which would align his view with conceptual role semantics, isn’t required and should be rejected. My argument turns on what I call the Phenomenon of Abandoned Principles—the fact that people can rationally reject principles they once took to be constitutive of a concept. This phenomenon, the flip-side of Peacocke’s Phenomenon of New Principles, is best explained by a model where the contentful states responsible for judgments about a concept’s application aren’t constitutive of that concept. I consider alternative models, including prototype theory and information-based semantics, showing that one can acknowledge tacit conceptions that guide our judgments without committing to the view that these conceptions are constitutive of conceptual content.