Abstract

Philosophers have historically been concerned with concepts and their analysis, and in recent decades psychologists have also begun to speculate on what kinds of structures concepts might be. I take concepts to satisfy three core desiderata: they are mental representations, they are the constituents of thoughts, and they are centrally employed in categorization. There are four major theories of concepts currently in play: definitionism, prototype and exemplar theory, the 'theory theory', and conceptual atomism. I survey these theories and argue that none of them adequately satisfies all three of the core properties. The reasons for these failures are principled, and generalize to many other positions that share their assumptions. Concepts do not form a unitary psychological natural kind. I propose taking a pluralist view of concepts. Conceptual representations are adaptively constructed and used by a set of processes that vary with elements of the task, subject, domain, and wider context