Abstract

Concepts are widely agreed to be the basic constituents of thought. Amongst philosophers and psychologists, however, the question of how concepts are structured has been a longstanding problem and a locus of disagreement. I draw on recent work describing how representational content is ascribed to populations of neurons to develop a novel solution to this problem. Because disputes over the structure of concepts often reflect divergent explanatory goals, I begin by arguing for a set of six criteria that a good theory ought to accommodate. These criteria address philosophical concerns related to content, reference, scope, publicity, and compositionality, and psychological concerns related to categorization phenomena and neural plausibility. Next, I evaluate a number of existing theoretical approaches in relation to these six criteria. I consider classical views that identify concepts with definitions, similarity-based views that identify concepts with prototypes or exemplars, theory-based views that identify concepts with explanatory schemas, and atomistic views that identify concepts with unstructured mental symbols that enter into law-like relations with their referents. I conclude that none of these accounts can satisfactorily accommodate all of the criteria. I then describe the theory of representational content that I employ to motivate a novel account of concept structure. I briefly defend this theory against competitors, and I describe how it can be scaled from the level of basic perceptual representations to the level of highly complex conceptual representations. On the basis of this description, I contend that concepts are structured dynamically through sets of transformations of single source representation, and that the content of a given concept specifies the set of potential transformations it can enter into. I conclude by demonstrating that the ability of this account to meet all of the criteria introduced beforehand. I consider objections to my views throughout.