Features and beliefs in the mental representation of categories

Abstract

Simple concepts such as chair and bird are central to human cognition, but the nature of these mental representations is unclear. Accounts based on probabilistically associated features fail to account for certain observations about category membership judgments. On the other hand, the possibility that concepts consist of or even include defining features has received little empirical support. The work reported here argues that certain phenomena may not reflect the actual presence of defining features, but rather only the presence of a belief in such features. Further, concepts will not be uniform with respect to this belief: Some concepts will include a belief in defining features, but others will not. Five experiments explore these possibilities through two different experimental tasks based on judgments of sentence acceptability. Results support the idea that concepts include beliefs about the nature of the categories they represent, and that certain concepts (notably, many natural kind concepts) differ from others (notably, many common artifact concepts) in the nature of the beliefs held, even though defining features may not be explicitly represented in either.