Sortal concepts, object individuation, and language.

Cognitive science is an interdisciplinary enterprise. This review highlights how the philosophical notion of a 'sortal'--a concept that provides principles of individuation and principles of identity - has been introduced into cognitive developmental psychology. Although the notion 'sortal' originated in metaphysics, importing it into the cognitive sciences has bridged a gap between philosophical and psychological discussions of concepts and has generated a fruitful and productive research enterprise. As I review here, the sortal concept has inspired several lines of empirical work in the past decade, including the study of object individuation; object identification; the relationship between language and acquisition of kind concepts; the representational capacities of non-human primates; object-based attention and cognitive architecture; and the relationship between kind concepts and individual concepts.