Cognitive Development, 7, 273-285 (1992) The Foundations of Conceptual Thought in Infancy Jean M. Mandler University of California, San Diego and MRC Cognitive Development Unit, London An overview of a theory of the foundation of conceptual thought in infancy is presented. The theory proposes that perceptual analysis redescribes perceptual information into meanings that form the basis of an accessible conceptual system. These early meanings are represented in the form of image-schemas that abstract certain aspects of the spatial structure of objects and their movements in space. Image-schemas allow infants to form concepts such as animate and inanimate objects, agents, and containers. It is proposed that this form of representation serves a number of functions, including providing a vehicle for simple inferential and analogical thought, enabling the imitation of actions of others, and providing a conceptual basis for the acquisition of the relational aspects of language. How and when do infants first begin to conceptualize or think about the world? Since the work of Piaget, most psychologists have assumed that infants know only what they perceive and (in some sense) what they do. Infants are said to have perceptual categories and sensorimotor routines, but not yet to have con- cepts about things (e.g., Quinn & Eimas, 1986). Still. by 2 years of age a conceptual system has clearly become established. What has happened in the interim? How does the infant transform itself from a sensorimotor creature to a conceptual one’? Piaget. of course. had a theory about this transition, but it has seemed to me for some time that his approach to the onset of conceptual repre- sentation cannot be correct as it stands. It overlooks some crucial aspects that are required for a theory of concept formation, and is difficult to reconcile with current evidence suggesting that conceptual representation begins much earlier than the theory allows. In Piaget’s (1952) theory. for the first year and a half of the sensorimotor stage infants do not yet have the capacity to conceptualize (represent) the world. The development of the symbolic function is said to be a long, slow process that requires the speeding up and “interiorization” of sensorimotor schemas in the Preparation of this article was supported in part hy NSF rcsenrch grant BNS89- 19035. Thanks to Annette Karmilolf-Smith for helpful comments. Correspondence and requests for reprints should be sent IO Jean M. Mandler. Department of Cognitive Science. University of California. San Diego. La Jolla. CA 92093-0515. Manuscript received October 17, 1991; revision accepted February 10, 1992 273