Three studies investigated the influence of principle-based inferences and unprincipled similarity relations on new category learning by three- to six-year-old children. Results indicated that categorization into newly learned categories may activate self-initiated, principle-based reasoning in young children, suggesting that spontaneous…

Responds to four commentaries on the article by Jones and Smith in this issue. Suggests that the comments derive from the possibility that stable concepts might not exist and from the difficulty of imagining what cognition could be without represented concepts. Discusses traditional approaches to stability and variability, and considers what…

Three experiments used an object-examining task to explore infants' attention to function and form-function correlations. The results suggested a developmental progression from attending only to the form of objects, to attending to form and function as separate properties, and finally to attending to the relationship between form and function.…

Reviews current research on children's concepts and categories that reflects a growing consensus that nonperceptual knowledge is central to concepts and determines category membership, whereas perceptual knowledge is peripheral in concepts and only a rough guide to category membership. Argues that there is no compelling basis in theory or in data…

Comments on the article by Jones and Smith in this issue. Responds to the theses that perceptual information is as much at the core of concepts as is nonperceptual information and that concepts are not represented as such but are computed on-line when needed. Presents a view of the relationship between perception and conceptual knowledge…

Comments on the article by Jones and Smith in this issue. Describes a program of research that demonstrates the important influence of perception on the structure of concepts. Proposes that both perceptual and nonperceptual information are important to conceptual structure throughout the continuum of knowledge acquisition and that perception is a…

Comments on the article by Jones and Smith in this issue. Outlines different perspectives from which the issue of conceptual development is approached, elaborating on the functions concepts serve and variations in those functions. Notes points of agreement with the perceptual knowledge view and offers comments on the research supporting the…

This commentary on the article by Jones and Smith in this issue examines whether coherent conceptual cores exist in long-term memory; abstract propositions constitute conceptual cores; concepts in long-term memory control behavior; and the primary purpose of developing and using concepts is to taxonomize the environment. (TJQ)

Two experiments examined preschoolers' and adults' relative reliance on visual and verbal information in identification of animals and machines. Findings include both children and adults can use either visual or verbal cues in categorization, and a stricter definition is used in identifying animals. Results suggest that a perceptual to conceptual…

Study reports data on the acquisition of knowledge about astronomy in children from India, and the cosmological models they construct. Found that Indian children's cosmologies honor a variety of implicit assumptions governing the construction of initial cosmological models and that folk models are also incorporated to provide a psychologically…

Four studies examined preschoolers' use of the cue of action initiation to infer another's desired goal. Found that differences in action initiation play an increasingly important role in 3-year-olds' mentalistic explanations of action, and that this development may be related to other critical changes occurring in their developing theory of mind.…

Examined developmental differences in evidence evaluation skills among school children, non-college educated adults, and college students, utilizing plant growth variables. Found that children were more strongly influenced by prior beliefs and missing data than were the two adult groups. Age and educational differences were found in the…