Three experiments addressed the relative importance of original function and current function in artifact categorization. Subjects were asked to judge whether an artifact that was made for one purpose (e.g. making tea) and was currently being used for another purpose (e.g. watering flowers) was a teapot or a watering can. Experiment 1 replicated the finding by Hall (1995) (unpublished manuscript) that adults rely on the original function of an artifact over a current function in their kind judgments. Experiments 2 and 3 revealed that whereas the kind judgments of 6-year-olds, like those of adults, patterned with the original function, those of 4-year-olds did not. Four-year-olds were influenced by the order in which the functions were mentioned in the story. Further, in their justifications 6-year-olds and adults referred to the origin of the objects, whereas 4-year-olds virtually never did. We conclude that 6-year-olds have begun to organize their understanding of artifacts around the notion of original function, and that 4-year-olds have not. The data are discussed as they bear on children's understanding of the design stance (Dennett, D. C. (1987). The intentional stance. Cambridge,

This research monograph examines the potential of constructivist learning environments for developing prerequisites of expert knowledge during university studies. Drawing on recent theories of the development of expert knowledge and on the constructivist view of learning, an experiment was conducted in an educational psychology course. The primary purpose of the study was to compare the learning outcomes of students who studied the course material in a constructivist learning environment with those of students who learned it under traditional teaching and studying conditions. Students in the constructivist learning environment acquired more diversi"ed knowledge. In addition, a theory will be presented about what actually changes when conceptual change occurs. # 1999 Elsevier Science Ltd. All rights reserved.

Experiments investigated whether infants infer that a hidden, freely moving object will move continuously and smoothly. Infants aged 6 and 10 months, like the $-month-old infants in previous experiments, inferred that the object’s path would be connected and unobstructed, in accord with the principle of continuity. In contrast, 4- and 6-month-old infants did not appear to infer that the object’s path would be smooth, in accord with the principle of inertia. At 8 and 10 months, knowledge of inertia appeared to be emerging but remained weaker than knowledge of continuity. These findings are consistent with the view that common sense knowledge of physical objects develops by enrichment around constant core principles. The core knowledge thesis Human adults generally can predict how the things around them will behave. When a ball rolls from view on a table, for example, adults infer that it will continue to exist and to move on a connected path, that it will move smoothly in the absence of obstacles or surface irregularities, that it will rebound from or Supported by grants from NSF (BNS-8613390) and NIH (HD-23103) and by a fellowship to E.S.S. from the John Simon Guggenheim Memorial Foundation. We thank Frank Keil for comments and

Several earlier investigations found that teaching standard textbook physics causes only moderate change in qualitative understanding. Manyinvestigations have tried to explain why teaching textbook physics results in so little learning of qualitativephysics. In contrast, we examined cases where learning did occur and tried to understand them, hoping that this might help us to understand how to support such learning. We developed computerized simulation models of both qualitative, conceptual problem solving and quantitative problem solving and used them to assess changes in students' qualitative knowledge as they learned textbook physics. In many cases, qualitative knowledge has been acquired on the basis of information explicitly presented in the textbook. However, we also found cases where learning of qualitativephysics took place on the basis of information only implicitly addressed in the instruction. Even more important, in various cases this newly acquired qualitative knowledge led to a less frequent use of incorrect qualitative pre-knowledge. This suggests that successfull students did not only learn what has been explicitly presented in the instruction. Rather, they did also learn by deriving and constructing information left implicit in the instruction, relating this information to their pre-knowledge and possibly re#ning and modifying their pre-knowledge in those cases where con#icts became aware.

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People learn quickly when reasoning about causal relationships, making inferences from limited data and avoiding spurious inferences. Efficient learning depends on abstract knowledge, which is often domain or context specific, and much of it must be learned. While such knowledge effects are well documented, little is known about exactly how we acquire knowledge that constrains learning. This work focuses on knowledge of the functional form of causal relationships; there are many kinds of relationships that can apply between causes and their effects, and knowledge of the form such a relationship takes is important in order to quickly identify the real causes of an observed effect. We developed a hierarchical Bayesian model of the acquisition of knowledge of the functional form of causal relationships and tested it in five experimental studies, considering disjunctive and conjunctive relationships, failure rates, and cross-domain effects. The Bayesian model accurately predicted human judgments and outperformed several alternative models.

Sortal concepts, lexicalized as count nouns in languages with a count/mass distinction, pro, criteria for individuation and numerical identity. This paper examines Quine's and Piaget's cla that babies and young children lack the logical resources to represent sortal concepts. Evidence is marshalled against the Quine/Piaget position, in favor of a view that even yo infants represent at least one sortal concept, physical object, which provides spatiotemp4 criteria for individuation and identity. Evidence is also provided that babies below 11 month age may not represent more specific sortals such as cup, animal, bottle, or book. Rather, t may conceptualize these entities in a way closely related to Quine's hypothesis. 1

Abstract: In this paper we describe a way of looking at how people learn from computer interfaces. In particular, we describe the concept of a socially relevant representation, or a representation of social context information (as opposed to domain knowledge information). We describe known or hypothesized mechanisms by which such representations might facilitate learning, and discuss implications for the design of knowledge media. Keywords: Computer-Supported Collaborative Learning (CSCL), human-computer interaction, cognition, instructional design, knowledge media, representations. Introduction: context as a clue to understanding This paper explores the role that representations of social context information can play in learning. Consider the following experience. Hoadley was a graduate student in an interdisciplinary doctoral program in science education. The first year students came from many different backgrounds in the sciences, and were preparing for an exam to cover readings from a first-year seminar in cognition and education. For many, the papers

Consider two individuals, John and Mary, who each possess a number of concepts. How can we determine that John and Mary both have a concept of, say, Horse? John and Mary may not have exactly the same knowledge of horses, but it is important to be able to place their horse concepts into correspondence with one another, if only so that we can say things like, “Mary’s concept of horse is much more sophisticated than John’s. ” Concepts should be public in the sense that they can be possessed by more than one person (Fodor, 1998; Fodor & Lepore, 1992), and for this to be the possible, we must be able to determine correspondences, or translations, between two individuals ’ concepts. There have been two major approaches in cognitive science to conceptual meaning that could potentially provide a solution to finding translations between conceptual systems. According to an “external grounding” account, concepts ’ meanings depend on their connection to the external world (this account is more thoroughly defined in the next section). By this account, the concept Horse means what it does because our perceptual apparatus can identify features that characterize horses. According to what we will call a “Conceptual web ” account, concepts ’ meanings depend on their connections to each other. By this account, Horse’s meaning depends on Gallop, Domesticated, and Quadruped, and in turn, these concepts depend on other concepts, including Horse (Quine & Ullian, 1970). In this chapter, we will first present a brief tour of some of the main proponents of conceptual web and external grounding accounts of conceptual meaning. Then, we will describe a computer algorithm that translates between conceptual systems. The initial goal of this computational work is to show how translating across systems is possible using only withinsystem relations, as is predicted by a conceptual web account. However, the subsequent goal is to show how the synthesis of external and internal information can dramatically improve translation. This work suggests that the external grounding and conceptual web accounts should not be

Preferential looking experiments investigated 5- and LX-month-old infants’ perception and understanding of the motions of a shadow that appeared to be cast by a ball upon a box. When all the surfaces within the display were sta-tionary, infants looked reliably longer when the shadow moved than when the shadow was stationary, indicating that they detected the shadow and its motion. In further experiments, however, infants ’ looking was not consistent with a sensitivity to the shadow’s natural motion: They looked longer at nat-ural events in which the shadow moved with the ball or remained at rest under the moving box than at unnatural events in which the shadow moved with the box or remained at rest under the moving ball. These findings suggest that infants overextend to shadows a principle that applies to material objects: Objects move together if and only if they are in contact. In a final experiment, infants were habituated to a moving shadow that repeatedly violated one aspect of the contact principle. In a subsequent test they failed to infer that the shadow would violate another aspect of the contact principle. Instead, they appeared to suspend all predictions concerning the behavior of the shadow. Because environments are made visible by illumination, and because most sources of illumination are directional, shadows are among the most common This research was supported by NIH grant R37 HD 23 103 to ESS and by fellowships from NSF and from the Fyssen Foundation to GAV. Experiments 1-3 were submitted in partial fulfilment of an honors thesis by JSR to the Cornell College Scholars Program. We thank Gavin Huntley-Fenner and Susan Carey for valuable comments and criticism, Deborah King for help with many aspects of the research, and Ed Snyder for building the apparatus.