Argues that the operating characteristics of perceiving and remembering provide a foundation for progress on detailing the processes through which knowledge is realized in real-time tasks and in detailing the processes of developmental change. Includes three examples to illustrate how forming developmental hypotheses in terms of perceiving and…

Examined whether spatial classification is discovered during play and if external products of play lead children to use space to represent similarity. Found through two experiments--a longitudinal study of four children's classification behaviors, and the examination of play behavior with two types of objects--that comparison of different kinds…

The hypothesis that overall-similarity relations structure both adults' and children's classifications of heterogeneous objects (objects that differ in a variety of ways) was supported in two experiments. When objects varied simultaneously on many dimensions, adults and children constructed classifications that maximized within-category similarity…

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…

Examined whether a holistic magnitude relation governs children's object comparisons. Objects varying on two dimensions of magnitude, size, and saturation were classified by three-, four-, and five-year-olds. Results indicated that younger children were sensitive to global magnitude as well as to overall similarity. (Author/BE)

Investigated the development of classificatory organization. Two experiments examined age differences in children's spontaneous extensions of a classification and a third examined children's extensions under hypothesis-testing instructions. (JMB)

Researched the possibility that four- to six-year-old children are competent and systematic classifiers, at least making classifications by overall similarity. In three experiments, young children classified various sets of multidimensional stimuli that could be organized into catagories by overall similarity or by diminsional attributes. Children…

Two studies explored the hypothesis that young children perceive integrally some stimuli that older children perceive separably. In both experiments, kindergarten, second- and fifth-grade children were required to classify sets of stimuli that varied in size and brightness. (SB)

Examines how reference points for the categorical interpretation of high and low (adjectives) were defined by three- to five-year-old children and adults. Shows categorical interpretations of relative terms to be complex dependent. (HOD)

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…

The contrast between holistic and differentiated perception of multidimensional stimuli is reconceptualized. Hypotheses about the experiential status of dimensions within holistic perception were tested as explanations of children's general perceptual mode and of adults' integral mode. Three levels of dimensional status are described. (Author/RD)