I. INTRODUCTION: RECONCEPTUALIZING THE NATURE OF CHILDREN’S CONCEPTUAL STRUCTURES AND THEIR DELOVEPMENT IN MIDDLE CHILDHOOD

Abstract

Robbie CaseThe first theorist to articulate a general theory of intellectual development in the post-Darwinian era was James Mark Baldwin (1894/1968).According to Baldwin's theory, children's thought progressed through a sequence of four universal stages, which he termed the stages of "sensorimotor," "quasi-logical," "logical," and "hyperlogical" thought.In any given stage, Baldwin believed that new experience was "assimilated" to the existing form of thought, much in the manner that the hody assimilates food.He saw transition from one form of thought to the next as driven hy "accommodation," a process by which existing habits or schemata are broken down and then reorganized into new and more adaptive patterns.Although Baldwin was the first to articulate a general theory of cognitive development, it was Piaget's (1960, 1970) reworking of Baldwin's theory that had the greatest impact on the field.The most important feature that Piaget added to Baldwin's theory was the notion of a "logical structure," that is. a coherent set of logical operations that can he applied to any domain of human activity and to which any cognitive task in the domain must ultimately be assimilated.Piaget hypothesized that the form of children's operational structures is different at different stages of their development and that this gives their thought at each stage a unique character.To highlight the importance of these operational structures, he relabeled Baldwin's second and third stages of development, calling them the stages of "preoperational" and "operational" thought, respectively.He also divided the stage of operational thought into the "concrete" and "formal" periods.Piaget spent a good deal of effort explicating the process that Baldwin had labeled "accommodation": that is, tbe process by which low-level opera-