New conceptions of learning, analogy, and capacity have fundamentally changed scientists' view of cognitive development. New conceptions of learning help to explain how representations of the world are acquired. New models of analogical reasoning have suggested that logical inferences are often made by mapping a problem into a mental model, or schema, induced from ordinary life experience. A model of analogical reasoning provides a basis for understanding children's limitations in cognitive capacity, and specifies changes in the nature of children's cognitive representations over time that explain phenomena previously attributed to developmental stages. The concepts children understand, and the strategies they develop based on their understanding, depend on the complexity of the representations they construct. Parallel Distributed Processing (PDP), a model of cognitive processing, explains why the number of dimensions, or independent items of information required to represent a concept, that can be processed in parallel is limited. The PDP model provides an account of the effect of the complexity of a concept on children's cognitive performance. In this model, cognitive growth depends on four main factors: (1) learning and induction; (2) conceptual chunking; (3) serial processing strategies; and (4) the development of the ability to represent concepts of higher dimensionality. A list of 39 references is attached. (MM)