Abstract
Much of children's knowledge is derived not from their direct experiences with the environment but rather from the input of others. However, until recently, the focus in studies of concept development was primarily on children's knowledge, with relatively little attention paid to the nature of the input. The past 10 years have seen an important shift in focus. This article reviews this approach, by examining the nature of the input and the nature of the learner, to shed light on early conceptual learning. These findings argue against the simple notion that conceptual development is either supplied by the environment or innately specified, and instead demonstrate how the two work together. The implications for how children reconcile competing belief systems are also discussed.