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…

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…

Clarifies features of Smith et al.'s attentional learning account of object naming, arguing that Booth and Waxman's findings address tenets not in the attentional learning account while not addressing one of the central tenets of the attentional learning account. Suggests that the debate about the nature of children's language and cognition would…