Examines language effects in class-inclusion performance with 224 children ages 3 through 12 by comparing the standard Piagetian question with two alternate question forms. Overall, the findings were inconsistent with the Piagetian assertion that logical inability produces errors in comparing subclasses; inclusion performance was a function of…

Preschool children were given a memory task that required repeating a list of animal names and a sentence imitation task. Results confirmed a relationship between word span and language imitation in younger preschool children and the notion of a memory constraint on early spontaneous language. Increasing mastery of linguistic rules appeared to…

Examines the development of children's understanding of the difference between "want" and "need" in two different experiments. The first experiment required the children to respond verbally in choosing between the two concepts; the second required them to give an object to one of two characters who had made a request using…