Recognizing information as evidence is central to the development of scientific reasoning. When does information about an event come to be treated as evidence relevant to explaining the event? We asked whether this was increasingly likely to happen when an explanation becomes available that can incorporate both the event and the information into a…

We investigated whether the tendency to imitate or emulate is influenced by the availability of causal information, and the amount of information available in a display. Three and 5-year-old children were shown by either a live or video model how to obtain a reward from either a clear or an opaque puzzle box. Some of the actions in the sequence…

One important characteristic of rational action is that intentions should be consistent with beliefs. Two studies examined whether three year olds understand belief constraints on intention. In both studies, subjects' understanding of unfulfilled intentions was excellent and significantly better than their understanding of false beliefs, but…

Results of a study with children ages three to eight indicated that children's understanding of the concept of surprise changes between three and five years of age. Younger children employed a principle of desirability, whereas older children employed principles of belief violation, indicating that children's understanding of the concept of…

This study examined developmental changes in concept formation, rule switching, and perseverative behaviors of children in the WCST by altering visual features of the test and using a new test score--the "zigzag" error score--which shows the number of shifts made between two incorrect concepts or rules. Instead of the original four 3-dimensional…

Adapted Keil's predictability method to examine adults' and preschoolers' conceptions of numbers, focusing on the ontological distinction between numbers and sets of objects. Found that children, like adults, attribute spatial-arrangement properties to collections much more than to numbers, although both are considered to have quantitative…

Two experiments examined preschoolers' and adults' relative reliance on visual and verbal information in identification of animals and machines. Findings include both children and adults can use either visual or verbal cues in categorization, and a stricter definition is used in identifying animals. Results suggest that a perceptual to conceptual…

Tested children with apparatus that dropped balls through clear or opaque interwoven tubes. Found that older children could solve configurations with greater number of tubes than younger children. Success with clear tubes did not transfer to opaque tubes. Significantly, errors were consistently directed to location directly below ball's last seen…