Sorting and acting with objects in early childhood: an exploration of the use of causal cues

Three experiments investigated young children’s ability to use a causal property, making a machine light up and play music, to sort objects together (sorting task), and then to predict how to make the machine work (action task). The results show that the performance of 30-month-old children is guided in both tasks by the causal properties of the objects. This suggests that causal information is used to categorize objects even in a task that does not involve naming. The causal interpretation of the results is supported by data showing that non-causal temporal association and perceptual prominence cannot account for the results. Finally, 36-month-olds, but not 30-month-olds, sorted objects together on the basis of a “negative” feature, namely, the fact that they lacked a particular causal property. © 2003 Elsevier Science Inc. All rights reserved.