Children's developing knowledge about diversity in thought

Although children acquire some impressive knowledge about the mind during the preschool years, a growing body of research suggests that there are several important insights about the mind that are not understood by children until after these years. This research explores one insight about the mind that is hypothesized to be part of this post-preschool theory-of-mind development, namely, the belief that two people's trains of thought will differ even when prompted by the same visual stimulus. Study 1 investigated older preschoolers', fourth graders', and adults' understanding of this aspect of the mind by asking them to predict whether characters would have the same or different thoughts, and then subsequently to explain why. Results suggested that although the two older groups had a rather sophisticated understanding of differences in thought, preschoolers largely failed to recognize that people who saw the same thing would have different subsequent trains of thoughts. Study 2 aimed to replicate and extend these findings in two ways: (1) to see whether additional information would make the task easier for younger children; and (2) to chart the development of this understanding during the early elementary school years. Although preschoolers were shown to have some rudimentary insight into diversity, this study showed that their understanding of this aspect of thinking is limited in many ways, and improves during the elementary school years. Study 3 assessed preschoolers' understanding using a slightly modified procedure in which children were asked to provide possible thoughts for two characters who both saw the same object. Again, preschoolers demonstrated some beginning, but nonetheless limited, understanding of diversity in thinking. Taken together, these studies suggest that the recognition that people usually have different trains of thoughts even when they see the same thing develops during the elementary school years, and possibly beyond. The recognition of such diversity undoubtedly provides children with insight in the mental lives of others and with a more complete understanding of what it means to be a unique individual. As such, it marks an important social-cognitive advance.