Theory of mind and epistemological development: the relation between children's second-order false-belief understanding and their ability to reason about evidence

The study investigates the hypothesis that children's ability to attribute second-order beliefs facilitates their understanding of evidence, as seen in the ability to distinguish between causes and reasons. Seventy-four children 5-7 yr old were given belief and evidence tests. The belief tests assessed their ability to represent and reason from second-order false-beliefs, and the evidence tests assessed their ability to distinguish between the cause of a situation and a person's reason for believing it. The relation between performance on the two tests was determined, taking into account general language and non-verbal reasoning abilities. Results show that performance on the belief test and on the evidence part of the evidence test improved significantly over the age range, and that a significant proportion of variance in the evidence test scores is accounted for by second-order false-belief understanding, over and above that accounted for by general language and non-verbal abilities. The argument is made that second-order false-belief understanding is fundamental to children's epistemological development, underlying not just their understanding of evidence, but also their understanding of inference and truth. (C) 2002 Elsevier Science Ltd. All rights reserved.