Children's early understanding of false belief

We investigated 3-year-olds' understanding of the representational capability of the mind by examining whether they would acknowledge that they had entertained a wrong belief. As in previous studies, children very often judged that they had believed a Smarties tube contained pencils when these were revealed as the true content, even though they had stated "Smarties" before the tube had been opened. Under another condition, when the tube was first presented, children mailed a picture into a postbox of what they thought was inside (Smarties). When asked "When you posted your picture, what did you think was in here (the tube)?" the great majority of children answered correctly with "Smarties". Additionally, children nearly always stated that the posted card displayed a picture of Smarties, and that the tube really contained pencils. On the traditional task, children may give the wrong answer because they are biased to make judgments about belief states on the basis of known physical reality. The posting task made it possible for children simultaneously to focus on physical reality and acknowledge false belief.