ABSTRACT
Developmental psychologists tend to study deception in children for two reasons. First and foremost, the topic is addressed within the realm of theory of mind development. And second, researchers are interested in deception within the context of moral development. In the latter case they are mostly restricted to the verbal form of deception: lying. To some extent both approaches are related. A functional theory of mind implies the acknowledgement that people act on their own subjective representations of a situation, and that these representations might differ from person to person, depending on the personal beliefs and desires concerning that situation (Wellman, 1990). Only infants consider their own desires as universally present in all people. But around the age of 2 years they start to acknowledge that not all people like that banana as much as they do. The subjectivity of beliefs seems somewhat more problematic. Therefore, passing a so-called “false belief test” is usually taken as the criterion for a functional theory of mind. Wimmer and Perner (1983) created the original version of such a test. They showed the children a little puppet play, in which they witness how the puppet Maxi lays his bar of chocolate on the kitchen table. He wants to save it for later. Then he leaves the scene in order to play outside with his friends. Next, his mother enters the stage and puts the chocolate in the cupboard. Maxi returns home hungry and wants to eat his chocolate. Before he enters the kitchen the play stops. The experimenter then asks the child: Where do you think Maxi will look for his chocolate? Young children will answer on the basis of their own knowledge: in the cupboard. But by the age of 4 years
children normally realize that Maxi does not know anything about his mother’s intervention and will act on his own (false) belief state. He will look for his chocolate on the place where he left it: the kitchen table. This insight seems critical for lying (Chandler & Hala, 1991). It is only when we are aware that people act on their own beliefs that we may try to manipulate them by offering them a false belief on purpose.
