Do children understand desires before they understand beliefs? A comparison of 3-years-olds' grasp of incompatible desires, competitive games and false beliefs

A long-standing dispute in theory of mind research concerns the development of understanding different kinds of propositional attitudes. The asymmetry view suggests that children understand conative attitudes (e.g., desires) before they understand cognitive attitudes (e.g., beliefs). The symmetry view suggests that notions of cognitive and conative attitudes develop simultaneously. Relevant studies to date have produced inconsistent results, yet with different methods and dependent measures. To test between the two accounts more systematically, we thus combined different forms of desire tasks (incompatible desires and competition) with different forms of measurement (verbal ascription and active choice) in a single design. Additionally, children’s performance in the desire tasks was compared to their false-belief understanding. Results revealed that 3-year-olds were better at ascribing desires than at ascribing beliefs for both desire tasks whereas they had difficulties actively choosing the more desired option in the competition task. The present findings thus favor the asymmetry theory.