Proceedings of the Annual Meeting of the Cognitive Science Society

When deciding how to act in new situations, we expect agents todraw on relevant prior experiences. This expectation underliesmany of our mental-state inferences, allowing us to infer agents’prior knowledge from their current actions. Do children sharethis expectation, and use it to infer others’ epistemic states? InExperiment 1, we find that five- and six-year-olds (but not four-year-olds) attribute additional knowledge to agents whose priorexperiences cannot explain their success. In Experiment 2, wefind that six-year-olds (but not younger children) also attributegreater knowledge to agents whose prior experience cannotexplain their failure. We show that by age five or six, childrenexpect ignorant agents’ beliefs (and therefore their actions) to beguided by their prior knowledge. This work adds to a growingbody of research suggesting that, while infants can representmental states, the ability to infer mental states continues todevelop throughout early childhood.