Children's knowledge of the presuppositions of know and other cognitive verbs

Abstract

This study investigated the development of knowledge about the presuppositions of cognitive verbs that take sentential complements. The verbs included factives, which presuppose the truth of their complements, and nonfactives, which carry no such presupposition. Three tasks assessed children's ability to (a) assign truth values to complements according to the presuppositions of the main verbs; (b) select verbs to describe people's mental states; and (c) state the presuppositions of the verbs in definitions. The results indicated that the presuppositions of the factives know, forget, and remember and the nonfactive think are not learned until age 4. Believe, which has factive and nonfactive properties, is mastered after age 7. The children's performance differed across tasks due to variations in processing requirements.