Expressions Related To Knowledge And Belief In Children'S Speech

Children develop certain abilities related to Theory of Mind reasoning, particularly concerning the False-belief Task, between the ages of 3 and 5. This paper investigates whether there is a corresponding change in the frequency of linguistic expressions related to knowledge and belief produced by children around these ages. Automated corpus analysis techniques are used to tag each expression related to knowledge and belief in a large corpus of transcripts of speech from normally developing English-learning children. Results indicate that the frequency of expressions related to knowledge and belief increases steadily from the beginning of children's language production. Tracking of individual concepts related to knowledge and belief indicates that there are no clear qualitative changes in the set of concepts that are expressed by children of different ages. The implications for the relationship between language and the development of Theory of Mind reasoning abilities in children are discussed.