Two experiments examined young children's use of the familiarity principle when learning language. Found that even 2-year-olds successfully identified the referent of a proper name as the individual with whom the speaker was familiar. However, only 5-year-olds reliably succeeded at determining the individual with whom the speaker was familiar…

Examined the use by children of the Novel Name-Nameless Category principle, under the framework that lexical principles are acquired in a developmental sequence. Results indicated that the particular principle was not available at the start of lexical acquisition but that exhaustive categorization ability and a vocabulary spurt occur…