The Principles of Conventionality and Contrast in Word Learning: An Empirical Examination.

In Study 1, 4-year-olds avoided 2 names for an object when exposed to a common or a proper noun in a puppet's presence or to a common noun in a puppet's absence, but not when exposed to a proper noun in a puppet's absence. In Study 2, 3-year-olds avoided 2 names for an object when the requester for the referent of a second label in a different language was bilingual and present during naming, but not when the speaker was bilingual but absent or monolingual. Study 3 followed up on the results of the first 2 studies. When children could assume that the puppet knew the name the experimenter used, they inferred that the puppet's use of a different name implied a different referential intent.