Children's Selective Trust in Promises.

There has been extensive research into the development of selective trust in testimony, but little is known about the development of selective trust in promises. The present research investigates children's (N = 264) selective trust in others' promises to help. In Study 1, 6-year-olds selectively trusted speakers who had previously kept a promise. In Study 2, 5-year-olds displayed selective trust for speakers who had previously kept a prosocial promise (promise to help). In Study 3, 5-year-olds trusted a speaker, who kept a prosocial promise, over a helper. These data suggest that from the age of 5 children show selective trust in others' promises using prosociality, promise keeping, or both to inform their judgments.