Young children's understanding of "remember" and "forget".

3 studies examined young children's understanding that if one "remembers" or "forgot," one must have known at a prior time. In Study 1, 4-year-olds but not 3-year-olds understood the prior knowledge component of "forgot"; both groups understood that a character with prior knowledge was "gonna remember." Study 2 controlled for the possibility that good performance on "remember" might be due to a simple association of remembering with knowledge. A significant number of 4-year-olds but not 3-year-olds understood that when 2 characters currently knew, the one with prior knowledge remembered, and that when neither character currently knew, the one with prior knowledge forgot. Study 3 made prior knowledge more salient by making the remembered or forgotten item visible to the subjects throughout. 4-year-olds performed near ceiling on both verbs, whereas 3-year-olds' performance did not differ from chance. The results are discussed in relation to children's developing understanding of the mind.