When reasoning about a representation (e.g., a toy lion), children often engage in "iconic realism," whereby representations are reported to have properties of their real-life referents. The present studies examined an inverse difficulty that we dub "representational disregard": overlooking (i.e., disregarding) a…

It has been suggested that due to functional similarity, sortal object individuation might be a primordial form of psychological essentialism. For example, the relative independence of identity judgment from perceived surface features is a characteristic of essentialist reasoning. Also, infants engaging in sortal object individuation pay more…

How likely is the glass to break, given that it is heated? The present study asks questions such as this with or without the premise "if the glass is heated, it breaks." A reduced problem (question without premise) measures the statistical dependency (conditional probability) of an event to occur, given that another has occurred. Such…

Two experiments were conducted to determine if infants attribute false beliefs to others when tested with the violation-of-expectancy procedure. In Experiment 1, the false-belief task was administered to 14- and 18-month-old infants. The procedure was identical to the one used by Onishi and Baillargeon (2005), except that two transparent boxes…

This study investigated the development of the understanding of class inclusion in children age 5, 7, and 9 years, whose performance on a qualitative class-inference task assessing their appreciation of the transitive and asymmetrical nature of inclusive relations within the animal domain was compared with their ability to make quantitative…

Surface similarity generally promotes reasoning by analogy and physical similarity has been shown to have a powerful positive effect on very young children's use of a scale model as a source of information about another space. The research reported here investigated 2 1/2-year-old children's performance in an object retrieval task when asked to…

Interest in U-shaped development has itself undergone a U-shaped progression. Twenty-five years ago, interest in U-shaped development was high. This interest was evident at a 1978 conference in Tel Aviv on "U-shaped Behavioral Growth" that resulted in the publication of a book of the same title 4 years later (Strauss, 1982). The breadth…