An object's mental representation includes not just visible attributes but also its nonvisible history. The present studies tested whether preschoolers seek subtle indicators of an object's history, such as a mark acquired during its handling. Five studies with 169 children 3-5 years of age and 97 college students found that children (like adults)…

Two studies (N = 456) compared the development of concepts of animal species and human gender, using a switched-at-birth reasoning task. Younger children (5- and 6-year-olds) treated animal species and human gender as equivalent; they made similar levels of category-based inferences and endorsed similar explanations for development in these 2…

Trait attribution is central to people's naive theories of people and their actions. Previous developmental research indicates that young children are poor at predicting behaviors from past trait-relevant behaviors. We propose that the cognitive process of behavior-to-behavior predictions consists of two component processes: (1) behavior-to-trait…

Research on children's knowledge of illnesses has largely concentrated on studying how children reason about common innocuous diseases. It is also important to uncover how children reason about more severe diseases, such as cancer, to be able to treat and communicate with children diagnosed with this disease. Several aspects of prevalent childhood…

Generic sentences (such as "Birds lay eggs") are important in that they refer to kinds (e.g., birds as a group) rather than individuals (e.g., the birds in the henhouse). The present set of studies examined aspects of how generic nouns are understood by English speakers. Adults and children (4- and 5-year-olds) were presented with scenarios about…

This study tests the firm distinction children are said to make between living and nonliving kinds. Three, 4-, and 5-year-old children and adults reasoned about whether items that varied on 3 dimensions (alive, face, behavior) had a range of properties (biological, psychological, perceptual, artifact, novel, proper names). Findings demonstrate…

Comments on the article by Jones and Smith in this issue. Outlines different perspectives from which the issue of conceptual development is approached, elaborating on the functions concepts serve and variations in those functions. Notes points of agreement with the perceptual knowledge view and offers comments on the research supporting the…

Reviews selected research on children's early formation of categories. Finds sophistication in how children group objects and think about those groupings. Notes findings related to type of grouping (thematic or taxonomic), multiple classifications, overgeneralization, the role of background knowledge on classification abilities, the…