Cross-race friendships can promote the development of positive racial attitudes, yet they are relatively uncommon and decline with age. In an effort to further our understanding of the extent to which children expect cross-race friendships to occur, we examined 4- to 6-year-olds' (and adults') use of race when predicting other children's…

These studies examined the role of ontological beliefs about category boundaries in early categorization. Study 1 found that preschool-age children (N = 48, aged 3-4 years old) have domain-specific beliefs about the meaning of category boundaries; children judged the boundaries of natural kind categories (animal species, human gender) as discrete…

The goal of the present study was to explore domain differences in young children's expectations about the structure of animal and artifact categories. We examined 5-year-olds' and adults' use of category-referring generic noun phrases (e.g., "Birds fly") about novel animals and artifacts. The same stimuli served as both animals and artifacts;…

Psychological essentialism is the belief that some internal, unseen essence or force determines the common outward appearances and behaviors of category members. We investigated whether reasoning about transplants of bodily elements showed evidence of essentialist thinking. Both Americans and Indians endorsed the possibility of transplants…

Previous research indicates that the ontological status that adults attribute to categories varies systematically by domain. For example, adults view distinctions between different animal species as natural and objective, but view distinctions between different kinds of furniture as more conventionalized and subjective. The present work (N=435;…

Three studies examined the co-existence of natural and supernatural explanations for illness and disease transmission, from a developmental perspective. The participants (5-, 7-, 11-, and 15-year-olds and adults; N = 366) were drawn from 2 Sesotho-speaking South African communities, where Western biomedical and traditional healing frameworks were…

The present studies examined beliefs concerning the impact of psychosocial factors in the transmission of contagious illness, injuries, and disgust. In Studies 1 and 2, participants ranging from preschoolers through adults judged the likelihood that a character would get sick (or injured) after being contaminated by another individual who was…

Essentialism is the belief that certain characteristics (of individuals or categories) may be relatively stable, unchanging, likely to be present at birth, and biologically based. The current studies examined how different essentialist beliefs interrelate. For example, does thinking that a property is innate imply that the property cannot be…

Two studies compared how preschoolers through fifth graders and adults reasoned about psychogenic bodily reactions such as stress-induced headaches. Results supported a developmental path: younger children view psychogenic bodily responses as wholly physical, but with age, view them as both physical and psychological. (Author/KB)

Three experiments investigated use of vitalistic explanations for biological phenomena by 5- and 10-year-olds and by adults. Results replicated the original Japanese finding of vitalistic thinking among English-speaking 5-year-olds, identified the more active component of vitalism as a belief in the transfer of energy during biological processes,…

Four studies with kindergarten through fifth graders and adults examined the development of reasoning about the origins of psychological traits. Results suggested an age-related increase in the tendency to distinguish among different psychological traits, and that over time, individuals come to believe that psychological traits are determined…