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…

This study examines the development of children's ability to reason about proportions that involve either discrete entities or continuous amounts. Six-, 8- and 10-year olds were presented with a proportional reasoning task in the context of a game involving probability. Although all age groups failed when proportions involved discrete quantities,…