Category-based induction is a hallmark of mature cognition; however, little is known about its origins. This study evaluated the hypothesis that category-based induction is related to semantic development. Computational studies suggest that early on there is little differentiation among concepts, but learning and development lead to increased…

Executive function mechanisms underpinning language-related effects on theory of mind understanding were examined in a sample of 165 preschoolers. Verbal labels were manipulated to identify relevant perspectives on an explicit false belief task. In Experiment 1 with 4-year-olds (N = 74), false belief reasoning was superior in the fully and…

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…

Individuals can infer what others are likely to know by clustering knowledge according to common goals, common topics, or common underlying principles. Although young children are sensitive to underlying principles, that manner of clustering might not prevail when other viable means are presented. Two studies examined how a sample of 256 children…

A total of 12 three, four, five, seven, and nine year olds and 12 adult control subjects were asked 20 questions about two exemplars of each of 16 categories of animate beings and inanimate objects. Children's responses indicated that animism is not a pervasive phenomenon and does not appear to be the most primitive mode of conceptualization.…

Visual preference procedures were used to investigate development of perceptually based subordinate-level categorization in 3- to 7-month-old infants. Experiments 1 and 2 demonstrated that 3- to 4-month-olds did not form category representations for photographic exemplars of subordinate-level classes of cats and dogs (i.e., Siamese vs. Tabby,…

The normative rule began to predominate at age 10 and was the only rule employed by 13-year-olds. In contrast, almost all 7-year-olds simplified the equalization task to an ordinal level. Four different nonalgebraic rules were identified. Neither young children's tendency to simplify nor older children's capacity to quantify could be detected in…

Preschool children judged the larger of pairs of stimuli. Three-year olds responded with above-chance accuracy, while 4- and 5-year olds defined "big" as "tall." (ST)

Infants of 14 months of age demonstrated significantly improved understanding of containment as a result of a training intervention in which they played with cans and tubes in their homes for a month. After training, their test scores were similar to those of untrained 20-month-old children. (RH)

Children's thinking about diversity of belief in 4 realms morality, taste, facts, and ambiguous facts was examined. Ninety-six participants (ages 5, 7, and 9) were interviewed about beliefs different from their own that were endorsed by characters with different status; their judgments of relativism, tolerance, and disagreeing persons were…

Four experiments investigated three- and four-year-old children's knowledge of projective size-distance and projective shape-orientation relationships. Results indicated that preschool children's understanding of these relationships seems at least partly cognitive rather than wholly perceptive, providing further evidence for the acquisition of…

The purpose of present experiments with subjects approximately three, five, and seven years of age was to provide additional evidence for the obviousness of the generative transmission principle and to provide initial evidence for the secondary principles of absence and facility. Empirical support was found for each of these selection principles,…

The importance of actions, results, and instruments in the development of verb concepts was examined in four studies. Studies are discussed in terms of theory and research on conceptual development, word learning strategies, and the semantic organization of nouns and verbs. (PCB)

Administration of a placement task to 66 preschool and grade school children revealed that the concept of higher/lower was understood earlier than above/below, which in turn was understood earlier than rising/falling. Within each pair of terms, the one referring to upness was comprehended earlier. (Author/JMB)