1994 年 42 巻 3 号 p. 261-269
This study examined the flexibility of conceptual knowledge in classifying natural common objects. In experiment 1, coneptual classification behavior in children aged 4, 5, and 7 was investigated by triadic technique and free sorting method which have been used in previous research. The results indicated there was no significant increase in conceptual classification with age but slightly increasing tendency. In Experiment 2, in contrast to the experimental paradigm of previous research, the demand of classification bases were clarified and changed by each trial. Classification bases consisted of conceptual, thematic, and perceptual relation between objects. Subjects were asked to classify the objects according to the demanded relation which was shown by exemplars. Seven-year-olds produced more appropriate responses to the demand of the conceptual and perceptual relation than 4-and 5-year-olds and consistently high levels appropriate response regardless of the variation of demanded relation. These findings suggest that older children are more flexible in using their conceptual knowledge. However, younger children have a stronger tendency to depend on thematic relation for grouping objects.