Separating the sheep from the goats: Differentiating global categories

The nature of the conceptual categories that children have developed in the second year was studied in a series of experiments using an object-manipulation task. In the first two experiments, it was shown that by 18 months children have developed global conceptual categories of animals and vehicles without yet clearly differentiating basic-level categories within these domains. The basic-level categories were tested by using a series of...