Keil aimed at investigating whether the discovery of internal essences, or underlying causal principies, would affeet the way children categorize concepts of natural species and artifacts. The present paper replicates part of Keil' s (1989) experiment. The purpose was to ascertain whether the results were applicable to the Brazilian culture. Thirty children were assigned to three groups of 617, 8/9, and 10/11 years of age. Each was told four stories elaborated by Keil, previously translated, two of them were about natural species and the other two were about artifacts. They depicted situations in which scientists "discovered" that the properties that defined something were hidden under the surface aspects of something else. At the end of each one, the experimenter asked the child whether it was a case of X (i.e., the appearance of an objeet), or Y (i.e., the defining attributes of the object). With respect to artifacts, subjects were not misled by surface aspects, but rather were able to correctly assess the identity of the artifacts. However, with regard to natural species, the defining attributes were effective only for the older children. These findings give support to Keil's ones.
Concept formation; Conceptual development; Theory view
