Early differentiation of causal mechanisms appropriate to biological and nonbiological kinds.

Although Piaget characterized young children as precausal until about 7-8 years of age, recent work indicates that preschoolers do honor fundamental principles of causality. This literature has mainly focused on general principles invoked in reasoning about mechanical events. By contrast, the present study examined whether children differentiate between the causal mechanisms appropriate for different conceptual domains. The results of 3 preliminary investigations and 1 main experiment suggested that preschoolers prefer natural mechanisms for color inheritance in biological kinds, particularly when causal substrates resemble their consequences. By contrast, the same children recognized the importance of human intentions in producing the color of an artifact, and also judged that mechanical mechanisms serve to mediate between intentions and outcomes. The results are relevant to recent studies on the development of biological thought, and overall suggest that early causal reasoning reflects both domain-specific and domain-general principles.