An abstract to concrete shift in the development of biological thought: the insides story.

For more than a century, theorists of cognitive development have embraced some form of the thesis that cognitive development proceeds from concrete to abstract knowledge. In contrast to this view, we suggest an abstract to concrete shift in the development of biological thought. In five studies we examine children's expectations for what could be inside animals and machines and we find that children of all ages respond systematically, revealing abstract expectations for how the insides of animals and machines should differ. By 8 years, children seem to have more concrete expectations for the nature of insides, and are substantially more accurate than preschoolers. More broadly, we suspect that an abstract to concrete progression may capture important features of how knowledge develops in the realm of biological thought and in many other areas of understanding as well.