To what extent do children understand that biological processes fall into 1 coherent domain unified by distinct causal principles? In Experiments 1 and 2 (N = 125) kindergartners are given triads of biological and psychological processes and asked to identify which 2 members of the triad belong together. Results show that 5-year-olds correctly…

In 4 studies, the authors examined how intuitions about the relative difficulties of the sciences develop. In Study 1, familiar everyday phenomena in physics, chemistry, biology, psychology, and economics were pretested in adults, so as to be equally difficult to explain. When participants in kindergarten, Grades 2, 4, 6, and 8, and college were…