A causal interpretation of John Dewey on teaching also finds support in Dewey's suggestion that the most compelling reason to believe in the principle of causation is the human capacity for labour. Curriculum theorist James A. Beane makes a distinction crucial to interpreting the variables Internal Curriculum Coherence and External Curriculum Coherence in Dewey's law. Interestingly, Dewey's law provides a parallel general heuristic with which teachers can begin a process of inquiry into how best to carry out the instructional tasks set them. Discovery of Dewey's law meets the universal formula condition of causal adequacy imposed by Dewey's theory of causation. Development of adaptations of curriculum in terms of the variables of Dewey's law is an experimental process. Even more importantly, however, Dewey's law goes about describing good teaching in terms of the creation of educational energy. Dewey's law offers a paradigm of teaching in both the broad and the narrow sense of the word as used by Thomas Kuhn.