The science of Pedagogics cannot be derived from a simple principle with such exactness as Logic and Ethics. It is rather a mixed science which has its presuppositions in many others. In this respect it resembles Medicine, with which it has this also in common, that it must make a distinction between a sound and an unhealthy system of education, and must devise means to prevent or to cure the latter. It may therefore have, like Medicine, the three departments of Physiology, Pathology, and Therapeutics.
