ABSTRACT
Some learn better when they are happy, others perhaps when the conditions are austere or comfortable enough not to be distracting. Understanding, moreover, involves and presupposes the acquisition and use of concepts. One can understand nothing of a subject unless one has the concepts in which that understanding is to be expressed. Explanatory theories, e.g. scientific theories, have a logical structure in the sense that the propositions of which the theory is constituted can be arranged in a certain order, so that certain propositions can be derived from others. It seems to the author that Piaget’s discoveries here are like discovering that circles when presented to people in a frontal plane look round to them. Psychology has much to tell the reader about learning – about, for example, particular cases and individual differences.
