The papers in this volume provide a coherent philosophical study of a group of important and pressing educational issues such as the selection of objectives for less able children, the fundamental characteristics of teaching and the integration of the curriculum. A thesis on the necessary differentiation of knowledge into logically distinct forms is outlined, and is defended against recent philosophical criticisms. Its implications for curriculum planning are examined, with particular reference to the urgent problems of adeqately characterizing liberal education and those forms of moral and religious education that are appropriate in maintained schools.