There is, as Dr. John Dewey points out,[6] a contradiction between Herbart’s Pedagogy and his Psychology, as follows: the Pedagogy regards interest as the lever of education, the means for securing spontaneous activity of mind; the Psychology regards interest as a feeling arising from the relation of ideas. Ideas must therefore be _given_, in right relations, to arouse interest, while interest is in turn conceived as the means of arousing them. This is reasoning in a circle. The difficulty arises from asserting the primacy of ideas in mental life, and then speaking of _self-activity_, which presupposes the primacy of motor, or impulsive activities. The reader will avoid all contradictions in educational theory by accepting the modern view of the primacy, not of ideas, but of what may broadly be termed _will_. The latter view is in accord with biological and historical science. Ideas are a later production of mind; they serve to define more clearly the ends for which we work, at the same time giving us insight into the best means of attaining them. For an interesting discussion of the primacy of the will, the reader is referred to Professor Paulsen’s “Introduction to Philosophy,” pp. 111–122.[7] [6] “Interest as Related to Will,” pp. 237–241, Second Supplement to First Herbart Year Book. [7] Henry Holt & Co., New York, 1895. 74. Involuntary [spontaneous] attention is subdivided into primitive and apperceiving. The latter especially is of the greatest importance in teaching, but it rests on the former, the conditions of which must constantly be taken into account. Apperception, or assimilation, takes place through the reproduction of previously acquired ideas and their union with the new element, the most energetic apperception, although not necessarily the best, being effected by the ideas rising spontaneously. This topic will be treated more fully below (77). Here it suffices to say that the apperceiving attention obviously presupposes the primitive attention; otherwise apperceiving ideas would never have been formed. The psychological and educational importance of the idea of apperception, or the assimilation of knowledge, has been much emphasized in recent years. For a psychological interpretation of the theory, the reader is referred to Wundt’s “Human and Animal Psychology,”[8] pp. 235–251. The educational significance of the doctrine has been well brought out by Dr. Karl Lange, in his able monograph on “Apperception.”[9] The subject has been more popularly treated in Dr. McMurray’s “General Method,”[10] and in the writer’s “Essentials of Method”[11]; also in a number of other works. [8] New York, Macmillan & Co., 1894. [9] Boston, D. C. Heath & Co., 1894. [10] Bloomington, Ill., Public School Pub. Co., 1894. [11] Boston, D. C. Heath & Co., 1893.