Here we find the principle that governs the choice of material for successful memorizing. And as to the amount--so much as is needed for the immediate future; for excessive quantity promotes an early forgetting. Besides, in instruction, as in experience, there is a great deal that may not be accurately remembered, but nevertheless renders abundant service by stimulating the mind and qualifying it for further work. CHAPTER V =The Main Kinds of Interest= 83. Instruction is to be linked to the knowledge that experience provides, and to the ethical sentiments that arise from social intercourse (36). Empirical interest relates directly to experience; sympathetic interest to human association. Discursive reflection on the objects of experience involves the development of speculative interest, reflection on the wider relations of society that of social interest. With these we group, on the one hand æsthetic, on the other religious interest, both of which have their origin not so much in discursive thought as in a non-progressing contemplation of things and of human destiny. The classification of interests into two groups, namely, (a) those which arise from knowledge, and (b) those which arise from association with others, and the subdivision of each of these into three groups, making six in all, is one not of necessity, but of convenience. The knowledge interests are, (a) empirical, (b) speculative, (c) æsthetic; the interests arising from association are, (a) sympathetic, (b) social, (c) religious. This classification is adopted without criticism by most Herbartian writers. That the classification is made simply for convenience may be seen from such considerations as the following:-- 1. Strictly speaking, _all_ interests arise from _experience_, the social no less than the speculative; hence experience is not a basis for classification at all. 2. Æsthetic interests, resting upon contemplation, need not be put into a group with those that rest upon the perception of cause and effect, or other relations perceived by discursive reflection. 3. The same is true for those empirical interests that are supposed to rest upon immediate sense apprehension, such as the interest in color, shape, sound, taste, odor. 4. If perception, reasoning, and sensibility are made bases for the classification of interests, why should not the active volitional powers of the mind become a basis likewise? Some claim that pleasure and pain rest primarily upon the _motor_ side of our activity, rather than upon the sensory. Our interest in _doing_ is antecedent to our interest in knowing or feeling. This fact is fully recognized by all Herbartians in the theory of methods, though it finds no recognition in their classification of interests. It must be granted, however, that Herbart’s classification is convenient, even if not especially scientific.