monest processes of knowledge acquire a new significance.
Two kinds of activity are concerned in the attainment of knowledge. One kind consists in simply receiving impressions from without, such as sensations, or, on a higher plane, statements of truth; the other consists in modifying and in organizing these impressions. The receptive activity is partly a physical activity, since the one who receives information must use his eyes and ears, must keep awake, must at times move about; and this receptive activity is also partly made up of the mechanical processes of the memory. Association by contiguity, or learning by rote, is in the main a receptive process, though this process of reception requires some active effort on the part of the receiver. Committing words and sentences to memory is often hard labor, as we all of us learned when we first were tortured with ill-wrought geographies and grammars, or with merciless Latin declensions and conjugations. But of the whole of this receptive activity we shall make no further mention in this connection. Simply receiving, keeping your mind in a submissive attitude, turning your eyes in the proper direction, using your ears, writing down your notes, memorizing whatever needs memorizing — all this is essential to knowledge, but has no reactive effect, does not modify the form or the matter of your knowledge. Secondly, however, knowledge is determined for each of us by his own reaction upon what he receives; and this second mentioned kind of mental activity, that which forms our topic at present, consists in a modi-
