Lakes resting one on the other. Join with friends for discussion and practice. A lake evaporates upward and gradually dries up; but when two lakes are joined they do not dry up so readily, for one replenishes the other. In the field of knowledge, it becomes a refreshing and vitalizing force only through stimulating intercourse with congenial friends. In this way learning becomes many-sided and takes on cheerful lightness, whereas there is always something ponderous and one-sided about the learning of the self-taught.