A teacher may destroy his power to awaken and stimulate thought by developing every subject in all its bearings to its logical or final conclusion. He should send his classes away from the daily lecture or recitation to the library or the laboratory, to the study, the shop, or the field, with the sense of something to be achieved, with the feeling that there are fields of research for them to explore, fields that will amply repay careful study, investigation, and reflection. There is nothing that tires a boy so soon as the feeling that there is nothing for him to do, nothing that he can master, achieve, or conquer on his own account. The normal child is so constituted that it loves activity, looks into the future, and regards itself as an important factor in the world’s life. The advance from childhood to youth is marked by a transition into the period that is brimful of hope and ambition. The pampered son of a rich man may feel no longing of this sort; his opportunities for early travel and premature indulgence in every whim may have brought him to the point where the whole world seems like a sucked orange for which one has no further use. Unless the rich father and mother possess an extraordinary amount of good sense, their children do not have an even chance with the children of the middle classes whose outlook upon life supplies abundant motives for study and exertion.
If a boy has not made a mistake in selecting his parents, if the atmosphere of the home in which his first six years are spent is normal, he comes to school with a sense of something to be achieved. Should this feeling be lacking, the true teacher will aim to beget it by the instruction he gives and by appeals to the innate desire for knowledge. As the intelligence dawns, the interrogation points on the boy’s face multiply; his appetite for knowledge grows by what it feeds on. If the branches of study do not become more interesting than any occupation by which the boy can earn coppers, there is something wrong either with the boy or his teacher, or with both. In the ascent of the hill of science every step upward widens the horizon, increases the field of vision, and stimulates to new effort. Every field explored beckons to new fields of investigation. It is the prerogative of the teacher to point out what is in store for the aspiring youth. Take, for instance, the domain of pure mathematics. A pupil had learned in his geometry that parallel lines never meet. The teacher told him that his geometrical studies would after a while acquaint him with lines that are not parallel and yet never meet. No sooner had he met lines of this kind, situated in different planes, than his teacher told him of lines that continually approach but never meet. The appeal to his curiosity helped to stimulate the desire for knowledge and kept him thinking earnestly and seriously until he met the asymptote and its curve. The study of asymptotes soon grew more interesting than chess or any sports upon the athletic field.