Or take the emotion of anger. Some fine morning in school everything is in good order, everybody is industriously at work, the lessons are proceeding satisfactorily. The current of the teacher's experience is flowing smoothly and unobstructedly. Presently a troublesome boy, who has been repeatedly reproved for misconduct, again shows symptoms of idleness and misbehaviour. The smooth current of experience being checked, here also both a new feeling tone is experienced and the wonted nerve currents flow out into other brain centres. The teacher stops his work and gazes fixedly at the offending pupil. His heart beats rapidly, the blood surges to his face, his breathing becomes heavy, his muscles grow tense. In these reactions we have the nervous currents passing out over involuntary channels. Then, perhaps, the teacher unfortunately breaks forth into a torrent of words or lays violent hands upon the offender. Here the nervous currents are passing outward over the voluntary system. These illustrations indicate that three important conditions are present at the appearance of the emotion, namely, (1) the presence of an unusual object in consciousness, (2) the consequent disturbance of the smooth flow of experience or, in physiological terms, the temporary obstruction of the ordinary pathways of nervous discharge through the great resistance encountered, and (3) the new feeling state with its concomitant overflow of the impulses into new motor channels, some of which lead to the involuntary muscles and others to the voluntary. The emotion proper consists in the feeling state which arises as a result of the resistance encountered by the nervous impulses as the smooth flow of experience is checked. The idea that I shall die some day arouses no emotion in me, because it in no way affects my ordinary thought processes, and therefore it in no way disturbs my nervous equilibrium. The perception of a wild animal about to kill me, because it suddenly thwarts and impedes the smooth flow of my experience through a suggestion of danger, produces an intense feeling and a diffused and intense derangement of the nervous equilibrium. =Development of Emotions.=--The question of paramount importance in connection with emotion is how to arouse and develop desirable emotions. The close connection of the three phases of the mind's manifestation--knowing, feeling, and willing, gives the key to the question. Feeling cannot be developed alone apart from knowing and willing. In fact, if we attend carefully to the knowing and willing activities, the feelings, in one sense, take care of themselves. Two principles, therefore, lie at the basis of proper emotional development: