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:
1. The mind must be allowed to dwell upon only those ideas to which worthy emotions are attached. We must refuse to think those thoughts that are tinged with unworthy feelings. The Apostle Paul has expressed this very eloquently when he says in his Epistle to the Philippians: "Finally, brethren, whatsoever things are true, whatsoever things are honest, whatsoever things are just, whatsoever things are pure, whatsoever things are lovely, whatsoever things are of good report; if there be any virtue, and if there be any praise, think on these things."