=Firing Up the Engine.= Purpose is writ large across the face of an instinct, and that purpose is always toward action. Whenever a situation arises which demands instantaneous action, the instinct is the means of securing it. Planted within the creature is a tendency which makes it perceive and feel and act in the appropriate way. It will be noticed that there are three distinct parts to the process, corresponding to intellect, emotion, will. The initial intellectual part makes us sensitive to certain situations, makes us recognize an object as meaningful and significant, and waves the flag for the emotion; the emotion fires up the engine, pulls the levers all over the body that release its energy and get it ready for action, and pushes the button that calls into the mind an intense, almost irresistible desire or impulse to act. Once aroused, the emotion and the impulse are not to be changed. In man or beast, in savage or savant, the intense feeling, the marked bodily changes, and the yearning for action are identical and unchangeable. The brakes can be put on and the action suppressed, but in that case the end of the whole process is defeated. Could anything be plainer than that an instinct and its emotion were never intended to be aroused except in situations in which their characteristic action is to be desired? An emotion is the hot part of an instinct and exists solely for securing action. If all signs of the emotion are to be suppressed, all expression denied, why the emotion? But although the emotion and the impulse, once aroused, are beyond control, there is yet one part of the instinct that is meant to be controlled. The initial or receptive portion, that which notices a situation, recognizes it as significant, and sends in the signal for action, can be trained to discrimination. This is where reason comes in. If the situation calls for flight, fear is in order; if it calls for fight, anger is in order; if it calls for examination, wonder is in order; but if it calls for none of these things, reason should show some discrimination and refuse to call up the emotion.