And, as for physical attitudes, etc., hear what several eminent psychologists tell us. Prof. Halleck says: "By inducing an expression we can often cause its allied emotion." Prof. James says: "Whistling to keep up courage is no mere figure of speech. On the other hand, sit all day in a moping posture, sigh, and reply to everything with a dismal voice, and your melancholy lingers. There is no more valuable precept in moral education than this: If we wish to conquer undesirable emotional tendencies in ourselves we must assiduously, and in the first instance cold-bloodedly, go through the _outward movements_, of those contrary dispositions which we wish to cultivate. Smooth the brow, brighten the eye, contract the dorsal rather than the ventral aspect of the frame, and speak in a major key, pass the genial compliment and your heart must indeed be frigid if it does not gradually thaw." Dr. Woods Hutchinson says: "To what extent muscular contractions condition emotions, as Prof. James has suggested, may be easily tested by a quaint and simple little experiment upon a group of the smallest voluntary muscles of the body, those that move the eyeball. Choose some time when you are sitting quietly in your room, free from all disturbing thoughts and influences. Then stand up, and assuming an easy position, cast the eyes upward, and hold them in that position for thirty seconds. Instantly and involuntarily you will be conscious of a tendency toward reverential, devotional, contemplative ideas and thoughts. Then turn the eyes sideways, glancing directly to the right or to the left, through half-closed lids. Within thirty seconds images of suspicion, of uneasiness, or of dislike will rise unbidden to the mind. Turn the eyes on one side and slightly downward, and suggestions of jealousy or coquetry will be apt to spring unbidden. Direct your gaze downward toward the floor, and you are likely to go off into a fit of reverie or abstraction." Maudsley says: "The specific muscular action is not merely an exponent of passion, but truly an essential part of it. If we try while the features are fixed in the expression of one passion to call up in the mind a different one, we shall find it impossible to do so." In view of the above statements, we may readily see the importance of cultivating those outward expressions which are co-related to desirable mental states or feelings. By so doing we arouse in our minds those particular states or feelings. And, moreover, we tend to impress others with the possession on our part of the co-related mental qualities. One's outward expression is a powerful instrument of suggestion to others, and people are unconsciously and instinctively affected by it, to our benefit or detriment. Let us therefore consider, briefly, the general principles underlying personal expression along the lines indicated.