Psychiatrists declare that most of our fatigue derives from our mental and emotional attitudes... What kinds of emotional factors tire the sedentary (or sitting) worker? Joy? Contentment? No! Never! Boredom, resentment, a feeling of not being appreciated, a feeling of futility, hurry, anxiety, worry-those are the emotional factors that exhaust the sitting worker, make him susceptible to colds, reduce his output, and send him home with a nervous headache. Yes, we get tired because our emotions produce nervous tensions in the body.
Dale CarnegieIf you argue and rankle and contradict, you may achieve a victory sometimes; but it will be an empty victory because you will never get your opponent's good will.
Dale Carnegie