There is a note that comes into the human voice by which you may know real weariness. It comes when one has been trying with all his heart and soul to think his way along some difficult road of thought. Of a sudden he finds himself unable to go on. Something within him stops. A tiny explosion takes place. He bursts into words and talks, perhaps foolishly. Little side currents of his nature he didn't know were there run out and get themselves expressed. It is at such times that a man boasts, uses big words, makes a fool of himself in general.