A great man is one who has conquered himself. He has brought order, discipline and meaning into his life and prevented it from becoming the aimless, self-centered, repulsive existence to which he is drawn by his inherited weaknesses. The process begins when a man brings a center of interest into his life. This interest must be something inspiring and elevating. If you push these requirements far enough, the center of his life can only be God.
The fact is that we can find happiness only in serving others. Just as a car is designed to move, so is a man designed to serve. And if he looks for happiness in anything other than service and sacrifice, he will always be disappointed.