This is the true joy of life-the being used for a purpose recognized by yourself as a mighty one, the being thoroughly worn out before you are thrown to the scrap-heap; the being a force of nature instead of a feverish, selfish clod of ailments and grievances.
Friends hold a mirror up to each other; through that mirror they can see each other in ways that would not otherwise be accessible to them, and it is this mirroring that helps them improve themselves as persons.