Studies in Pessimism, by Arthur Schopenhauer

"If two men who were friends in their youth meet again when they are old, after being separated for a life-time, the chief feeling they will have at the sight of each other will be one of complete disappointment at life as a whole; because their thoughts will be carried back to that earlier time when life seemed so fair as it lay spread out before them in the rosy light of dawn, promised so much — and then performed so little. This feeling will so completely predominate over every other that they will not even consider it necessary to give it words; but on either side it will be silently assumed, and form the ground-work of all they have to talk about."