. . . nothing is miserable except when you think it so, and vice versa, all luck is good luck to the man who bears it with equanimity. No one is so happy that he would not want to change his lot if he gives in to impatience. Such is the bittersweetness of human happiness. To him that enjoys it, it may seem full of delight, but he cannot prevent it slipping away when it will. It is evident, therefore, how miserable the happiness of human life is . . . .

— Anicius Manlius Severinus Boethius