Sadness usually results from one of the following causes either when a man does not succeed, or is ashamed of his success.
Seneca the YoungerWe are born to lose and to perish, to hope and to fear, to vex ourselves and others; and there is no antidote against a common calamity but virtue; for the foundation of true joy is in the conscience.
Seneca the YoungerSome pretend want of power to make a competent return; and you shall find in others a kind of graceless modesty, that makes a man ashamed of requiting an obligation, because it is a confession that he has received one.
Seneca the Younger