DUTY, n.
That which sternly impels us in the direction of profit, along the line of desire.
Sir Lavender Portwine, in favor at court, Was wroth at his master, who'd kissed Lady Port. His anger provoked him to take the king's head, But duty prevailed, and he took the king's bread, Instead.
G.J.
--Ambrose Bierce - The Devil's Dictionary