A man's indebtedness is not virtue; his repayment is. Virtue begins when he dedicates himself actively to the job of gratitude.
— Ruth Benedict

Great indebtedness does not make men grateful, but vengeful; and if a little charity is not forgotten, it turns into a gnawing worm.
— Friedrich Nietzsche

Anybody who has ever been in business, anybody who has ever paid bills, anybody who has ever lived in a serious adult life knows that indebtedness is a killer.
— Frank Lautenberg