Duty
"One of the most destructive anti-concepts in the history of moral philosophy is the term "duty."
An anti-concept is an artificial, unnecessary and rationally unusable term designed to replace and obliterate some legitimate concept. The term "duty" obliterates more than single concepts; it is a metaphysical and psychological killer: it negates all the essentials of a rational view of life and makes them inapplicable to man's actions . . . .
The meaning of the term "duty" is: the moral necessity to perform certain actions for no reason other than obedience to some higher authority, without regard to any personal goal, motive, desire or interest.
It is obvious that that anti-concept is a product of mysticism, not an abstraction derived from eality. In a mystic theory of ethics, "duty" stands for the notion that man must obey the dictates of a supernatural authority. Even though the anti-concept has been secularized, and the authority of God's will has been ascribed to earthly entities, such as parents, country, State, mankind, etc., their alleged supremacy still rests on nothing but a mystic edict. Who in hell can have the right to claim that sort of submission or obedience? This is the only proper form - locality - for the question, because nothing and no one can have such a right or claim here on earth.
The arch-advocate of "duty" is Immanuel Kant; he went so much further than other theorists that they seem innocently benevolent by comparison. "Duty," he holds, is the only standard of virtue; but virtue is not its own reward: if a reward is involved, it is no longer virtue. The only moral motivation, he holds, is devotion to duty for duty's sake; only an action motivated exclusively by such devotion is a moral action . . . .
If one were to accept it, the anti-concept "duty" destroys the concept of reality: an unaccountable, supernatural power takes precedence over facts and dictates one's actions regardless of context or consequences.
"Duty" destroys reason: it supersedes one's knowledge and judgment, making the process of thinking and judging irrelevant to one's actions.
"Duty" destroys values: it demands that one betray or sacrifice one's highest values for the sake of an inexplicable command - and it transforms values into a threat to one's moral worth, since the experience of pleasure or desire casts doubt on the moral purity of one's motives.
"Duty" destroys love: who could want to be loved not from "inclination," but from "duty"?
"Duty" destroys self-esteem: it leaves no self to be esteemed.
If one accepts that nightmare in the name of morality, the infernal irony is that "duty" destroys morality.
~ Found at Ayn Rand Lexicon - Duty