Enchiridion XXX

XXX

Duties are universally measured by relations. Is a certain man your father? In this are implied taking care of him, submitting to him in all things, patiently receiving his reproaches, his correction. But he is a bad father. Is your natural tie, then, to a good father? No, but to a father. Is a brother unjust? Well, preserve your own just relation toward him. Consider not what he does, but what you are to do to keep your own will in a state conformable to nature, for another cannot hurt you unless you please. You will then be hurt when you consent to be hurt. In this manner, therefore, if you accustom yourself to contemplate the relations of neighbor, citizen, commander, you can deduce from each the corresponding duties.

That very first premise is widely challenged by contemporary philosophy, which wants to consider duties as universal in character. Rawls, famously, argued that we should imagine (because we cannot actually do it) devising the moral rules in a 'veil of ignorance,' behind which we should know nothing about our actual circumstances. Some who consider themselves Kantian thinkers argue that Kant's dictum that you can only act properly under a maxim that could be expressed as a universal moral law requires treating all people exactly equally -- but Kant, of course, would never have accepted that you ought not to pay special attention to your father. Kant's actual moral vision was highly conservative, once he got around to spelling it out in the Metaphysics of Morals. It's only people who stop with the Groundwork to the Metaphysics of Morals -- which is far more popular, being both shorter and more theoretical -- who can imagine he would have endorsed any such thing.

Epictetus says something that would have been morally obvious to everyone in his age, and in every earlier age, and almost every subsequent age. That it has become controversial points to the weakness of our own.

This view of duty expands outwards in accordance with the relations we bear to each other. I owe duties to my family that I do not to others; to my neighbors that I do not to others; to my fellow citizens that I do not to others. (This too is now highly controversial among the Managers, who would have us bear duties to the entire world while washing citizenship of any meaning: disloyalty to the demos from those who describe themselves as democrats.) Doing your duty in each of your relations satisfies your duties to the semblances you encounter of the things outside. 

In fact, though, you have only done your duty to yourself. You have behaved as one ought to do, given what you think you know your relations and duties to be. In that way you have lived with honor, and thus can rest in honor. The injustice the semblances may produce is their own concern: you know you have done right, and are satisfied.