Enchiridion 30

Our duties are in general measured by our social relationships. He is a father. One is called upon to take care of him, to give way to him in all things, to submit when he reviles or strikes you. "But he is a bad father." Did nature, then, bring you into relationship with a good father? No, but simply with a father. "My brother does me wrong." Very well, then, maintain the relation that you have toward him; and do not consider what he is doing, but what you will have to do, if your moral purpose is to be in harmony with nature. For no one will harm you without your consent; you will have been harmed only when you think you are harmed. In this way, therefore, you will discover what duty to expect of your neighbour, your citizen, your commanding officer, if you acquire the habit of looking at your social relations with them.

Epictetus, Enchiridion 30, translated by W. A. Oldfather

Duties are universally measured by relations (ταῖς σχέσεσι). Is a man a father? The precept is to take care of him, to yield to him in all things, to submit when he is reproachful, when he inflicts blows. But suppose that he is a bad father. Were you then by nature made akin to a good father? No; but to a father. Does a brother wrong you? Maintain then your own position towards him, and do not examine what he is doing, but what you must do that your will shall be conformable to nature. For another will not damage you, unless you choose: but you will be damaged then when you shall think that you are damaged. In this way then you will discover your duty from the relation of a neighbour, from that of a citizen, from that of a general, if you are accustomed to contemplate the relations.

Epictetus, Enchiridion 30, translated by George Long

Appropriate acts are in general measured by the relations they are concerned with. 'He is your father.' This means you are called on to take care of him, give way to him in all things, bear with him if he reviles or strikes you.

'But he is a bad father.'

Well, have you any natural claim to a good father? No, only to a father.

'My brother wrongs me.'

Be careful then to maintain the relation you hold to him, and do not consider what he does, but what you must do if your purpose is to keep in accord with nature. For no one shall harm you, without your consent; you will only be harmed, when you think you are harmed. You will only discover what is proper to expect from neighbour, citizen, or praetor, if you get into the habit of looking at the relations implied by each.

Epictetus, Enchiridion 30, translated by P. E. Matheson