Duties are universally measured by relations ([Greek: tais schsesi]).
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 neighbor, from that of a citizen, from that of a general, if you
are accustomed to contemplate the relations.