Marcus Aurelius
Meditations 10.6
Whether the universe is [a concourse of] atoms, or nature [is a system], let this first be established, that I am a part of the whole which is governed by nature; next, I am in a manner intimately related to the parts which are of the same kind with myself. For remembering this, inasmuch as I am a part, I shall be discontented with none of the things which are assigned to me out of the whole; for nothing is injurious to the part if it is for the advantage of the whole. For the whole contains nothing which is not for its advantage; and all natures indeed have this common principle, but the nature of the universe has this principle besides, that it cannot be compelled even by any external cause to generate anything harmful to itself. By remembering, then, that I am a part of such a whole, I shall be content with everything that happens. And inasmuch as I am in a manner intimately related to the parts which are of the same kind with myself, I shall do nothing unsocial, but I shall rather direct myself to the things which are of the same kind with myself, and I shall turn all my efforts to the common interest, and divert them from the contrary. Now, if these things are done so, life must flow on happily, just as thou mayst observe that the life of a citizen is happy, who continues a course of action which is advantageous to his fellow-citizens, and is content with whatever the state may assign to him.
Marcus Aurelius, Meditations 10.6, translated by George Long
Whether there be atoms or a Nature, let it be postulated first, that I am a part of the whole Universe controlled by Nature; secondly, that I stand in some intimate connexion with other kindred parts. For bearing this in mind, as I am a part, I shall not be displeased with anything allotted me from the Whole. For what is advantageous to the whole can in no wise be injurious to the part. For the Whole contains nothing that is not advantageous to itself; and all natures have this in common, but the Universal Nature is endowed with the additional attribute of never being forced by any external cause to engender anything hurtful to itself.
As long then as I remember that I am a part of such a whole, I shall be well pleased with all that happens; and in so far as I am in intimate connexion with the parts that are akin to myself, I shall be guilty of no unsocial act, but I shall devote my attention rather to the parts that are akin to myself, and direct every impulse of mine to the common interest and withhold it from the reverse of this. That being done, life must needs flow smoothly, as thou mayst see the life flow smoothly of a citizen who goes steadily on in a course of action beneficial to his fellow-citizens and cheerfully accepts whatever is assigned him by the State.
Marcus Aurelius, Meditations 10.6, translated by C. R. Haines