Meditations 9.23

As thou thyself art a component part of a social system, so let every act of thine be a component part of social life. Whatever act of thine then has no reference either immediately or remotely to a social end, this tears asunder thy life, and does not allow it to be one, and it is of the nature of a mutiny, just as when in a popular assembly a man acting by himself stands apart from the general agreement.

Marcus Aurelius, Meditations 9.23, translated by George Long

As thou thyself art a part perfective of a civic organism, let also thine every act be a part perfective of civic life. Every act of thine then that has no relation direct or indirect to this social end, tears thy life asunder and destroys its unity, and creates a schism, just as in a commonwealth does the man who, as far as in him lies, stands aloof from such a concord of his fellows.

Marcus Aurelius, Meditations 9.23, translated by C. R. Haines