Marcus Aurelius: “Constantly observe who those are whose approbation thou wishest to have, and what ruling principles they possess.”

Be cheerful also, and seek not external help nor the tranquillity which others give.

Labor not unwillingly, nor without regard to the common interest, nor without due consideration, nor with distraction; nor let studied ornament set off thy thoughts, and be not either a man of many words, or busy about too many things.

Further, he was not fond of change nor unsteady, but he loved to stay in the same places, and to employ himself about the same things; and after his paroxysms of headache he came immediately fresh and vigorous to his usual occupations.

Whatever this is that I am, it is a little flesh and breath, and the ruling part.