Bounds.

In the morning when thou risest unwillingly, let this thought be present,—I am rising to the work of a human being. Why then am I dissatisfied if I am going to do the things for which I exist and for which I was brought into the world? Or have I been made for this, to lie in the bed-clothes and keep myself warm?—But this is more pleasant.—Dost thou exist then to take thy pleasure, and not at all for action or exertion? Dost thou not see the little plants, the little birds, the ants, the spiders, the bees working together to put in order their several parts of the universe? And art thou unwilling to do the work of a human being, and dost thou not make haste to do that which, is according to thy nature? But it is necessary to take rest also.—It is necessary. However, Nature has fixed bounds to this too: she has fixed bounds to eating and drinking, and yet thou goest beyond these bounds, beyond what is sufficient; yet in thy acts it is not so, but thou stoppest short of what thou canst do. So thou lovest not thyself, for if thou didst, thou wouldst love thy nature and her will. But those who love their several arts exhaust themselves in working at them unwashed and without food; but thou valuest thy own nature less than the turner values the turning art, or the dancer the dancing art, or the lover of money values his money, or the vain-glorious man his little glory. And such men, when they have a violent affection to a thing, choose neither to eat nor to sleep rather than to perfect the things which they care for. But are the acts which concern society more vile in thy eyes and less worthy of thy labor?

Marcus Aurelius, from the Fifth Book of Meditations