Meditations by Marcus Aurelius Book 6 Page 23

unnatural. So a man as long as he doth that which is proper unto a man, his labour cannot be against nature; and if it be not against nature, then neither is it hurtful unto him. But if it were so that happiness did consist in pleasure: how came notorious robbers, impure abominable livers, parricides, and tyrants, in so large a measure to have their part of pleasures?

XXXII. Dost thou not see, how even those that profess mechanic arts, though in some respect they be no better than mere idiots, yet they stick close to the course of their trade, neither can they find in their heart to decline from it: and is it not a grievous thing that an architect, or a physician shall respect the course and mysteries of their profession, more than a man the proper course and condition of his own nature, reason, which is common to him and to the Gods?