Meditations 6.35

Dost thou not see how the handicrafts-men accommodate themselves up to a certain point to those who are not skilled in their craft—nevertheless they cling to the reason [the principles] of their art, and do not endure to depart from it? Is it not strange if the architect and the physician shall have more respect to the reason [the principles] of their own arts than man to his own reason, which is common to him and the gods?

Marcus Aurelius, Meditations 6.35, translated by George Long

Dost thou not see how the mechanic craftsman, though to some extent willing to humour the non-expert, yet holds fast none the less to the principles of his handicraft, and cannot endure to depart from them. Is it not strange that the architect and the physician should hold the rationale of their respective arts in higher reverence than a man his own reason, which he has in common with the Gods?

Marcus Aurelius, Meditations 6.35, translated by C. R. Haines