There are some arts which to those that possess them are painful, but to those that use them are helpful, a common good to laymen, but to those that practise them grievous. Of such arts there is one which the Greeks call medicine. For the medical man sees terrible sights, touches unpleasant things, and the misfortunes of others bring a harvest of sorrows that are peculiarly his; but the sick by means of the art rid themselves of the worst of evils, disease, suffering, pain and death.

Science begets knowledge; opinion, ignorance.

And if this were so in all cases, the principle would be established, that sometimes conditions can be treated by things opposite to those from which they arose, and sometimes by things like to those from which they arose.

Things that are holy are revealed only to men who are holy.

Life is short and the art long.

What medicines do not heal, the lance will; what the lance does not heal, fire will.

A physician without a knowledge of Astrology has no right to call himself a physician.