Get knowledge of the spine, for this is the requisite for many diseases

That which is used - develops. That which is not used wastes away.

Fat people who want to reduce should take their exercise on an empty stomach and sit down to their food out of breath.... Thin people who want to get fat should do exactly the opposite and never take exercise on an empty stomach.

Foolish the doctor who despises the knowledge acquired by the ancients.

About medications that are drunk or applied to wounds it is worth learning from everyone; for people do not discover these by reasoning but by chance, and experts not more than laymen.

Men ought to know that from the brain and from the brain only arise our pleasures, joys, laughter, and jests as well as our sorrows, pains, griefs and tears. ... It is the same thing which makes us mad or delirious, inspires us with dread and fear, whether by night or by day, brings us sleeplessness, inopportune mistakes, aimless anxieties, absent-mindedness and acts that are contrary to habit.

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.