Old people have fewer diseases than the young, but their diseases never leave them.

All parts of the body which have a function, if used in moderation and exercised in labors in which each is accustomed, become thereby healthy, well developed and age more slowly, but if unused they become liable to disease, defective in growth and age quickly.

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.

All excesses are inimical to Nature. It is safer to proceed a little at a time, especially when changing from one regimen to another.

Through seven figures come sensations for a man; there is hearing for sounds, sight for the visible, nostril for smell, tongue for pleasant or unpleasant tastes, mouth for speech, body for touch, passages outwards and inwards for hot or cold breath. Through these come knowledge or lack of it.

The human body contains blood, phlegm, yellow bile and black bile. These are the things that make up its constitution and cause its pain and health. Health is primarily that state in which these constituent substances are in the correct proportion to each other, both in strength and quantity, and are well mixed.

From nothing else but the brain come joys, delights, laughter and sports, and sorrows, griefs, despondency, and lamentations