Root of veins, liver; root of arteries, heart. Out of these travel to all parts blood and breath, and heat passes through them.

Power one, and not one, by which all these things and those of a different sort are managed; one for the life of whole and part, not one for the sensation of whole and part.

Milk nutriment, for those to whom milk is a natural nutriment, but for others it is not. For some wine is nutriment, for others not. So with meats and the other many forms of nutriment, the differences being due to place and habit.

Nourishment is sometimes into growth and being, sometimes into being only, as is the case with old men; sometimes in addition it is into strength. The condition of the athlete is not natural. A healthy state is superior in all.

It is a great thing successfully to adapt quantity to power.