Book 2
9
Now, it seems to me that Erasistratus is unaware of this fact also, that the actual disease is that condition of the body which, not accidentally, but primarily and of itself, impairs the normal function. How, then, is he going to diagnose or cure diseases if he is entirely ignorant of what they are, and of what kind and number? As regards the stomach, certainly, Erasistratus held that one should at least investigate how it digests the food. But why was not investigation also made as to the primary originative cause of this? And, as regards the veins and the blood, he omitted even to ask the question how?
9
Yet neither Hippocrates nor any of the other physicians or philosophers whom I mentioned a short while ago thought it right to omit this; they say that when the heat which exists naturally in every animal is well blended and moderately moist it generates blood; for this reason they also say that the blood is a virtually warm and moist humour, and similarly also that yellow bile is warm and dry, even though for the most part it appears moist. (For in them the apparently dry would seem to differ from the virtually dry.) Who does not know that brine and sea-water preserve meat and keep it uncorruptedLit. aseptic., whilst all other water — the drinkable kind — readily spoils and rots it? And who does not know that when yellow bile is contained in large quantity in the stomach, we are troubled with an unquenchable thirst, and that when we vomit this up, we at once become much freer from thirst than if we had drunk very large quantities of fluid? Therefore this humour has been very properly termed warm, and also virtually dry. And, similarly, phlegm has been called cold and moist; for about this also clear proofs have been given by Hippocrates and the other Ancients.
