Dogmatic school

Thessalus, the son, and Polybus, the son-in-law of Hippocrates, were the founders of this sect, c. 400 BC, which enjoyed great reputation, and held undisputed sway over the whole medical profession, until the establishment of the Empiric school.

The Dogmatic school held that it was necessary to be acquainted with the hidden causes of diseases, as well as the more evident causes, and to know how the natural actions and different functions of the human body take place, which necessarily assumes a knowledge of the interior parts.

It is impossible, they said, for people to know how to set about curing an illness unless they know what it comes from; since there is no doubt that they must treat it in one way, if diseases in general proceed from the excess or deficiency of one of the four elements, as some philosophers supposed; in another way, if all the malady lies in the humours of the body, as Herophilus thought; in another, if it is to be attributed to the respiration, according to the idea of Hippocrates (perhaps alluding to the De Flatibus, which is generally considered spurious); in another, if the blood excites inflammation by passing from the veins which are meant to contain it into the vessels that ought only to contain air, and if this inflammation produces the extraordinary movement of the blood that is remarked in fever, according to the opinion of Erasistratus; and in another, if it is by means of corpuscles which stop in the invisible passages and block up the way, as Asclepiades affirms to be the case.

As for the evident causes, which are such as can easily be discovered by anybody, and where one has only to know if the illness proceeds from heat or from cold, from having eaten too little or too much, etc., they said it was necessary to inform one's self of all of that, make on it the suitable reflections; but they did not think that one ought to stop there without going any further.

They said also, in regard to the natural actions, that it was necessary to know wherefore and in what manner we receive the air into our lungs, and why we afterward expire it; why food is taken into the body, how it is there prepared, and then distributed through every part of it; why the arteries are subject to pulsation; what is the cause of sleep, wakefulness, etc.