2d. That all the great sects of the ancient philosophers held that the four elements, namely, fire, air, earth, and water, are transmutable into one another, being all of a homogeneous nature, and based on one common substratum, namely, the primary matter.
3d. That, by reasoning from observation and analogy, the ancient philosophers arrived at the conclusion that this primary matter is a substance devoid of all qualities and forms, but susceptible of all forms and qualities.
4th. That although certain of the philosophers, the contemporaries and predecessors of Hippocrates, appear to hold that some one of the elements, such as fire and water, was the original of all things, even these had an idea, although not expressed by them in a definite manner, of a first matter, which serves as a basis to all the elements.
5th. That these doctrines of the ancient philosophers, whether well founded or not, are countenanced by many eminent names in modern literature and philosophy.
6th. That the opinion generally entertained regarding the doctrines of the ancient philosophers on this subject is altogether erroneous.
THE WORKS OF HIPPOCRATES.
ON ANCIENT MEDICINE.
THE ARGUMENT.
Although, as stated in the second section of the Preliminary Discourse, the evidence in support of this treatise be unfortunately not such as clearly to establish its genuineness, all who read it with attention must admit that it is replete with important matters, and that if not the production of Hippocrates, it is not unworthy of his high reputation. Notwithstanding, then, that I am by no means so well convinced as M. Littré is, that the work is genuine, I have not hesitated to follow his example in placing it at the head of the list, as the nature of its contents is such as to form an excellent introduction to the study of the Hippocratic medicine.
It contains, as M. Littré remarks, a polemic, a method, and a system. The polemic is directed against those of his predecessors who had corrupted medicine by introducing hypotheses into it as the causes of disease, such as heat, cold, moisture, and dryness. These it will be seen that he combats with great force of argument and clearness of illustration. The philosophical dogmas to which he is supposed to refer in this place are those of the section of Pythagoreans, called the Eleatic, who would appear to have held nearly the same opinions as Pythagoras himself with regard to the elements.[355] But, in fact, as I trust I have clearly made out in the third section of the Preliminary Discourse, all the ancient philosophers held substantially the same opinion regarding the elements, although they did not all express themselves in the same terms. It is of little consequence, then, to attempt to find out what particular class of philosophers our author directs his attack against, it being sufficient to say that he decidedly condemns the practice of founding the rules of medical practice on hypothesis.[356] I may here remark, that the censure thus bestowed on hypothetical systems applies to modern times as well as to ancient, to those who proclaim theories by which, like Broussais, they account for all diseases upon figments which they call inflammations, and those who, like Cullen, attribute most diseases to spasms. We may rest assured, from the sensible observations which Hippocrates makes on this subject in the present work, that the causes of all diseases are realities, provided we could find them out, and that they are not vague abstractions, as the authors of these hypotheses suppose.