Physiologia Medica

But there are also other domestic examples of this ignorance in medical matters. For many hundreds of years, the powers of remedies were known only by their surface; it was not known from which part of their whole being they depended. Finally, others came along who, by opening up the whole, brought into the light the very different and contrary faculties of purgatives and alteratives within one and the same substance. They showed to the eye in which part Vinegar cooled and in which part it heated—being a participant in both faculties, a fact that Galen wondered at.

This same thing now happens in the teaching of Medicine, or the precepts of other disciplines and arts. These are usually discussed in such a way that, although they are set before the eyes and thought to be well understood, they are nonetheless not understood. For since the proposed end of all sciences is knowledge, or notice of the Subject, that itself ought to be achieved through causes alone, with effects or other accidents separated. When these causes are known, they pour such light into the mind of the knowers that, though they were previously blind to what was seen, taught, and known, they now—having removed the small clouds of ignorance arising from disposition original: "κατὰ διάθεσιν"—

—they see through what they did not know, and recognize the thing as something new made from the old, as if seeing it with the internal eyes of the mind. Indeed, natural things, things beyond nature, and things against nature are commonly numbered. Likewise, five parts are numbered—physiology, pathology, semiotics, therapeutics, and hygiene—which complete and fulfill the whole of Medicine. But because, like any other thing, the edifice of Medicine stands built from a framework of causes and accidents, and its knowledge comes only from those things of which the matter is composed, the medical things and parts should not only be numbered or named, but reduced to causes and accidents so they may be known; since the knowledge of things is from causes alone and nowhere else. Since our author has performed this accurately, skillfully, and ingeniously, not only in the division of the whole of Medicine but also in all the other precepts of physiology, and has snatched the prize from others, there is no doubt that the very same thing that has been said and repeated so often before by others will appear so evidently as something new to the minds of readers and students that they will candidly profess that they now finally truly know what they previously only had an opinion about. Among other things, he has pursued the Humors—especially the secondary ones—the Spirits, and the Actions, even those which, as natural things pertaining directly to physiology, are read as having been described by others by name only. He has done this so learnedly, so copiously, so elegantly and methodically, that in respect to these, he should be considered not to have "done what was already done" but to have been the first to dig out a most worthy...