But first, there are a number of terms which we are in the habit of using in a vague though not unintelligible way, and which it is as well now to define. These terms are the tools with which we are to work, and the first thing is to sharpen them. It is nothing to us that they have been sharpened a thousand times before; they always get dull in the using, and every new workman has a right to carry them to the grindstone and sharpen them to suit himself.
Nature, in medical language, as opposed to Art, means trust in the reactions of the living system against, ordinary normal impressions.
Art, in the same language, as opposed to Nature, means an intentional resort to extraordinary abnormal impressions for the relief of disease.
The reaction of the living system is the essence of both. Food is nothing, if there is no digestive act to respond to it. We cannot raise a blister on a dead man, or hope that a carminative forced between his lips will produce its ordinary happy effect.
Disease, dis-ease,--disturbed quiet, uncomfortableness,--means imperfect or abnormal reaction of the living system, and its more or less permanent results.
Food, in its largest sense, is whatever helps to build up the normal structures, or to maintain their natural actions.
Medicine, in distinction from food, is every unnatural or noxious agent applied for the relief of disease.
Physic means properly the Natural art, and Physician is only the Greek synonyme of Naturalist.
With these few explanations I proceed to unfold the propositions I have mentioned.
Disease and death, if we may judge by the records of creation, are inherently and essentially necessary in the present order of things.
A perfect intelligence, trained by a perfect education, could do no more than keep the laws of the physical and spiritual universe. An imperfect intelligence, imperfectly taught,--and this is the condition of our finite humanity,--will certainly fail to keep all these laws perfectly. Disease is one of the penalties of one of the forms of such failure. It is prefigured in the perturbations of the planets, in the disintegration of the elemental masses; it has left its traces in the fossil organisms of extinct creations. [Professor Agassiz has kindly handed me the following note: "There are abnormal structures in animals of all ages anterior to the creation of mankind. Malformed specimens of Crinoids are known from the Triassic and Jurassic deposits. Malformed and diseased bones of tertiary mammalia have been collected in the caverns of Gailenreuth with traces of healing."]
But it is especially the prerogative, I had almost said privilege, of educated and domesticated beings, from man down to the potato, serving to teach them, and such as train them, the laws of life, and to get rid of those who will not mind or cannot be kept subject to these laws.
Disease, being always an effect, is always in exact proportion to the sum of its causes, as much in the case of Spigelius, who dies of a scratch, as in that of the man who recovers after an iron bar has been shot through his brain. The one prevalent failing of the medical art is to neglect the causes and quarrel with the effect.
There are certain general facts which include a good deal of what is called and treated as disease. Thus, there are two opposite movements of life to be seen in cities and elsewhere, belonging to races which, from various persistent causes, are breeding down and tending to run out, and to races which are breeding up, or accumulating vital capital,--a descending and an ascending series.
Let me give an example of each; and that I may incidentally remove a common impression about this country as compared with the Old World, an impression which got tipsy with conceit and staggered into the attitude of a formal proposition in the work of Dr. Robert Knox, I will illustrate the downward movement from English experience, and the upward movement from a family history belonging to this immediate neighborhood.
Miss Nightingale speaks of "the fact so often seen of a great-grandmother, who was a tower of physical vigor, descending into a grandmother perhaps a little less vigorous, but still sound as a bell, and healthy to the core, into a mother languid and confined to her carriage and house; and lastly into a daughter sickly and confined to her bed." So much for the descending English series; now for the ascending American series.
Something more than one hundred and thirty years ago there graduated at Harvard College a delicate youth, who lived an invalid life and died at the age of about fifty. His two children were both of moderate physical power, and one of them diminutive in stature. The next generation rose in physical development, and reached eighty years of age and more in some of its members. The fourth generation was of fair average endowment. The fifth generation, great-great- grandchildren of the slender invalid, are several of, them of extraordinary bodily and mental power; large in stature, formidable alike with their brains and their arms, organized on a more extensive scale than either of their parents.