1st. It is not proven.
2nd. It is not true.
Take the so-called fever. The immediate and most frequent causes of fever are bad air, unwholesome food, mental inquietude, derangement of the digestive organs, severe injuries. Now it is notorious that very important agents in the cure of all fevers are good air, carefully exact diet or temporary abstinence, and correction of disordered functions, with utmost repose of mind and body, and so forth.
So of small-pox, one of the most instructive of all diseases. All the things favourable to small-pox are entirely opposite to those which conduct the patient safely through this alarming disease; and so clearly is this the case, that, if known beforehand, its virulence can be indefinitely moderated, so as to become a comparatively innoxious malady.
We might go on multiplying these illustrations to almost any extent. What, then, is the meaning of the similia similibus curantur? This we will endeavour, so far as there is any truth in it, to explain. The truth is, that Nature has but one mode, principle, or law, in dealing with injurious influences on the body. Before we offer the few hints we propose to do on these subjects (and we can here do no more), we entirely repudiate that sort of abusive tone which is too generally adopted. That never can do anybody any good. We believe both systems to be dangerous fallacies; but, like all other things, not allowed to be entirely uncharged with good. We shall state, as popularly as possible, in what respect we deem them to be dangerous fallacies, and in what we deem them to be capable of effecting some good; because it is our object to show, in respect to both, that the good they do is because they accidentally, as it were, chip off a small corner of the principles of Abernethy.
Homœopathy is one of those hypotheses which show the power that a minute portion of truth has to give currency to a large quantity of error; and how much more powerful in the uninformed are appeals to the imagination than to the intellect. The times are favourable to homœopathy. To some persons, who had accustomed themselves to associate medical attendance with short visits, long bills,—a gentleman in black, all smiles,—and a numerous array of red bottles, homœopathy must have addressed itself very acceptably. It could not but be welcome to hear that all the above not very pleasing impressions could be at once dismissed by simply swallowing the decillionth part of a grain of some efficacious drug. Then there was the prepossession so common in favour of mystery. How wonderful! So small a quantity! What a powerful medicine it must be! It was as good as the fortune-telling of the gipsies. There! take that, and then you will see what will happen next! Then, to get released from red bottles tied over with blue or red paper, which, if they were not infinitesimal in dose, had appeared infinite in number, to say nothing of the wholesome repulsion of the palate.
Besides, after the bottles, came the bill, having no doubt the abominable character of all bills, which, by some law analogous to gravitation, appear to enlarge in a terrifically accelerating ratio, in proportion to their longevity; so that they fall at last with an unexpected and a very unwelcome gravity. Then homœopathy did not restrict itself to infinitesimal doses of medicine, but recommended people to live plainly, to relinquish strong drinks, and, in short, to adopt what at least seemed an approximation to a simple mode of living. To be serious—what, then, are the objections to homœpathy?
Is there no truth, then, in the dogma, "Similia similibus curantur?" We will explain. The laws governing the human body have an established mode of dealing with all injurious influences, which is identical in principle, but infinitely varied and obscured in its manifestations, in consequence of multifarious interferences; in that respect, just like the laws of light or of gravitation. As we have no opportunity of going into the subject at length, we will give a hint or two which will enable the observing, with a moderate degree of painstaking, to see the fallacy. You can demonstrate no fallacy in a mathematical process even, without some work; neither can you do so in any science; so let that absence of complete demonstration be no bar to the investigation of the hints we give. All medicines are more or less poisons; that is, they have no nutritive properties, or these are so overbalanced by those which are injurious, that the economy immediately institutes endeavours for their expulsion, or for the relief of the disturbance they excite. All organs have a special function of their own, but all can on occasions execute those of some other organ. So, in carrying out injurious influences, organs have peculiar relations to different forms of matter; that is, ordinarily. Thus, the stomach is impatient of ipecacuanha, and substances which we call emetics; the liver, of mercury, alcohol, fat, and saccharine matters; and so forth. In the same way we might excite examples of other organs which ordinarily deal with particular natural substances. But then, by the compensating power they have, they can deal with any substance on special occasions.
Now the natural mode in which all organs deal with injurious substances, or substances which tend to disturb them, is by pouring forth their respective secretions; but if, when stimulated, they have not the power to do that, then they evince, as the case may be, disorder or disease. Thus, for example: If we desire to influence the secretion from the liver, mercury is one of the many things which will do it. But if mercury cease to do this, it will produce disease; and, if carried to a certain extent, of no organ more certainly than the liver. Thus, again, alcohol, in certain forms, is a very useful medicine for the liver; yet nothing, in continuance, more notoriously produces disease of that organ. So that it happens that all things, which in one form disorder an organ, may, in another form, in greater or more continued doses, tend to correct that disorder, by inducing there a greater, and thus exciting stimulation of its secretions.
This is the old dogma, long before homœopathy was heard of, of one poison driving out another. This is the way in which fat bacon, at one period, or in one case, may be a temporary or a good stimulant of a liver which it equally disorders in another; for as the liver is a decarbonizing agent, as well as the lungs, so articles rich in carbon are all stimulants of that organ; useful, exceptionally; invariably disordering, if habitual or excessive.