Disease is a departure from health. The first study of medicine—anatomy—gives us a knowledge of healthy structure. The second study of medicine—physiology—notes all the activities of this healthy structure under normal conditions, and gives us a standard of healthy function. From this standard of structure and function we make the measurement of disease.

It may be well to understand first of all, that the diseased man is in a worse condition than the well one. To the extent of his disease he is incapacitated for his work, and his sensations are painful instead of pleasurable. He loses his flesh, his strength, his functional activities, and is below his normal condition. He who fails to recognize that disease is a wrong life, and that impairment and debility are its essential features, has no business to practice medicine.

We say of the healthy man that he is able to do a man's work in the world, and do it pleasurably. We say of the healthy part, it is able to do the work of the part, and do it pleasurably. When a man can not do his work he is sick; to the extent that he can not do his work, is the gravity of his sickness. When his efforts to do the things he has been accustomed to are unpleasant or painful, he is sick, and the extent of the unpleasantness is frequently the measure of the disease. When an organ or part can not do its work, it is sick, and the extent of the impairment is the measure of the wrong. When an organ or part gives unpleasant or painful sensatious, it is sick, and these are also the measure of disease in some cases.

In thinking of disease as a wrong life, rather than something that has taken possession of a man—that he has caught, or that has caught him—we have made an important advance. It is his life that we have to deal with, and it is his life impaired. It is death that we meet in the sick chamber. To the extent and gravity of the disease, death is taking the place of life. Death comes in the impairment of structure and function; life comes with its restoration to the normal conditions. We should be conservers of the life, and to do this we should restore the conditions of health, in so far as we have control over them.

Thus we might write our first therapeutic axiom as follows: In disease there is always impairment of life, therefore remedies should always conserve the life, and increase the patient's power to resist disease, and regain his normal condition.

In our study of disease we do not forget that there may be a present cause which should be removed. We see a man crossing the street with a burthen, then slip and fall. He asks our assistance to rise, but he is weighed down with the load which has fallen on him. Will we pull his arms out in an effort to raise him? or curse him, kick him, and cuff him, to stimulate to renewed effort? Or will we lift off the load, and then give him a hand? It is a very homely simile, yet it presents the matter in a fair light.

A patient is suffering from diphtheria, smallpox or typhoid, in a dark, ill-ventilated room, or a house permeated by sewer gas. A person is developing a phthisis pulmonalis in a low, damp and dark locality. A patient is doing badly, with dirt, bad air, insufficient food, want of rest, etc. A man has grown a nervous dyspepsia and a dyspeptic nervousness by the abuse of tobacco. A woman is exhausting her little stock of life in frequent child-bearing or prolonged lactation. A woman or man is exhausting his or her little stock of life in marital excesses. People are exhausting their digestive powers and growing confirmed dyspepsia, by bolting their food without chewing. What shall be done with them? Which is the first step towards a cure? These are common examples, and every reader can multiply the instances given; and as he does, he will see clearly the necessity of removing the cause of the wrong. The causes of disease are many, and the means of removal are many, but to the thinking physician the problem soon solves itself.

If we found a patient with a thorn or splinter in his hand or foot, it would be good practice to remove it. If we find a worthless tooth a cause of persistent neuralgia, it is good practice to extract it. If we find a women suffering blood poisoning from a retained placenta, it is good practice to effect its removal. In the same way, if we find a patient suffering from unpleasant accumulations in the stomach, which are a source of irritation, and by decomposition cause blood poisoning, it is good practice to give an emetic and remove them. If a patient is suffering from accumulations in the bowels, a cathartic for removal is good practice. If, from arrested secretion of the skin, the blood contains effete material, a cause of disease, it is good practice to stimulate the skin to increased activity, and effect its removal. In like manner, if the kidneys fail to remove their part of the waste, and its retention is a cause of disease, diuretics are rational remedies.

The reader will see that these are the results of applied common sense—the sense we find best adapted to the ordinary affairs of life. The matter is plain to the simplest mind— there is a known cause of disease present, there are direct means for its removal, and with its removal the living body regains its normal condition. It is the load which prevents the man from rising; you take it off, and he is able to get up.

In other cases we do not remove the cause directly, but we neutralize it so that it is no longer noxious and disease-producing. In toxicology we might illustrate it by arsenical, lead, and oxalic acid poisoning. The patient has taken arsenious acid, we give him hydrated sesqui-oxide of iron, and in arseniate of iron we have lost the poison. The patient has been poisoned with lead, and we give iodide of potassium, and in iodide of lead we have lost the cause of disease. The patient has taken oxalic acid, and we give a preparation of lime, and with the change to oxalate of lime the injurious influences cease.

Our patient has ague or other periodic fever; we give quinine, which neutralizes the cause, and the fever ceases. He is influenced by a zymotic cause and has the evidences of blood poisoning; we give the proper anti-zymotic, and we arrest the process. The tongue is pallid and dirty, and we give sulphite of soda; it is red, and covered with a glutinous nastiness, we give sulphurous acid; it is red, dry, and brown, we give muriatic acid. The patient gives an unpleasant fetor, like decomposing flesh, and we give chlorate of potash. Or the tongue may be broad and pallid, showing acidity, and a solution of bicarbonate of potash gives relief. Or it may be deep or dusky-red, showing alkalinity, and an acid proves the remedy.

There are special causes of disease, for some of which we know the antidote or remedy, but for others it is yet unknown. I have named quinine for that which is usually known as malaria, and is marked by periodicity. Tincture of muriate of iron is quite as certain in some phases of erysipelas, and Rhus in other cases. Phytolacca meets the poison of diphtheria in the majority of cases. Sulphide of calcium for the condition of furuncular inflammation, or inflammation of cellular tissue with low grade of deposit.

The entire system of antiseptic surgery is based upon this principle. The atmosphere is loaded with germs which favor sepsis and putrescence, if they are not the cause of it. That a wound do well these germs must be excluded, or their putrescent activity destroyed by antiseptics. If, as in the olden time and now in minor wounds, the cut is bound up in its own blood, and as it were hermetically sealed, the process of repair goes on kindly. Or if a surgical operation is performed with antiseptic precautions, and covered with an antiseptic dressing, the repair goes on without disturbance.

If further investigations should prove that some diseases are due to these micro-organisms, as has been so stoutly affirmed, then the province of medicine will be to protect against the contagium, and employ means to destroy and remove the organisms.

The recent experiments of Koch would suggest antiseptic inhalations and respirators in phthisis, and in the lower grades of pneumonia, and we await further study to determine the advantages to be obtained in this way.

These are not the only examples that might be given, and it is well for the reader to look the entire field over carefully. He might think of syphilis and the syphilitic virus, which infects the lymphatic system and poisons the springs of the blood. For this we have as yet no antidote, though in the good time coming it will probably be found. An enlarged spleen may be the cause of imperfect blood making or of leucocythemia. A failure of the pancreas from low inflammatory action or change of structure, may so impair blood making and the nutritive processes that the person can not live. The virus of smallpox, scarlatina, whooping cough, typhoid and typhus fever, and other diseases of like character, must find antidotes in the future.

We may put the matter in the form of an axiom—If the cause of disease is present it should be removed or neutralized, unless such removal by remedies is more dangerous to the life of the patient than its continued presence.

Can we see in these methods a rational use of medicines, and that for the administration of every drug, and for every other procedure, we must have a reason? Why do we give an emetic in disease? Is it because it was given by Dr. Thompson, Dr. Beach, Dr. Jones, or some other man? O no! it is because in this particular case we see the evidences of unpleasant material in the stomach, which acts as a cause of disease. Smith is attacked with fever to-day, and we give him an emetic with most marked success. Thompson has a fever next week; shall we give him an emetic because it benefited Smith? Not unless he shows the same evidences in a broad and loaded tongue, and full, oppressed epigastrium.

Shall we give cathartics to all patients merely because they are so "highly recommended," and have been used with benefit by Wood, Pereira, Copeland, Jones, and others? Not by any means; we use a cathartic because in this particular case we have the evidence that there is something in the bowels which is a source of irritation and a cause of disease.

Shall we give quinine in all cases and in the extravagantly large doses that are recommended by nearly all the teachers of regular medicine? Not by any means; we give it because there is the distinct indication, periodicity; and if we do not find this indication, we do not give the medicine.

Shall we give morphine to relieve pain, because the mass of the profession use it so freely, or because writers testifiy that they "employ it with the greatest advantage", or it "has been found highly useful," etc. Not by any means; we prefer to look for the cause of the pain, and by getting rid of the condition of disease of which pain is a symptom, we get rid of the pain.

Our third axiom might therefore take this form—We do not use remedies because they have been "highly recommended" or have been found useful in named diseases, by writers or teachers of medicine; we use them because in the particular case there are evidences of disease calling for the particular remedy. We do not prescribe at names, but for conditions; we are not governed by authority, but by observation and the simple ruless of reason.

Having given some thought to the "cause" of disease, and the necessity of its removal, we may study the "effects" upon the human body. The relation between cuuse and effect is just as absolute in disease as elsewhere in nature. There is no effect without a sufficient cause, and there is no particular effect without its particular cause. It is true that what seems to be effect, does not always cease when the cause is withdrawn. An injury is done the structures of the body—and until complete repair has been effected, there can not be normal functional activity.

The derangements of structure and function following causes of disease are multiform, because the body that is impressed is a very complex structure. A recent writer, speaking of this, says of the head of a spermatozoon—if you will imagine this as large as the Great Eastern, and filled with machinery as delicate as the finest watch, you will only approximate the delicacy and complexity of structure. Organic forms are wonderful creations, and it is well to get a conception of them. Last night I had on the page of my book an insect so small that I strained my eyes to see it—the point of a pin would cover it, yet this creature had six legs, with five perfect articulations each, muscles to move them, antenna; more flexible and with a finer sense than an elephant's trunk, wings with powerful wing muscles, a skeleton, feathers, a complete digestive apparatus, a nervous system, and an apparatus of procreation. It is a fair example; think of every part of the human body as composed of a like minute and perfect structure. You have heard some mean persons' souls described as "that thousands of such might dance on the point of a cambric needle." Of the living molecules of the human body, millions might play in the same space.

But with our gross senses we can not take cognizance of the wrong of these minute structures. We may agree with Virchow, that all functional activity springs from cells, and that all abnormal life (disease) is due to wrong of the living cells. We may go further and agree with Grauvogl, that all life is due to the movements of the molecules of living matter, and disease must be due to changes of these molecules. But as they are so far beyond our senses, the knowledge is of no practical benefit.

Only this thought will suggest itself. If the basis of our tissues are thus minute, and the structures so fine and complex, is there good reason why we should rely upon such gross remedies, and such violent effects. Will a watch-maker repair a watch with a sledge-hammer.

Practically it serves our purpose better to divide the body into a few principal parts, having somewhat distinct functions, and study these. For a full consideration of this subject the reader is referred to my Principles of Medicine; here we will make but a brief synopsis of the subject.

The Forces of Life.—Having a body, it must be set in motion and kept running, for the motion is life. Movement necessitates force, and we have to learn how this body receives force from without, liberates it for its varied movements, and regulates it for its normal uses. This force is one, but as it manifests itself in different ways, it is of advantage to study it as formative force, heat, and electricity.

These forces are also conditions of life. The impulse (formative), from the parents, is to a certain extent the measure of the life of the child, both as to its activity and duration. A temperature of 98° is indispensable to healthy life—if it is increased, the person is sick. A certain amount of electricity is necessary to healthy life; if it is deficient there will be disease, if it is in excess there will be disease.

Measurement of Disease.—This brings us to the consideration of the common rule for the measurement of disease, and for the application of remedies. Disease is either an excess, defect, or perversion. There may be an excess of structure, defect of structure, or perversion of structure; an excess, a defect, or a perversion of any function.

If there is an excess, such remedies should be employed as will lessen or remove it. If there is a defect, such remedies are to be employed as will increase or restore it. If there is a perversion, such remedies are to be employed as will rectify and bring back to a normal condition.

The Conditions of Life.—It is a first duty of the physician to see that the conditions of life are right. A well man may live and even enjoy comfortable health under very bad conditions, because the human body has great adaptibility, and power of resisting unfavorable impressions. But the sick have lost this resisting power, and bad conditions of life may cause a disease to prove fatal that in other circumstances would terminate in health.

The first group of conditions are—light, air, exercise, food. If we use the prefix "good," we will express right conditions, as good light, good air, right exercise, good food. If these conditions are wanting, they must be obtained.

Division of Function—As we continue our study, we find that the organs of the body group themselves into a digestive apparatus, a blood-making apparatus, a respiratory apparatus, an excretory apparatus (skin, kidneys, bowels), an apparatus for reproduction, and a nervous system, an apparatus for innervation.

The selection of food, its preparation for use, its mastication, insalivation, gastric digestion, and intestinal digestion, is the study of the first, and a study that can not be too thoroughly made. The food is the life of the man. It furnishes the material for the continuous renewal of the body, without which the man would die, and it furnishes the force which gives activity to all parts of the body, and a surplus for the world's work.

The apparatus of blood-making is not as thoroughly studied as it should be. The lacteals, the mesenteric glands, the entire lymphatic system with its glands, the ductless glands (spleen, thyroid, thymus, and supra-renal capsules), the pancreas, and especially the liver, are all to be looked over in this study. Wrong of any part may cause a wrong of the blood, a wrong of nutrition, and a wrong of structure, with a still further wrong of function as a result.

The apparatus of respiration is essential to every moment of life. Stop it, and the life stops. Retard it, and the life is retarded. Impair it, and the life is impaired.

The excretory apparatus has offered therapeutists a fruitful field for study. The material of excretion is a tangible nastiness that impresses itself on the dullest minds. It looks bad, it smells bad, and without trying it one can readily say that it tastes bad, and it is something that people do not like to curry about their bodies, or come in contact with. Further than this, common experience has shown that it is disease-producing, whether retained in the blood, or re-absorbed after it has been excreted. There is nothing clearer than that this unpleasant matter should be removed from the blood, and we have large classes of remedies looking to this end.

The fact that human excretion is eminently poisonous when once out of the body, is not so well appreciated. True, people do not defecate or urinate in their clothing, but they sometimes do worse. They so arrange the place of deposit, that it filters into wells, cisterns, milk houses, cellars, and poisons springs and water courses. One would object if he saw his neighbor hang himself over the well-curb to defecate in the water, but the thing is done all the time, but in a more modest way. Human excreta in water, in milk (and the water cows drink), in food, is a common cause of diphtheria, typhoid fever, spotted fever, cerebro-spinal meningitis, Asiatic cholera, and the entire catalogue of zymotic disease. It is material to breed a pestilence.

The apparatus for reproduction and the perpetuation of the species, occupies a minor place in the study of medicine, but yet is one of great importance. It is at the bottom of many diseases of men, and the majority of the diseases of women.

What may we say of the apparatus of innervation further than it is nearly always at fault in disease. In some cases it gives the major wrong, in others it is secondary and small, but in all it needs to be studied with care. Through it we reach every part of the body, and can influence every function. With right innervation our patients readily recover, with wrong innervation they suffer and remain sick.

Structural Disease.—There must be change of structure for every wrong of function, but as before remarked we only notice the gross changes not the more minute ones. We find an increased nutrition, and a part or organ becomes too large, and we call it hypertrophy. We find an organ, part or the entire body, becoming too small, and we call it atrophy. Or we find the structures changing in quality or in form, and we call it perversion—degenerations, deposits, or growths.

I have made this brief review of the subject only to stimulate the reader to a thorough study of it. It furnishes the basis for a rational practice of medicine, stimulates to close observation, and to the careful use of remedies.

Expression of Disease.

It is a fact that disease has definite expression, which may be studied and learned. The same condition of disease will give the same expression, so that, having learned the language of disease, we have a certain guide in diagnosis. It will not be amiss in this connection to remind the reader of the absolute law that like causes produce like effects. If the symptom or expression is the effect, like symptoms must show like conditions.

It may be urged that the symptoms of disease are sometimes masked, or that the evidence of grave disease may be covered up by symptoms of minor wrongs (usually of the nervous system), or that patients and nurses may mislead the physician. This may be the case, but knowing the many deceptions which may lead him astray, the doctor guards himself against them. "He who is forewarned is thrice armed."

The common methods of diagnosis, which names diseases and classifies them, does not serve our purpose in therapeutics, however useful it may be in studying the natural history of disease. In this method the most diverse conditions of disease may be covered by the same name, and he who prescribes for or at names is sure to go wrong.

In modern therapeutics we associate certain remedies with certain expressions of disease, the remedy proving curative in such cases. Thus we say that a broad, pallid, and dirty tongue indicates a condition of disease which will be met by sulphite of soda; a dusky red, with brown coating, indicates a condition which will be met by muriatic acid; a bluish, full appearance of the face, like one who has been long exposed to cold, is met by baptisia; a pallid mucous membrane, with pultaceous or fibrinous deposit, is met by phytolacca; a small, frequent pulse is met by aconite; a full, frequent pulse is met by veratrum; a small, sharp pulse, with nervous hyperesthesia, is met by rhus; dullness, disposition to sleep, coma, dilated pupils, are met by belladonna; distinct periodicity in disease is met by quinine, etc., etc.

How this relation between disease expression and drug action has been determined might be made an interesting study, if we had time. Suffice it to say, that much of it has grown from the observation of the effects of medicine when given in the ordinary empirical way. Careful observers have noticed that in some cases the medicine was markedly curative, whilst in others it was not. They would remark some peculiarity or special symptom in the cases benefited, and would afterward give the medicine where that peculiarity or symptom was observed; and thus the relation between such expression or symptom and the drug, would be established. In other cases the relation has been established by careful experimentation on the sick. Some peculiar action of the drug, or some special want of the patient would suggest a particular drug. It would be used again and again, until the relation between disease expresssion and drug action was established. In still other cases the relation has been established by proving the remedy on healthy persons, and determining by this its quality of action, and its affinity for special parts. This is the homoeopathic method, and the law they insist upon is, similia similibus. But it is also the physiological method; for, the influence of a drug having been determined, as to its quality and selection of special organs, parts or functions for its action, the agent is employed when such action is required. A remedy being something which opposes disease, we are quite correct when we say it is antipathic. It is well to bear in mind that a remedy is a force which opposes disease. It may not seem so when we take the material in our hands, and to all our senses it seems inert. But locked up in its molecules is a wonderful power, sometimes in the smallest compass, which is sufficient to change the entire current of life, and make it flow in a different direction.

The American Eclectic Materia Medica and Therapeutics, 1898, was written by John M. Scudder, M.D.