August 9, 1900] 



NA TURE 



;57 



profession which it brings with it, is continued recurrence to 

 the scientific basis on which the practice of medicine rests. 

 Our art is most satisfactory and efficient when most closely 

 resting on science. The surgeon is continually guided by 

 anatomy and mechanics in dealing with injuries and deformi- 

 ties. The physician is often able to apply his knowledge of 

 chemistry and natural history to the direct and satisfactory 

 treatment of disease. In general, medical science justifies its 

 claim to the title by the same conclusive argument as astronomy 

 or chemistr}' — by its predictions coming true. In particular, 

 the detection and treatment of plumbism, the diagnosis and 

 cure of scabies and ringworm, the treatment of poisons by 

 chemical antidotes, and of specific diseases by attenuated 

 inoculations are all instances of strictly scientific medicine. 

 Nor can I refrain from citing the most recent and one of the 

 most remarkable advances of our science in the discovery of 

 the origin of malaria. This heavy tax upon national as well 

 as individual vigour and happiness has been known and treated 

 from the dawn of medicine ; but although by a happy accident 

 its efficient treatment was discovered, it is only lately that, by 

 the combined labours of scientific physicians — Frenchmen, 

 Italians, and our own countrymen — the origin of the disease 

 has been discovered, the mode of its transmission traced, the 

 diagnosis of its several forms established, and its prevention 

 brought within reasonable hope. 



We know that treatment of symptoms without a diagnosis 

 is always unsatisfactory, and frequently worse ; but we know also 

 that diagnosis must rest upon accurate knowledge of morbid 

 anatomy, and of the natural history of the disease. Scientific 

 medicine based on observation and experiment is always practical 

 as well ; but empirical medicine, whether based upon fanciful 

 speculation or working by blind rule of thumb, is the most 

 unpractical thing that can be. 



Preventive Medicine and Aetiology. — That important and 

 constantly-growing branch of medicine, which deals with 

 the prevention rather than the cure of disease, depends no 

 less upon science, for tracking the dependence of one event 

 upon another is the essence of inductive science. All efficient 

 measures for the preservation of health, whether by in- 

 dividuals or communities, rest upon exact knowledge of the 

 natural course of diseases. In fact, disease may be defined as the 

 reaction of the human organism under conditions which make 

 for its destruction. We must never forget that no irritant will 

 cause inflammation in a lifeless skin ; that no bacteria can pro- 

 duce fever without a nervous system to play upon ; that no 

 meal, however Gargantuan, and no potations, however deep, 

 can produce their wonted effect without a stomach to react. 

 The infection of small-pox, of diphtheria, or of tubercle exerts a 

 very different influence upon vaccinated or unvaccinated sub- 

 jects, upon one who has received and one who has not re- 

 ceived the prophylactic serum, upon an organism which is 

 predisposed to or refractory against the invasion of the enemy. 

 How closely natural science is related to preventive medicine is 

 shown by the history of Jenner, who was a naturalist, and of 

 Pasteur, who was a chemist. How dependent we are upon 

 science is well illustrated by the history of myxcedema. The 

 cretinoid condition in adults which was discovered by the clinical 

 acumen of Sir William Gull, unintentionally produced by the 

 surgical skill of Prof. Kocher, and reproduced in animals by 

 Mr. Horsley, is now cured by the eminently scientific method 

 due to Dr. Murray, of Newcastle, and to Dr. Hector Mackenzie, 

 of St. Thomas's Hospital. Such examples of accurate tracing 

 of causation by observation and experiment admonish us to give 

 up the perfunctory explanations which so often do duty for in- 

 vestigation. If we ascribe every inflammation to cold, and every 

 vague complaint to gout ; if we acquiesce in the popular as- 

 cription of disease to over-work, mental strain, and the nervous 

 tension of modern life, we shall make no progress in true 

 aetiology. I see many patients suffering from idleness — few, or 

 none, from hard work. " Nerve-prostration " from "worry" 

 and ' ' brain-tension " often proves a decent synonym for the 

 effects of gambling and drink. Modern life is easier, safer, and 

 smoother than it was a hundred years ago. Our young men 

 and maidens are healthier, stronger, better grown, less hysterical 

 and sounder in mind and body than their great-grandparents. I 

 venture to think that the duty of a physician is not to flatter the 

 self-love of neurotic patients, but to inspire fortitude, and to 

 prescribe regular and steady work as the best cure for a thousand 

 nervous ailments. 



NO. 1606, VOL, 62] 



As another point in scientific jetiology, allow me to warn 

 against the temptation to assume that because many diseases are 

 now proved to depend upon the presence of bacteria this must 

 be true of all. Science does not anticipate, but wails for proof. 

 We have complete scientific evidence, according to the criteria 

 so well formulated by Koch, of the absolute and constant cause 

 of anthrax, of relapsing fever, of tubercle, and several other dis- 

 eases in both men and animals ; but we must not forget the 

 preliminary difficulty of identifying the specific bacillus — as in 

 the case of enteric fever and diphtheria — nor the difficulty of 

 finding one of the lower animals which is susceptible to the 

 disease, as again in the case of typhoid fever and of cholera ; 

 nor the difficulty of the same anatomical and clinical conditions 

 being produced by different organisms, as in the case of pneu- 

 monia and ulcerative endocarditis. Moreover, while in some 

 diseases, which are undoubtedly infective and specific, no con- 

 stant pathogenic microbe has yet been determined — as in typhus, 

 measles, small pox, and syphilis — we have, on the other hand, 

 in the case of leprosy and of lupus, examples of disease un- 

 questionably specific and bacterial in origin, but very unlike 

 other infective maladies in their clinical course and natural 

 history. At present it is surely undesirable to speak of " the 

 undiscovered microbe of rheumatism." Science has to do with 

 proved facts alone, and our language should never outrun our 

 knowledge. 



Experiments in Scientific Medicine. — There is one aspect of 

 scientific medicine so important that it must not be omitted— 

 the necessity of experiments for the progress of pathology, and, 

 through it, for the prevention and cure of disease. It requires 

 no argument to convince any one who is the least acquainted 

 with the principles of inductive science that experiment is no 

 less necessary than observation. In physics and in chemistry 

 this is obvious and universally acted on. The same method is 

 indispensable for the progress of animal and vegetable physio- 

 logy, and to such practical applications of science as engineer- 

 ing, agriculture and medicine. Nor can experiments be 

 restricted to rare occasional and solemn occasions ; they must be 

 carried on in large numbers, by many diflTerent experimenters, 

 and under every variety of condition. Any attempt to abolish, 

 to check or to limit this experimental work is, in the degree 

 that it is successful, fatal to progress. Happily it can never be 

 successful, for the impulse to increase knowledge of the works of 

 creation is too deeply implanted in men. Investigation must 

 and will go on by the only path which it can follow. The 

 method which was preached by Bacon and followed out by his 

 great contemporary, William Harvey, which was continued by 

 Lower, Hooke and Mayow in the early days of the Royal Society, 

 by Aselli, Malpighi and Haller, by Hunter, Hewson and 

 Hales, by Edward Jenner, by Sir Charles Bell, by Johannes 

 Mliller, by Claude Bernard, by Ludwig, and by the many 

 eminent physiologists and pathologists in Germany, in France 

 and throughout the civilised world, this method of investigation 

 is absolutely necessary for the progress of our science and the 

 improvement of our art. As its objects and methods are better 

 understood, it will secure the enlightened patronage of all who 

 desire the diffusion of human knowledge and the further spread 

 of human happiness. Fortunately this very progress of sci ence 

 has brought with it the removal of the one grave drawback, as 

 every right-thinking man must have felt it, to the benefits of 

 these experiments upon living animals. Inflicting pain upon 

 the humblest of God's creatures is repugnant to our feelings, 

 though no one, unless maintaining a thesis, would contend that 

 it is wrong to exact the most painful efforts, or even the death 

 from exhaustion of a horse in order to carry help to a human 

 being. But the discovery of ether, chloroform, and other 

 anaesthetics, and the improved methods that we owe to the 

 genius of Lister, have not only relieved the surgeon of the most 

 repulsive part of his duties, but have relieved the experimenter 

 also. Except in the investigation of the action of new remedies 

 or in the inoculation of infective diseases, both of which inflict 

 discomfort of a limited degree and duration rather than any- 

 thing that can be described as pain, the experiments of the 

 laboratory, whether physiological, pathological or therapeutical, 

 are conducted without inflicting pain. The opposition to them 

 has not succeeded, and is sure to diminish. However mistaken 

 our opponents, we are glad to find there is even exaggerated 

 jealousy to avoid anything approaching to cruelty. This 

 legitimate object our more candid critics may be assured is 

 already amply provided for. 



