Читать книгу The Body at Work: A Treatise on the Principles of Physiology онлайн

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This comparison of anatomy and physiology must not be pushed too far. Enough has been said to emphasize the distinction between them. The one treats of form, the other of function. The one looks at structure, the other at action. Anatomy in its limited and logical sense has nothing to do with the uses of a part; its business is to measure it. Physiology has nothing to do with the measurements of parts; its duty is to watch for movement. Every living thing may be contemplated either in its statical or in its dynamical aspect. Physiology looks at it from the latter point of view.

Surveying his province, the physiologist asks himself: “Who are my subjects? What am I to find out about them? What methods, in addition to direct observation, may I use to obtain this information?” His oversight embraces all living things. It is no longer reasonable to make a distinction between human and animal physiology, or between the physiology of animals and the physiology of plants. No human being can take all science for his field. If he contents himself with scratching its surface, he will assuredly raise but a meagre crop, and that mostly weeds. But he is far behind the spirit of his age if he declines to sow in his own little patch seeds of thought which have blossomed in other localities, however remote. The man whose purpose in studying physiology is to obtain a knowledge of the working of the healthy human body, in order that he may know how to set right the accidents, perversions, and premature decay to which human flesh is prone, would remain an empiric of the most rigid type did he not apply to the elucidation of his problems all conclusions reached from the study of other organisms which are likely to prove pertinent. There would be no science of human physiology had observation and experiment been limited to Man. There would be no science of medicine, it may be added, had not the mode of working of the human body, and the influence of drugs upon it, been inferred from the results of experiments upon animals—experiments which could never have been made upon men. Blisters, blood-letting, mercury-poisoning, would still be the physician’s remedies for all human ills. “Give the watch a good shaking. It sometimes does good. If that fails, I cannot advise you what to do, as I know nothing about the working of a watch.” Even though we open the living human body, as must be done for the purpose of making good such defects as are amenable to surgical treatment, and for a little while observe its wheels go round, we are unable, from fear of damaging the wheels, to introduce the mechanical tests which would tell us how and why they revolve. The man must be allowed to recover with uninjured organs. But, thanks to anæsthetics, there is no test which may not be applied to a live animal with as much propriety as to a dead one. Anæsthetics abolish the distinction, in its ethical applications, between life and death, because we are under no obligation, as in the case of the human being, to allow an animal to recover. Many experiments upon animals will be recorded in this book, and since the book is intended for the general public, who have been singularly misled regarding the nature and methods of vivisection, an opportunity is taken thus early of insisting that anæsthetics have made all things, not only possible, but legitimate. It is unnecessary to commence the description of each experiment with the statement that the animal was first placed in a condition of complete anæsthesia, or to end it with the statement that it was destroyed before it had recovered from the effects of the anæsthetic. The reader may take these facts for granted. In discussing the propriety of operating upon a living but unconscious animal, we are playing a word game as old as Plato’s day. What is life? What is the relation of the personality to the animal machine which it occupies and operates? For a few minutes a heart removed from the body continues to beat. In a physiological sense it is alive, although the body from which it was removed is dead. Yet the personality does not reside in the heart, as many generations of philosophers believed. It is merely an accident that the body dies when the co-ordinating mechanism, the heart, ceases to pump blood through its vessels. Nor is the personality limited to the brain. Without the sense-organs which place the brain in relation with the body, and owing to the movements of the body—by which the sources of sensations of smell, sight, hearing are ascertained—with the world of which it forms a part, there would be no personality, no Ego. Is it, then, coextensive with the body which exhibits it? A soldier returning crippled from the wars does not finish out his days with his personality curtailed. We are no nearer than was Plato to a definition of life. Such a discussion soon takes us out of the realm of science. Science is limited to the sphere in which the whole is greater than the part. Take away consciousness, and personality ceases. Guarantee that consciousness shall never return. The animal is dead. When considering the propriety of vivisection we must regard life and consciousness as inseparable. There can be no question of right or wrong in regard to experiments on a dead animal, even though a sensitive mind, from association, shrinks from contemplating them. A person who dislikes the idea of dissecting a dead animal is influenced by purely subjective and personal considerations; nor is he prompted by sympathy with an unconscious animal when he recoils from the spectacle of its still moving organs. The term “vivisection” conveys too large a meaning. A negative term is needed, some word which will hold the emotion of pity in check. Pity is misplaced when devoted to the unconscious subjects of physiological experiment; and, happily for animals, as for Man, anæsthetics suspend conscious life. Only a person who has undergone a surgical operation can understand how resolutely the intellect declines to adopt as part of itself things which have not come within its own experience. The nurse’s testimony, that a long interval separated the placing of the mask upon the face and the commencement of that dull half-consciousness which gradually reawakened into interest in one’s surroundings cannot be set aside. The nurse says that during that interval knife, saw, and cautery were busy at their work. Her story is accepted, but it is not believed. All physiological operations are conducted under anæsthetics. In by far the larger number the experiment is continued until life terminates, under anæsthetics. The only ground upon which an objection to vivisection can be based is the ground that it involves the infliction of pain, and it is with regard to this that the greatest misapprehension exists in the public mind. Only in experiments which have for their object the study of the effects of the removal of a certain part, the diversion of a duct, the elimination of the control of a particular nerve, is there any possibility, under existing conditions, that an animal will suffer. In such experiments as these, observations cannot commence until after the animal has recovered. The operation is conducted under anæsthetics, and with the utmost precautions, to prevent any disturbance of the animal’s general health. The injury is in almost all cases of a comparatively limited nature, and it is certain that it involves very little pain to the animal when it has recovered from its anæsthesia, since, thanks this time to aseptic surgery, there is no inflammation or other secondary trouble.