Xavier Bichat

“ The blood contains the materials of all the secretions, of the nutrition of all the organs, and of all the exhalations. Each gland draws from this common reservoir what is necessary to its secretion, as each organ does what is proper for its nutrition, and as each serous surface does what is suitable for its exhalation. Now it is by its organic sensibility that each living part of the body distinguishes what its functions require. ”

“ Man, who opposes nature in every thing, has made it a habit in most societies to cut the hair, the beard, &c. By common people, it is considered merely a thing of fashion; by the physician, as a practice which has perhaps a greater influence than is thought upon the functions. In fact, in the natural state when the pilous system has once acquired its growth, it no longer exhibits the constant motion of composition and decomposition. On the contrary, in man who cuts it, it is constantly the seat of this motion and of that of growth. ”

“ The mane of the lion becomes erect, the whole skin of the horse moves, a thousand different agitations animate the exterior of the trunk of animals, and make it a general picture on which is painted all that passes in the interior. You can determine from behind, in many animals, by seeing only their bodies, that they are agitated with passion; cover the face of man, the curtain is drawn over the mirror of his mind ”

“ Habit which accustoms us to every thing, changes our taste in regard to the colour of the hair, as it does to that of our dress. Black, flaxen and their numerous shades are in turns fashionable in France; and as the organization does not change with our taste, we have contrived artificial hair; a happy means, which seems to subject to our inconstancy the invariable course of nature, and which, changing at our will the expression which the physiognomy borrows from the hair, can at every instant exhibit man under forms which fashion extols to day, and which ridicule pursues tomorrow. ”

“ DERMOID SYSTEM.
All animals are covered with a more or less compact membrane, of a thickness in general proportioned to the size of their body, destined to defend the subjacent parts, to carry out a considerable portion of the residue of nutrition and digestion, and to place it in relation with external bodies. It is in man a sensitive boundary, placed at the extremity of the domain of his mind, where these bodies continually touch, for the purpose of establishing the relations of his animal life, and of thus connecting his existence with that of every thing which surrounds him. ”

“ Is the life of the glandular system more active in man than in woman? As it respects the glands destined to digestion, the secretion of the tears, the evacuation of urine, &c. there is but little difference in the two sexes. As to genital glands, man has testicles and the prostate; woman has mammæ, so that in this respect they seem to be equal. Observe however that the influence of the first upon the economy, is much greater than that of the second. It is from the womb that go forth in woman the irradiations which correspond with those which the testicles send to all the other organs. ”

“ We can hardly consider in a general manner the forms of the system of which we are treating; each organ belonging to it is moulded upon the form of the viscus to the formation of which it contributes. In fact, the organic muscles do not exist in distinct fasciculi, like those of animal life; all, except the heart, form but a third, a quarter and often even less in the structure of a viscus. ”

“ Now if fear acts so powerfully upon the hair, if it can give it a real motion, is it astonishing that grief and pain should suddenly change the fluids that are found in it, and deprive it even of these fluids? ”

“ We have carried this habit into the study of the living economy, without considering that it incessantly varies its phenomena, that under the same circumstances they are hardly ever the same, that they are continually increased and diminished and have a thousand different modifications. Nature seems at every instant to be irregular, capricious and inconsequent in their production, because the essence of the laws which preside over these phenomena, is not the same as that of the physical laws. ”

“ By approaching the fire then we do not become warm, because we really were not cold; but we only destroy by a real sensation, the opposite sensation which is illusory that we experience, or rather we turn the perception from this sensation. We know that at the instant of the ejaculation of semen, a sudden and sympathetic chill often extends over the body. We know the cold of fear, which almost always arises, like the sweat produced by this passion, from the sympathetic action exerted upon the cutaneous organ by an epigastric organ affected by the passion. ”

“ Hence why the salivary glands do not secrete bile, and the liver allows the materials of urine to pass in its vessels without separating them; from this results the diversity of secretions. Hence also why cantharides affect exclusively the kidneys; why mercury acts especially upon the salivary glands; why certain substances affect the testicles in a peculiar manner, increase their secretion and even promote the excretion of the semen; why some aliments give more milk than others. I am persuaded that certain substances act upon the mucous glands and dispose them to a greater secretion. ”

“ Now among these numberless variations which succeed each other among us in the fashion of the hair, bright red and its various shades never find a place. Most people have a decided aversion to it. It is almost, in our eyes, a mal-formation to be born with it. ”

“ Nature has wished in physiology, that the phenomena over which it presides, should be slowly connected; it is the same in morals. The woman who suddenly changes her dress from one that is close to one that is not, exposes herself to painful sensations, to catarrhal diseases, &c. and shocks the eyes of those who had been accustomed to see her in a different exterior. When the change is gradually and insensibly brought about, neither health nor morals are affected.
Habit does not modify the cutaneous sensibility which arises from an alteration of texture, from an inflammation, &c. ”

“ I have often raised up in many places the epidermis of an old person; it has not appeared to me to differ much from that of the adult; it is a little more subject to scale off and it is a little thicker. In some miserable objects which come to hospitals, there is often vermin in cracks of the epidermis, whose layers are afterwards separated by them and in which they live; so that I have seen the epidermis in this way conceal thousands of little animals, which were evidently found between the layers of this membrane, and which were not upon the reticular body and the papillæ. ”

“ The animal sensibility of the skin sometimes diminishes and even disappears; paralysis is a proof of this. These affections, more rare than the loss of motion, often however take place. In the organs of the senses, it is the eye which most frequently loses the sensation; the ear comes next, then the skin, then the nostrils and finally the tongue, which is the sensitive organ that is always most rarely paralyzed, no doubt because it is that which is the most connected with the support of organic life, without which we could not exist. ”

“ Another very evident proof that all the mucous fluids are designed to be thrown out, is, that when they have continued for some time in any quantity upon their respective surfaces, they create there a painful sensation of which nature relieves us by various means. Thus the cough, which is the constant result of an accumulation of mucus in the bronchia, serves to expel it; thus vomiting in gastric derangements answers the same purpose as it respects the mucous juices accumulated in the stomach, whose presence produces a weight and even pain, though the membranes be not affected. ”

“ We have observed two very distinct periods in the growth of the other muscles; one is finished when they have acquired their length; the other, when their thickness is complete. The first has not, in the organic system, a term as distinct; when the stature no longer increases, the gastric and urinary organs, and the heart still lengthen and grow.
We have considered growth in too general a manner. Each system has a different term in this great phenomenon. The osseous and muscular systems of animal life, and those which depend on them, as the fibrous, the cartilaginous, &c. ”

“ The increase of the action of the heart may depend no doubt upon a foreign substance, which, mixed with the blood, alters and renders it more irritating; it may be owing to an affection of the substance of the organ which disposes it to be more irritable; but it is certainly very often sympathetic, and depends upon that unknown relation which connects all our organs, upon that consensus which links together all their actions, and places them in reciprocal dependance. ”

“ The mucous juices are dissolved like every other fluid; for wherever there is atmospheric air, heat and moisture, there is evaporation. Here this evaporation is even a means which nature employs to rid herself, as I have said, of the mucous juices. If they are too abundant, as in a cold, then the quantity of air which serves as a vehicle to them, not increasing in proportion, it is necessary that there should be another mode of evacuation; this is expectoration which compensates for what the air cannot remove by solution. ”

“ This phenomenon of the organic muscles as it were surviving the voluntary in the last periods of life, is derived on a great scale from the same principle from which arises on a small one the lassitude which follows the contraction in an insulated motion. A less durable motion is necessary to fatigue the voluntary muscles, than to fatigue the involuntary; the stomach empty remains for a long time contracted upon itself without producing any painful sensation, whilst if we hold a body strongly grasped between our fingers for a quarter of an hour, all the flexors are soon painfully affected. ”

“ External life is then, in this respect, more limited in them than in man, in whom a delicate epidermis and a few hairs thinly scattered over it, separate the organ of feeling from surrounding objects, the least impression of which is felt, and which, owing to this, keep the animal sensibility in permanent activity; thus man is designed to live more without than within himself. The pleasures of reproduction and digestion constitute exclusively the happiness of animals. That of man is in part the result of them ”

“ If the skin and the mucous surfaces were always kept at the same degree of excitement by the constant uniformity of the stimuli, they would certainly be a much less fruitful source of diseases, as is clearly proved by the fœtus, which is hardly ever sick, because all the external causes which act upon its mucous and cutaneous sensibility, as the heat, the waters of the amnios and the parietes of the womb, do not vary until birth. At this period, animals brought into a new medium, find many more varieties in the stimuli which act upon them, even in a natural state and far from society ”

“ Many physiologists have spoken of a general convulsion which comes on in the organic muscles at the instant of death, of a rising of the heart, the stomach, the intestines, &c. This excess of action is sometimes real in sudden deaths, in those especially that we produce for our experiments; it is very rare in deaths preceded by a long disease in which the patient is extinguished, as it were, insensibly, and passes gradually from life to death. It is a fault common to almost all authors, to generalize too much the facts observed under certain circumstances. ”

“ We attach the idea of a beautiful skin, to that in which these small tubercles are not found, and in which the chorion is united at its external surface. Women have commonly this last arrangement more evident than men. The epidermis which covers these eminences very often scales off at that place, especially from strong friction, which contributes still more to render the skin uneven, rough and harsh to the touch where they exist, which might induce a belief that they are formed by it, though it is always only accessory to them. ”

“ We know that a short time before sleep, external bodies produce but an obscure sensation upon it, and that their contact has no effect in this state, in which animals seem to lose half of their existence. The more powerfully the cutaneous sensibility has been excited, the more profound is sleep; hence why all painful exercises, great frictions, &c. are always followed by a deep sleep. Yet this sense can sometimes exert itself, while the others sleep; pinch the leg of a man asleep; he draws it away without waking, and has afterwards no remembrance of the sensation. ”