CHAPTER II.THE PROCESS OF DEATH.
Constitution of organisms.—Partial lives.—Collective life.—The rôle of apparatus.—Death by lesion of the major apparatus.—The vital tripod.—Solidarity of the anatomical elements.—Humoral solidarity.—Nervous solidarity.—Independence and subordination of the anatomical elements.
Partial Lives.Collective Life.—With the exception of the physiologist, no one, neither he who is ignorant nor he who is intellectual, nor even the doctor, troubles his head about the life or the death of the element, although this is the basis, the real foundation, of the activity manifested by the social body and by its different organs. The life of the individual, of the animal, depends on these elementary partial lives just as the existence of the State depends upon that of its citizens. To the physiologist, the organism is a federation of cellular elements unified by close association. Goethe compared them to a “multitude”; Kant to a “nation”; and others have likened them to a populous city the anatomical elements of which are the citizens, and which possesses an individuality of its own. So that the activity of the federated organism may be discussed in each of its parts, and then it iselementary life, or in its totality, and then it isgeneral life. Paracelsus and Bordeu had a glimpse of this truth when they considered a life appropriate to each part (vita propria)and a collective life, the life of the whole (vita communis). In the same way we must distinguish theelementary death, which is the cessation of the vital phenomena in the isolated cell, from thegeneral death, which is the disappearance of the phenomena which characterised the collectivity, the totality, the federation, the nation, the city, the whole in so far as it is a unit.
These comparisons enable us to understand how general life depends on the partial lives of each anatomical citizen. If all die, the nation, the federation, the total being clearly ceases to exist. This city has an enormous population—there are thirty trillion cellules in the body of man; it is peopled with absolutely sedentary citizens, each of which has its fixed place, which it never leaves, and in which it lives and dies. It must possess a system of more or less perfect arrangements to secure the material life of each inhabitant. All have analogous requirements: they feed very much the same; they breathe in the same way; each in fact has its profession, industry, talents, and aptitudes by which it contributes to social life, and on which, in its turn, it depends. But the process of alimentation is the same for all. They must have water, nitrogenous materials and analogous ternaries; the same mineral substances, and the same vital gas, oxygen. It is no less necessary that the wastes and the egesta, very much alike in every respect, should be carried off and borne away in discharges arranged so as to free the whole system from the inconvenience, the unhealthiness, and the danger of these residues.
Secondary Organization in Organs.—That is why, as we said above, the secondary organizations of theeconomy exist:—the digestive apparatus which prepares the food and enables it to pass into the blood, into the lymph, and finally into the liquid medium which bathes each cell and constitutes its real medium; the respiratory apparatus which imports the oxygen and exports the gaseous excrement, carbonic acid; the heart and the circulatory system which distributes through the system the internal medium, suitably purified and recuperated. The organization is dominated by the necessities of cellular life. This is the law of the city, to which Claude Bernard has given the name of thelaw of the constitution of organisms.
Death by Lesion of the Major Organs. Vital Tripod.—Thus we understand what life is, and at the same time what is the death of a complex living being. The city perishes if its more or less complicated mechanisms which look after its revictualling and its discharge are seriously affected at any point. The different groups may survive for a more or less lengthy period, but progressively deprived of the means of food or of discharge, they are finally involved in the general ruin. If the heart stops, there is a universal famine; if the lungs are seriously injured, we are asphyxiated; if the principal organ of discharge, the kidney, ceases to perform its allotted task, there is a general poisoning by the used-up and toxic materials retained in the blood.
We understand how the integrity of the major organs,—the heart, the lungs, the kidney,—is indispensable to the maintenance of existence. We understand that their lesion, by a series of successive repercussions, involves universal death. We always die, said the doctors of old, because of the failure ofone of these three organs, the heart, the lungs, or the brain. Life, they said in their inaccurate language, depends upon these as upon three supports. Hence the idea of thevital tripod. But it is not only this trio of organs which maintain the organism; the kidney and the liver are no less important. In different degrees each part exercises its action on the rest. Life is based in reality on the immense multitude of living cells associated for the formation of the body; on the thirty trillion anatomical elements, each part is more or less necessary to all the rest, according as the bond of solidarity is drawn more or less closely in the organism under consideration.
Death and the Brain.—There are indeed more noble elements charged with higher functions than the rest. These are the nervous elements. Those of the brain preside over the higher functions of animality, sensibility, voluntary movement, and the exercise of the intellect. The rest of the nervous system forms an instrument of centralization which establishes the relations of the parts one with the other and secures their solidarity. When the brain is stricken and its functions cease, man has lost the consciousness of his existence. Life seems to have disappeared. We say of a man in this plight that he no longer lives, thus confusing general life with the cerebral life which is its highest manifestation. But the man or the animal without a brain lives what may be called a vegetative life. The human anencephalic foetus lives for some time, just as the foetus which is properly formed. Observation always shows that this existence of the other parts of the body cannot be sustained indefinitely in the absence of that of the brain. By a series of impulses due to the solidarity of thegrouping of the parts, the injury received by the brain affects by repercussion the other organs, and leads in the long run to the arrest of elementary life in all the anatomical elements. The death of the whole is then complete.
Doctors have therefore a two-fold reason for saying that the brain may cause death. The death of the brain suppresses the highest manifestation of life, and, in the second place, by a more or less remote counter stroke, it suppresses life in all the rest of the system.
Death is a Process.—Besides, the fact is general. The death of one part always involves the death of the rest—i.e., universal death. A living organism cannot be at the same time alive and a cemetery. The corpses cannot exist side by side with the living elements. The dead contaminates the living, or in some other way involves it in its ruin. Death is propagated; it is a progressive phenomenon which begins at one point and gradually is extended to the whole. It has a beginning and a duration. In other words, the death of a complex organism is a process. And further, the end of a simple organism, of a protozoan, of a cell, is itself a process infinitely more shortened.
The very perfection of the organism is therefore the cause of its fragility. It is the degree of solidarity of the parts one with another which involves the one set in the catastrophe of the rest, just as in a delicate piece of mechanism the derangement of a wheel brings nearer and nearer the total breakdown. The important parts, the lungs, the heart, the brain, suffer no serious alteration without the reflex being felt throughout. But there are also wheels less evident, the integrity of which is scarcely less necessary.
The Solidarity of the Anatomical Elements.—The cause of the mortal process—i.e., of the extension and the propagation of an initial destruction—is therefore to be found in the solidarity of the parts of the organism. The closer it is the greater do the chances of destruction become, for the accident which has happened to one will by repercussions affect the others.
Now the solidarity of the parts of the organism may be carried out in two ways; there is ahumoral solidarityand anervous solidarity.
Humoral Solidarity.—Humoral solidarity is realized by the mixture of humours. All the liquids of the organism which have lodged in the interstices of the elements and which soak the tissues, are in contact and in relation of exchange one with another, and through the permeable wall of the small vessels they are in relation with the blood and the lymph.
All the liquid atmospheres which surround the cells and form their ambient medium have intercommunication. A change having taken place in one cellular group, and therefore in the corresponding liquid, modifies the medium of the further or nearer groups, and therefore these groups themselves.
Nervous Solidarity.—But the real instrument of the solidarity of the part is the nervous system. Thanks to it in the living machine the component activities of the cellular multitude restrain and control one another. Nervous solidarity makes of the complex being not a mob of cells, but a connected system, an individual in which the parts are subordinated to the whole and the whole to the parts; in which the social organism has its rights just as the individual has his rights. The whole secret of the vital functional activity of thecomplex being is contained in these two factors:—the independence and the subordination of the elementary lives. General life is the harmony of the elementary lives, their symphony.
Independence and Subordination of the Anatomical Elements.—The independence of the anatomical elements results from the fact that they are the real depositaries of the vital properties, the really active components. On the other hand the subordination of the parts to the whole is the very condition of the preservation of form in animals and plants. The architecture which is characteristic of them, the morphological plan which they realize in their evolutive development which they are ever preserving and repairing, form a striking proof of this. This dependence in no way contradicts the autonomy of the elements. For when with Claude Bernard and Virchow we study the circumstances we see that the element accommodates itself to the organic plan without violence to its nature. It behaves in its natural place as it would behave elsewhere, if elsewhere it were to meet around it the same liquid medium which at once is a stimulant and a food. This at least is the conclusion we may draw from experiments on transplanting, or on animal and vegetable grafting. Neither the neighbouring elements, nor the whole system act on it at a distance by a kind of mysterious induction, according to the ideas of the vitalists, in order to regulate the activity of the element. They contribute solely to the composition of the liquid atmosphere which bathes it. They intervene in order to provide it with a certain environment whose very characteristic physical and chemical constitution regulates itsactivity. This constitution may be some day imitated by the devices of experiment. When that result is achieved the anatomical element will live in isolation exactly as it lives in the organic association, and the mysterious bond which causes its solidarity with the rest of the economy will become intelligible. In fact, we may defer more or less the maturity of this prophecy, but there is no doubt that we are daily nearing its fulfilment.
The general life of the complex being is therefore the more or less perfect synergy, theordered processof elementary lives. General death is the destruction of these partial lives. The nervous system, the instrument of this harmony of the parts, represents the social bond. It keeps most of the partial elements under its sway, and is thus the intermediary of their relations. The closer this dependence, the higher the development of the nervous apparatus, and the better, also, is assured the universal solidarity and therefore the unity of the organism. Cellular federation assumes the characteristic of a unique individuality in proportion to the development of this nervous centralization. With an ideal perfect nervous system the correlation of the parts would also attain perfection. As Cuvier said: “None could experience change without a change in the rest.”
But no animal possesses this extreme solidarity of the parts of the living economy. It is a philosopher’s dream. It is the dream of Kant, to whom the perfect organism would be “a teleological system,” a system of reciprocal ends and means, a sum total of parts each existing for and by the rest, for and by the whole. An organism so completely connected would be unlikely to live. In fact, living organisms show alittle more freedom in the interplay of their parts. Their nervous apparatus fortunately does not attain this imaginary perfection; their unity is not so rigorous. The idea of individuality, of individual existence, is therefore not absolute but relative. There are all degrees of it according to the development of the nervous system. What the man in the street and the doctor himself understand by death is the situation created by the stopping of the general wheels, the brain, the heart, and the lungs. If the breath leaves no trace on the glass held to the mouth, if the beating of the heart is no longer perceptible by the hand which touches or the ear which listens, if the movement and the reaction of sensitiveness have ceased to be manifest, these signs make us conclude that it is death. But this conclusion, as we have said before, is a prognostic rather than a judgment of fact. It expresses the belief that the subject will certainly die, and not that it is from this moment dead. To the physiologist the subject is only on the way to die. The process has started. The only real death is when the universal death of all the elements has been consummated.