Read Ebook: The Heart's Domain by Duhamel Georges Brooks Eleanor Stimson Translator

Font size: 10 px 15 px 20 px 25 px 30 px 35 px

Background color: BlackWhiteGrayLight GrayDark GrayDim Gray

Text color: BlackWhiteGrayLight GrayDark GrayDim Gray

Apply/Save settings

Ebook has 793 lines and 49899 words, and 16 pages

CHAP. PAGE

INDEX 365

FIG. PAGE

FORM AND FUNCTION

THE BEGINNINGS OF COMPARATIVE ANATOMY

The first name of which the history of anatomy keeps record is that of Alcmaeon, a contemporary of Pythagoras . His interests appear to have been rather physiological than anatomical. He traced the chief nerves of sense to the brain, which he considered to be the seat of the soul, and he made some good guesses at the mechanism of the organs of special sense. He showed that, contrary to the received opinion, the seminal fluid did not originate in the spinal cord. Two comparisons are recorded of his, one that puberty is the equivalent of the flowering time in plants, the other that milk is the equivalent of white of egg. Both show his bias towards looking at the functional side of living things. The latter comparison reappears in Aristotle.

A century later Diogenes of Apollonia gave a description of the venous system. He too placed the seat of sensation in the brain. He assumed a vital air in all living things, being in this influenced by Anaximenes whose primitive matter was infinite air. In following out this thought he tried to prove that both fishes and oysters have the power of breathing.

A more strictly morphological note is struck by a curious saying of Empedocles , that "hair and foliage and the thick plumage of birds are one."

The author of the treatise "On the Joints," which Littr? calls "the great surgical monument of antiquity," is to be credited with the first systematic attempt at comparative anatomy, for he compared the human skeleton with that of other Vertebrates.

Aristotle was quite well aware that each of the big groups of animals was built upon one plan of structure, which showed endless variations "in excess and defect" in the different members of the group. But he did not realise that this fact of community of plan constituted a problem in itself. His interest was turned towards the functional side of living things, form was for him a secondary result of function.

Yet he was not unaware of facts of form for which he could not quite find a place in his theory of organic form, facts of form which were not, at first sight at least, facts of function. Thus he was aware of certain facts of "correlation," which could not be explained off-hand as due to correlation of the functions of the parts. He knew, for instance, that all animals without front teeth in the upper jaw have cotyledons, while most that have front teeth on both jaws and no horns have no cotyledons .

Not only did he lay a foundation for comparative anatomy, but he made a real start with comparative embryology. Medical men before him had known many facts about human development; Aristotle seems to have been the first to study in any detail the development of the chick. He describes this as it appears to the naked eye, the position of the embryo on the yolk, the palpitating spot at the third day, the formation of the body and of the large sightless eyes, the veins on the yolk, the embryonic membranes, of which he distinguished two.

Aristotle had various systems of classifying animals. They could be classified, he thought, according to their structure, their manner of reproduction, their manner of life, their mode of locomotion, their food, and so on. Thus you might, in addition to structural classifications, divide animals into gregarious, solitary and social, or land animals into troglodytes, surface-dwellers, and burrowers .

The groups he distinguished were--man, viviparous quadrupeds, oviparous quadrupeds, birds, fishes, Cetacea, Cephalopoda, Malacostraca , Insecta , Testacea . A class of Acalephae, including sea-anemones and sponges, was grouped with the Testacea. The first five groups were classed together as sanguineous, the others as exsanguineous, from the presence or absence of red blood.

Besides these classes "there are," he says, "many other creatures in the sea which it is not possible to arrange in any class from their scarcity" .

Aristotle's greatest service to morphology is his clear recognition of the unity of plan holding throughout each of the great groups.

Speaking generally, the Sanguinea differ from man and from one another in their parts, which may be present or absent, or exhibit differences in "excess and defect," or in form. Unity of plan extends to all the principal systems of organs. "All sanguineous animals have either a bony or a spinous column. The remainder of the bones exist in some animals; but not in others, for if they have the limbs they have the bones belonging to them" . "Viviparous animals with blood and feet do not differ much in their bones, but rather by analogy, in hardness, softness, and size" . The venous system, too, is built upon the same general plan throughout the Sanguinea. "In all sanguineous animals, the nature and origin of the principal veins are the same, but the multitude of smaller veins is not alike in all, for neither are the parts of the same nature, nor do all possess the same parts" . It will be noticed in the first and last of these three quotations that Aristotle recognises the fact of correlation between systems of organs,--between limbs and bones, and between blood-vessels and the parts to which they go.

Sanguineous animals all possess certain organs--heart, liver, spleen, kidneys, and so on. Other organs occur in most of the classes--the oesophagus and the lungs. "The position which these parts occupy is the same in all animals " .

Unity of plan is observable not only in the Sanguinea, but also within each of the other large groups. Aristotle recognises that all his cuttlefish are alike in structure. Among his Malacostraca he compares point by point the external parts of the carabus , and the astacus , and he compares also the general internal anatomy of the various "genera" he distinguishes. As regards Testacea, he writes, "The nature of their internal structure is similar in all, especially in the turbinated animals, for they differ in size and in the relations of excess; the univalves and bivalves do not exhibit many differences" . There is an interesting remark about "the creature called carcinium" , that it "resembles both the Malacostraca and the Testacea, for this in its nature is similar to the animals that are like carabi, and it is born naked" . In the last phrase we may perhaps read the first recognition of the embryological criterion.

While Aristotle certainly recognised the existence of homologies, and even had a feeling for them, he did not clearly distinguish homology from analogy. He comes pretty near the distinction in the following passage. After explaining that in animals belonging to the same class the parts are the same, differing only in excess or defect, he says, "But some animals agree with each other in their parts neither in form nor in excess and defect, but have only an analogous likeness, such as a bone bears to a spine, a nail to a hoof, a hand to a crab's claw, the scale of a fish to the feather of a bird, for that which is a feather in the bird is a scale in the fish" . One of these comparisons is, however, a homology not an analogy, and the last phrase throws a little doubt upon the whole question, for it is not made clear whether it is position or function that determines what are equivalent organs.

His only excursion into the realm of "transcendental anatomy" is his comparison of a Cephalopod to a doubled-up Vertebrate whose legs have become adherent to its head, whose alimentary canal has doubled upon itself in such a way as to bring the anus near the mouth . It is clear, however, that Aristotle did not seek to establish by this comparison any true homologies of parts, but merely analogies, thus avoiding the error into which Meyranx and Laurencet fell more than two thousand years later in their paper communicated to the Acad?mie des Sciences, which formed the starting-point of the famous controversy between Cuvier and E. Geoffroy St Hilaire .

Moreover, Aristotle did not so much compare a Cephalopod with a doubled-up Vertebrate as contrast Cephalopods with all other animals. Other animals have their organs in a straight line; Cephalopods and Testacea alone show this peculiar doubling up of the body.

But there are other instances of correlation which seem to have taxed even Aristotle's ingenuity beyond its powers. Thus he knew that all animals with no front teeth in the upper jaw have cotyledons on their foetal membranes, and that most animals which have front teeth in both jaws and no horns have no cotyledons . He offers no explanation of this, but accepts it as a fact.

We may conveniently refer here to one or two other ideas of Aristotle regarding the causes of form. He makes the profound remark that the possible range of form of an organ is limited to some extent by its existing differentiation. Thus he explains the absence of external ears in birds and reptiles by the fact that their skin is hard and does not easily take on the form of an external ear . The fact of the inverse correlation is certain; the explanation is, though very vague, probably correct.

He who knows how to be happy and to win forgiveness for his happiness, how enviable he is!--the only true model among those that are wise.

It is now, just now, that these things ought to be said, in the hour when our old continent bleeds in every member, in the hour when our future seems blotted out by the menace of every sort of servitude and of a hopeless labor that will know neither measure nor redemption.

II POVERTY AND RICHES

The Christian doctrine, which has all the beauties, has all the audacities too. It has endeavored to make the sublime and daring notion prevail among the mass of men that salvation is reserved for the poor. What a magnificent thing! And if this religion of poverty has degenerated in the course of the centuries, with what consolation has it not bathed those thrice-happy souls whom an unbroken faith guides through misery and humiliation!

But there has never been a religion which has been able to found itself upon renunciation without compensation. Is he poor, this man who consents to go unclad, roofless, unfed, up to the day when there will be showered upon him all the riches of the kingdom of God? Has he no thought of a supreme gift, of a magnificent possession, the man to whom his master, in person, has given the command: "Lay up your treasures in heaven, where they will not be lost"?

He does not exist, the hopeless being who does not hunger for some treasure, even if it is an imaginary one, even an unreal one, even one that is lost in a bewildering future.

In what an abyss of poverty should we groan if our kingdom were not of this world and were nowhere outside the world, either?

And now a generation of men has come that no longer believes in the supernatural felicities of the future life and seems no longer to have anything to hope from a world consumed by hatred and given over inevitably, for long years, to confusion, destitution, egotistical passions.

In truth, the programmes of the social factions have no consolation for us, there is nothing in them that speaks of love and the true blessings; all these monuments of eloquence bring us back to hatred and anguish.

The most generous of them only give us glimpses of new struggles, new sheddings of blood, when our age is drunk with crime and fatigue. To whichever side the individual turns he finds himself crushed, scoffed at, sacrificed to insatiable, hostile gods.

A few years ago Maeterlinck wrote: "Up to the present men have left one religion to enter another; but when we abandon ours, it is not to go anywhere. That is a new phenomenon, with unknown consequences, in the midst of which we live."

Having quoted these words, I hasten to add that the war is no particular consequence of this moral state of the world. The question of religion is not involved at all. The priests are quite ready to abuse these easy oppositions in order to obtain arguments in favor of their cause. But they know well enough, alas! that if the teaching of Christ stigmatizes wars, the religions have only contributed to multiply and aggravate them. They know very well that, in the conflict that now divides the earth, the religions have shown themselves enslaved to the states. No one has wished to take up the wallet and staff of the dead Tolstoy.

Humanity seems poorer and more truly disinherited than ever. Its kingdom is in itself and in everything that surrounds it; but it has sold it for a morsel of bread. And how can one reproach it for this? It is very hungry and its heart is not open to beauty.

We shall seek together the materials of our happiness. Together we shall pile up all those marvelous little things that must constitute our patrimony, our wealth.

We shall have great misfortunes and we shall often be bitterly deceived. It is because the war has succeeded in depriving the simplest and the most sacred things of the light of eternity. That is not the least consequence of the catastrophe. We must make a painful effort to recover that light and clear it of its blemishes. Silence, solitude, the sky, the vestiture of the earth, all the riches of the poor have been sullied as if forever. The works of art have been mutilated. They have taken refuge under the earth where they seem to veil their faces.

We ought to seek and gather together the debris so that we can take up and love in secret every day the fragments of our liberties.

We ought to think unceasingly of that "mean landscape" of which Charles Vildrac has spoken in one of his most beautiful poems. It is an unfruitful landscape, despoiled, denatured by the sad labor of men, and apparently worn out;--

But even so you found, if you sought there, One happy spot where the grass grew rich, Even so you heard, if you listened, The whisper of leaves And the birds pursuing one another.

And if you had enough love, You could even ask of the wind Perfumes and music ...

We shall have enough love! That shall be the principle and source of our wealth.

And so we shall not have a whole life of poverty. When love, that is to say, grace, abandons us, we shall perhaps know hours of poverty. That will help us all the better to understand our hours of opulence, and all the better cherish them.

If you wish, we can divide our task, enumerate the coffers in which we are to pile our treasures.

First of all, let us stop over a word. We have said: to possess is to know. The definition may seem to you arbitrary. On the chance of this I open my little pocket dictionary, which is the whole library I have as a soldier, and read: "To possess: to have for oneself, in one's power, to know to the bottom." Let us accept that. We shall see, page by page, if it is possible for us to satisfy these na?ve, direct definitions.

What is most certain to attract our glance, when we look about us, is the world of men, our fellow-creatures. Their figures are certainly the most affecting spectacle that can be offered us. Their acts undoubtedly constitute, owing to a natural inclination and an indestructible solidarity, the chief object of our curiosity. Good! We shall possess them first of all. We shall possess this inexhaustible fund of other people.

We shall feel no shame then in contemplating, with a noble desire, whatever strikes our senses, the animals, that is to say, the plants, the material universe of stones and waters, the sky and even the populous stars. These, too, ought to be well worth possessing!

Share on: WhatsApp @Hash Facebook Tweet