The Nature of Man: Studies in Optimistic Philosophy

As this part of the body in monkeys, on the contrary, is much more hairy than the under surface, it has been held to constitute an essential difference between man and monkeys. But embryological study enables us to settle this apparent contradiction. The foetus of the gorilla exa- mined by M. Deniker possessed an almost entirely smooth back. " The foetus had true hairs only on the head, the anterior surface, and around the lips and the genital organs, and the eyelashes and eyebrows. The remainder of the body was smooth or covered with down not exceeding a millimetre in length." *

The skin of the under surface, smooth around the navel, was covered with small hairs more thickly than on the back. The abundance of hairs on the posterior aspect of the body of monkeys is a later acquisition, which develops but tardily during foetal life. As regards the distribution of these hairs man resembles much more the embryos of monkeys than adult monkeys. This fact, instead of shaking the theory of relationship between man and apes, gives us strong evidence as to the mode of his descent. Putting the known facts together, we may infer that man is a case of the arrested develop- ment of some simian of ancient days, as it were, a simian monster from the zoological point of view, although not from the aesthetic. Man may be regarded as a prodigy sprung from an ape, born with a larger brain and an intel- ligence more highly developed than occurred in his parents. Such a view is in accordance with known facts.

It must be admitted that certain kinds of organisms, instead of evolving at a very slow pace, spring up suddenly, and that in such a case nature proceeds with a considerable stride. Darwin foresaw this possibility, but it has been made plain to us by the remarkable researches of the botanist Hugo de Vries.* De Vries cultivated for fifteen years the Evening Prim- rose, a plant of American origin ((Enotera lamarckiana). He obtained, suddenly, a set of flowers quite distinct from those of the original plant. They presented such great differences that, he could separate them a-, several quite distinct species. During the first few years ^e Vries obtained three species ((Enotera lata, CEn. nanella, and sometimes (En. scintillans), but variation becoming more and more prevalent, he ultimately distinguished a dozen new species. These were grown from seed, and transmitted their specific characters to their descendants. De Vries, in this way, was a witness of the sudden appearance of new species.

It is probable that man owes his origin to a similar pheno- menon. Some anthropoid ape having at a certain period become varied in specific characters, produced offspring endowed with new properties. The brain, of abnormal size, placed in a spacious cranium, allowed a rapid develop- ment of intellectual faculties much more advanced than those of the parent and those of the original species. This peculiarity would be transmitted to the descendants, and, as it was of very considerable advantage in the struggle for existence, the new race would hold its own, propagate and prevail. The extraordinary development of intelli- gence necessarily led to perfections in the choice of nour- ishment, perfections which approached the art of preparing more digestible food. The jaws, under these conditions, had not such a difficult task as before, and, moreover, they were no longer required for attack or defence. They became less developed than in the true anthropoid apes. * " Die Mutations theorie," vol. I., Leipzig, 1901.

These suggestions involve a conception of the mind that is in harmony with known facts. From time to time pro- digies are born with some talent far greater than the gifts possessed by the parents. About twelve years ago a young native of Piedmont, Jacques Inaudi by name, became famous in Paris on account of his extraordinary power of calculation. He had an astonisi.'ng memory for figures, and could perform mathe- matical calculations with surprising rapidity.* Two minutes were sufficient for him to multiply two numbers composed of seven and six figures. Other arithmetical calculations, such as the extraction of roots, gave him but little trouble.

To attain this result, Inaudi made use of his extraordinary memory for figures, founded on the persistence of auditory images. When he heard the numbers pronounced, he remembered them. Inaudi declared to the Commission convened by the Academy of Sciences, that when he tried to recall the numbers he heard them as if repeated aloud, in the tone of his own voice, and that he could hear them for the greater part of the day. "In an hour, or in two hours' time, if I thought of the number that was uttered, I should be able to repeat it as exactly as I have done before the Commission."

Now this very extraordinary and rare auditory memory was developed in an altogether abrupt way. Inaudi, the son of poor peasants of Piedmont, passed the first years of his life as a shepherd. At the age of six his wonderful faculty of calculating figures appeared. He did not know at this time how to read or to write. At eleven years of age he astonished the members of the Anthropological Society of Paris by his phenomenal memory, and it was only much later, at the age of twenty, that he learnt to read and write. Neither of the parents of Inaudi had shown in the slightest degree a calculating faculty like that of little Jacques. It must then be admitted that it was developed as suddenly as the new qualities in the Evening Primrose that we have already mentioned.

The first men, also, were probably ingenious children, born of anthropoid parents. This hypothesis very well explains the fact that man is more like the foetus and the young of anthropoid apes than the adult animals, and exhibits only a trace of many organs which are much more developed in simian species. A very distinguished German anatomist, Wiedersheim,* has given in a pamphlet a resumg of our actual knowledge of the organs of man from the point of view of their descent. He has found fifteen organs which show in the human species a considerable advance on those of anthropoid apes. The chief of these are the lower limb, well adapted for a constant erect carriage of the body ; the strengthening of the pelvis and of the sacrum, as well as the broadening of the more slender pelvis of the female ; the curvature of the lumbar part of the vertebral column ; the development of the buttocks and of the calves ; the difference of certain muscles of the face ; the nose ; certain strands from the brain to the spinal cord ; the occipital lobe of the brain ; the greater development of the cerebral cortex, and, lastly } the considerable differentiation of the muscles of the larvnx which permit speech.

But besides these progressive organs, Wiedersheim has counted seventeen decaying organs, still able to fulfil their physiological function in a more or less incomplete * "Dei Bau des Menschen," Third Edition, 1902, manner (amongst these are the decadent muscles of the leg and foot ; the eleventh and twelfth pairs of ribs, the toes, the caecum, etc.), and not less than one hundred and seven rudimentary organs which serve no useful physio- logical purpose (to this category belong the coccyx — the vestige of a tail — the thirteenth pair of ribs in the adult, the muscles of the ear, the vermiform appendage, etc.).

We have already shown in the preceding chapter the great importance of rudimentary organs as aids to the tracing of the genealogy of organisms. These organs, use- less at present, are the vestiges of similar but more developed organs, which fulfilled a useful function in our ancestors. The extraordinary quantity of rudimentary organs in man furnishes another proof of his animal origin, and puts at the disposal of science information of great value for the philosophic conception of human nature.

Perfection of the human form — The covering of hair — The dentition in general and the wisdom teeth — The vermiform appendage — Appendicitis and its gravity — Uselessness of the caecum and of the large intestine — Instance of a woman without a large intestine — Ancestral history of this portion of the digestive tract — Injurious effect of the microbes of the large intestine — Frequency of cancer of the large intestine and of the stomach — Limited usefulness of the stomach — The instinct of choice of food — Futility of this instinct in man

ALTHOUGH he is a recent arrival on the earth, man has made great progress as compared with his ancestors, the anthro- poid apes. A comparison between even the lower races of man, such as the Hottentots or the aborigines of Aus- tralia and higher types such as the inhabitants of Europe and of North Africa, shows that a very great advance has been made. Human art has been able to surpass nature in many instances. No natural sound is so perfect as some of the more beautiful pieces of modern music. Even in the pro- duction of form, man has triumphed over nature. Breeders of flowers or of birds seek to produce new varieties. With this object they often frame a conception of what they desire to produce, and, so to speak, set about to realise their pro- gramme. They prepare ideal images to serve t.hem as

guides in the process of production. By the method of artificial selection they often succeed in their wishes, and add to their collections some remarkable form. In such fashions aviculture and horticulture have produced birds and flowers more beautiful than any found in nature. In regard to the human body, attempts have been made to surpass nature and to represent a body corresponding to an artistic ideal. To arrive at something more beautiful than man, the wings of birds or the characters of some other creatures have been added to his presentment. Such attempts have had no other result than to show that the human form, as created by nature, cannot be surpassed. The ancient conception of the human body as the artistic ideal has been fully justified. The views of those religious fanatics who have thrown contempt on the body by repre- senting it in degraded forms, must be rejected.

It is impossible, however, to apply this result to our con- ception of the nature of man in general. The beautiful form of the human body appears only in youth and in maturity. In old age, the bodies of men and women are generally ugly, and in extreme old age it is almost impossible to see the traces of former beauty. Nor can conceptions of perfection drawn from the human face and body be extended to the whole of man's organisa- tion. A glance at some of the organic systems will make this plain.

The human skin is covered with little hairs, the history of which is interesting. In one stage of embryonic life nearly the whole of the body is clad with hairs. This covering is known as the lanugo, and consists of strands of hair, dis- posed very regularly all over the body, save on the nose and the hands and- feet. There is no doubt but that this is functionless, and is no more than an inheritance from the old ape-like condition. Later on, it falls out and is replaced by the ordinary downy covering of the body. In adult life, and particularly in old age, the hairs of the second coat tend to grow very long and so to form a covering that is neither beautiful nor in the least degree useful. We may take this as a first example of a disharmonious condition in the human body. Hairs, incapable of protecting the body from cold, survive merely as an ancestral relic and may become even harmful.

The human skin is constantly exposed to the microbes in dust ; and the follicles of the hairs, in which these microbes lodge, form receptacles very favourable to their multipli- cation. In the hollows of the follicles, certain microbes, as for instance some of the Staphylococci, multiply rapidly and give rise to acne and to pimples. The process may even go the length of producing a chronic skin-disease very unpleasant and even dangerous if it be associated with suppuration.

In the human race, intelligence, that is to say, the activity of the brain, supplants many other functions, and man is able to protect himself against the inclemencies of weather much better than his furry ancestors were capable of doing. He is able to do this through his invention of clothing which may be varied with the nature of the weather. But the obstinate laws of inheritance burden him with a covering of hair, not only useless but frequently harmful. And this is only one example among many.

Although, in an extreme case, man is able to survive the total loss of the teeth, it cannot yet be said that teeth are useless or harmful. None the less, a study of the human dentition reveals that this set of organs is out of harmony with the fundamental needs of our race. The monkeys of the old world (Catarrhines), although they belong obviously to the brute creation, already exhibit a tendency to reduction in the number of teeth. While American monkeys (Platyrrhines) may possess thirty-six teeth, the old world forms do not possess more than thirty-two in all, at least as a normal occurrence. Selenka * has shown that among gorillas and ourangs individuals with a fourth pair of molars, bringing up the number of teeth to thirty-six, are not rare, He found these additional molars in 20 per cent, of one hundred and ninety-four adult skulls of ourangs. On the other hand, in the cases of the chimpanzee and the gibbon, the third pair of molars differ from the others in smaller size and occasional absence. This reduction is to be asso- ciated with the smaller jaws and less powerful mastication of these anthropoids.

Cases of supplementary molars are very rare in man, and occur more frequently in the lower races, such as negroes, Australians, and natives of New Caledonia. f On the other hand, absence of the third pair of molars, that is to say, of the wisdom teeth, is quite frequent, especially in the white races. Nearly 10 per cent, of Europeans throughout their lives have no more than twenty-eight teeth, the wisdom teeth being absent. This absence is more common in the upper jaw, where it occurs in from 18 to 19 per cent, of men. The loss of the wisdom teeth J is on the whole to be regarded as an advantage. Certainly from the '" physio- logical point of view the part played by the wisdom teeth is subordinate. Their power of masticating is feeble ; the loss does not appreciably interfere with mastication. The complete absence of all four has no influence on mastica-

tion." * These teeth are cut very late, often not appearing until the thirtieth year and sometimes being delayed to extreme old age. Even if they were only useless, the wisdom teeth would furnish an instance of disharmony in the human body. But these teeth often are a source of trouble which, although it is not often serious, may lead to grave diseases and even to death. No other teeth are so subject to accident. This is due partly to the slowness with which they develop and to the difficulty they encounter in cutting the mucous membrane. Dental caries, moreover, is specially frequent in them.f The membrane surrounding them is specially subject to small lesions by which the infection spreads to adjacent parts. Inflammatory conditions frequently arise from these teeth, and tumours, caries of the jaw-bone and even diffused suppuration, leading to death, may be sequelae of wounds of the wisdom teeth. Galippe J has described a case in which one of these teeth, failing to cut the gum in the normal position, made its way through the cheek. This produced an inflammatory suppuration of the cheek with numerous nstulee and an inflammation of the masseter muscle which made it impossible for the mouth to open. Notwithstanding the extraction of the wisdom tooth that had been the cause of all these troubles, the patient died of meningitis, which had started from the tooth. Other cases have been described in which a difficult eruption of the tooth led to formation of an abscess in the bone, from which there arose a fatal abscess of the brain.

tumours. Magitot * writes that very many neoplasms of the jaw may be traced to a source of origin in the socket of the wisdom tooth. There is no useful function of these teeth to set against their disadvantages. It was our remote ancestors, masti- cating hard food, that had the advantages of these additional teeth. In man they are rudimentary organs, and provide another proof of our simian origin. The cjEcal or vermiform appendage is another rudimentary organ in the human body, and is interesting from many points of view. I have already referred to its importance as definite evidence of our origin from lower animals, and shown how striking is the resemblance of the human organ to that of the anthropoid apes. It consists of a thick wall, containing glands, a muscular layer and lymphoid clumps. That it performs no function useful to man is made clear by the existence of undisturbed health in persons from whom it has been removed. Thanks to the advances of modern surgery, this organ has been removed very often, and some- times even in cases where it did not appear to have been diseased. In a great majority of the cases, the removal of the organ succeeded well, and the patients experienced no harm, but appeared to carry on all the processes of digestion with equal completeness.

On the other hand, the caecal appendage in man is fre- quently obliterated, there being no trace of the normal aperture, so that there is no connection between it and the general digestive cavity. According to Ribbert,| nearly one person in four possesses the appendage in an obliterated condition, the condition being particularly frequent in the aged. In young persons and infants the aperture of the appendage is usually open. In cases where there is no com- munication with the cavity of the digestive tract, the pro- cesses of digestion appear to be normal. It is logical to conclude that in the human being the function of the caecum is either absent or very slight.

Even in the anthropoid apes the appendage of the caecum appears to be a rudimentary structure, with a function at most accessory to that of the lymphoid clumps. In lower old-world monkeys the vermiform appendage does not usually exist, cases such as that of Cercopithecus sabaeiis, in which it is present as a little boss, being rare. It is necessary to seek the purpose of this structure still lower in the scale of life. In some herbivorous creatures the caecum is large, and ends in a portion richly provided with lymphoid tissue, and similar to the vermiform appendage. The rabbit and certain marsupials are good examples. Undoubtedly, in their cases, the portion of the digestive canal which corre- sponds to the vermiform appendage of man is active in the digestion of vegetable matter. The organ is a very old part of the constitution of mammals, and it is because it has been preserved long after its function has disappeared that we find it occurring in the body of man.

Rudimentary organs for the most part display a con- genital lack of the power of resistance, and, as Darwin suggested, for this reason they are frequently the seats of disease. When Darwin wrote his work on the " Descent of Man," more than a quarter of a century ago, many fatal cases of inflammation of the appendage had not been recorded. Darwin quoted only two cases as known to him. Since then, appendicitis (the name given by American surgeons to the first acute or to the chronic inflammation of the appendage) has become a well-known disease in Europe and

America, and occupies considerable space in treatises on the pathology of the digestive tract. To give an idea of the prevalence of appendicitis, 1 may mention that in a single Paris hospital (Hopital Trousseau) four hundred and forty-three cases of the disease have been treated in the five years 1895-1899.* In many of these cases the subjects were infants, as these as a rule are much more subject to appendicitis than are the aged. According to Treves,f the well-known English surgeon, 36 per cent, of the observed cases were under twenty years of age. Among old men, on the other hand, appendicitis is a rare exception. The varying incidence of the disease at different ages no doubt depends on the fact that in old age the appendage is often obliterated. The more easy communication with the other portion of the gut may be, the more chance there is for inflammation to occur. As it has a muscular layer, the appendage is able to void its fcecal contents ; and a Scotch surgeon, Parker Syms, J has seen an appendage that he had removed, in the act of writhing about like an earth- worm. Such movements, undoubtedly, would aid the dis- charge of the contents of the cavity.

The movements of the appendage, however, are usually feeble, and thus stagnation of the contents is common. Foreign matter is often found in the cavity, such as the pips of fruit, seeds, hairs, thorns, and in rare cases pins or even tin-tacks. Such bodies are capable of wounding the inner wall of the appendage, and so giving an opportunity to the microbes that abound in the digestive tube, with the result that microbial infection and inflammation of the

* Lannelongue, in the "Bulletin medical," p. 621, 1902. f Treves, " The Surgical Treatment of Perityphlitis," London J Edinburgh Medical Journal, August 1893, organ is produced. Often, too, intestinal worms pass into the appendage arid become the carriers of pathogenic organisms. Appendicitis is usually a grave disease, and is fatal in from 8 to 10 per cent, of cases. It would be difficult to find anywhere else in the human body so flagrant a case of natural disharmony. The organ in question may be obliterated or removed without disturbance of function, and, moreover, in its normal condition is a frequent cause of serious illness !

The vermiform appendage is not the only part of the digestive canal that is out of harmony with the mainten- ance of life and health. The caecum itself, of which the appendage is only a portion, is degenerating in the human body, as I stated in the last chapter. The human caecum, in fact, is very little developed in comparison with the caecum of most herbivorous animals, in which it is a true organ of digestion. In the human embryo the caecum and the appendage are relatively better developed than they are in the adult.

Disharmony is exhibited in the human body not only by rudimentary organs such as the wisdom teeth and the appendage, or by degenerating organs such as the caecum. Some very large parts of our alimentary canal must be regarded as useless inheritances, bequeathed to us by our animal ancestors. It is no longer rash to say that not only the rudimentary appendage and the caecum but the whole of the large intestine are superfluous, and that their removal would be attended with happy results. So far as digestion goes, the latter portion of the alimentary tract is of little importance. Even from the point of view of absorp- tion of the products of digestion its importance is strictly secondary. And so it is not astonishing to find that the

removal or disappearance of nearly the whole of the large intestine can be supported well by man. As one result of the astonishing progress of surgery, it has been found possible to excise certain parts of the gut, and particularly of the large intestine. Thus, in one case, Korte * removed, along with part of the small intestine, a considerable part of the large intestine, leaving in place only the terminal portion. The patient, who underwent eight successive abdominal operations, recovered. In the case f of another patient, operated on by Wiesinger, two coils of the large intestine (the transverse and descending colons) which were ulcerated, were isolated from the re- mainder of the gut, while the upper portion of the large intestine (the caecum and the ascending colon) was sutured to the rectum. In spite of these serious interferences with natural structure, the patients recovered, and appeared to derive great advantage from the loss of the large intestine.