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The chapters on Inheritance, and on Reversion to ancestral characters, or atavism, are profoundly suggestive. What can be more wonderful, the author asks, than that some trifling peculiarity should be transmitted through a long course of development, and ultimately reappear in the offspring when mature or even when old? Nevertheless, the real subject of surprise is not that a character should be inherited, but that any should ever fail to be inherited. Gradually leading up to the important hypothesis with which the work closes, he observes that to adequately explain the numerous characters that reappear after intervals of one or more generations, we must believe that a vast number of characters, capable of evolution, lie hidden in every organic being. “The fertilised germ of one of the higher animals, subjected as it is to so vast a series of changes from the germinal cell to old age – incessantly agitated by what Quatrefages well calls the tourbillon vital– is perhaps the most wonderful object in nature. It is probable that hardly a change of any kind affects either parent, without some mark being left on the germ. But on the doctrine of reversion the germ becomes a far more marvellous object, for, besides the visible changes to which it is subjected, we must believe that it is crowded with invisible characters, proper to both sexes, to both the right and left side of the body, and to a long line of male and female ancestors separated by hundreds or even thousands of generations from the present time; and these characters, like those written on paper with invisible ink, all lie ready to be evolved under certain known or unknown conditions.”

Through a further discussion of many deeply interesting facts, about the intercrossing of breeds and species, and about the causes of variability, we pass to the hypothesis of pangenesis, which, briefly stated, supposes that the cells or units of the body are perpetually throwing off minute granules or gemmules, which accumulate in the reproductive system, and may, instead of developing in the next generation, be transmitted in a dormant state through more than one generation and then be developed. Combination in various degrees between these gemmules is supposed to influence their appearance or non-appearance in the offspring at various stages.

This hypothesis certainly gives a picture of a possible mode of accounting for many peculiarities shown by living organisms. Although not generally accepted, it has certainly not been disproved. Mr. Grant Allen’s opinion that it is Darwin’s “one conspicuous failure,” and that it is “crude and essentially unphilosophic,” must be discounted by his known devotion to Mr. Herbert Spencer’s philosophy. If Darwin had been a specialist in modern physiology, he might, perhaps, have expressed his hypothesis in a more persuasive form; but Weismann’s germ plasma theory is the only alternative one hitherto suggested in place of it.

CHAPTER VII

ALTHOUGH the descent of man from animal ancestors was directly implied in the “Origin of Species,” Darwin hesitated at the time of its publication to declare his views fully, believing that he would only thus augment and concentrate the prejudice with which his theory would be met. He had for many years held the views he afterwards expressed; but it was not until he had by his other works raised up a strong body of scientific opinion in favour of his great generalisation, that he fully presented his views on man to the public. The “Descent of Man” was studied as a special case of the application of his general principles, a test all the more severe because several classes of argument were necessarily cut off, such as the nature of the affinities which connect together whole groups of organisms, their geographical distribution, and their geological succession. But adopting the high antiquity of man as demonstrated, he considered in detail the evidence as to man’s descent from some pre-existing form, the manner of his development, and the value of the differences between the so-called races of man. No originality is claimed for the theory or for the facts advanced; but it may safely be affirmed that the master’s acuteness, his moderation, his candour, and his desire to state facts which tell against him, are as conspicuous in the “Descent of Man” as in any of his works.

The “Descent of Man,” which was published in 1871 in two volumes, with numerous illustrations, began, after a short introduction, with a suggestive series of questions, which to the evolutionist suffice to decide the question as to man’s origin. As the answers to these questions are obvious, Darwin first concentrated his inquiry upon two points on which disputes must necessarily occur, namely, the traces which man shows, in his bodily structure, of descent from some lower form, and the mental powers of man as compared with those of lower animals. The facts of our bodily structure are inexplicable on any other view than our community of descent with the quadrumana, unless structure is but a snare to delude our reason. It is only our natural prejudice, says Darwin, and that arrogance which made our fathers declare that they were descended from demigods, which leads us to demur to this conclusion.

The comparison of the mental powers of animals with those of man, proving, as Darwin contends, that they therein also show traces of community of descent, was certain to provoke much more debate, for the term “instinct” and the use made of it by naturalists and psychologists as signifying untaught, unlearnt ability, largely tended to obscure the question, and to create prejudices against believing that instincts could be built up by inherited experience, that instincts were really not absolute and fixed, but relative and variable, and that all instincts were not perfect or perfectly useful. The working out of the evolution theory as applied to animal minds, the study of the first beginnings of nerve action, and the analysis of instinct, all due largely to Darwin’s prominent disciple, Romanes, together with the immensely fuller knowledge of molecular physics, of protoplasm, and of brain function, acquired in the years since Darwin wrote, have sufficed to place these questions on a much more secure basis. But the collection of facts made by him, and the suggestive remarks he everywhere makes, render his book of permanent value. His sympathy is obvious in such passages as this: “Every one has heard of the dog suffering under vivisection who licked the hand of the operator; this man, unless he had a heart of stone, must have felt remorse to the last hour of his life;” the “terrible” superstitions of the past, such as human sacrifices, trial by ordeal, &c., show us, he says, “what an indefinite debt of gratitude we owe to the improvement of our reason, to science, and our accumulated knowledge.” We see the fruit of Darwin’s repeated visits to the Zoological Gardens, especially in his study of the habits and mental powers of monkeys. We gain a definition from him of imagination, by which faculty man “unites, independently of the will, former images and ideas, and thus creates brilliant and novel results… The value of the products of our imagination depends of course on the number, accuracy, and clearness of our impressions; on our judgment and taste in selecting or rejecting the involuntary combinations, and to a certain extent on our power of voluntarily combining them.” As to religion, he says, “There is no evidence that man was aboriginally endowed with the ennobling belief in the existence of an omnipotent God.” On the contrary, evidence proves that there are and have been numerous races without gods and without words to express the idea. The question, he says, is “wholly distinct from that higher one, whether there exists a Creator and Ruler of the universe; and this has been answered in the affirmative by the highest intellects that have ever lived.” The fact of races existing without a belief in a god is shown to be compatible with the origin of religious ideas from attempts to explain external phenomena and man’s own existence, by attributing to other objects and agencies a similar spirit to that which his consciousness testifies to in himself.

Man’s social qualities, as well as those of animals, Darwin regards as having been developed for the general good of the community, which he defines as “the means by which the greatest possible number of individuals can be reared in full vigour and health, with all their faculties perfect, under the conditions to which they are exposed.” This may be regarded as a more satisfactory expression of the idea underlying the phrase, “the greatest happiness of the greatest number.” Sympathy for animals he notes as one of the later acquisitions of mankind, and remarks that he found the very idea of humanity a novelty to the Gauchos of the Pampas. “The highest stage in moral culture at which we can arrive is when we recognise that we ought to control our thoughts… Whatever makes any bad action familiar to the mind, renders its performance so much the easier” – a significant expression for those who would compare the teachings of Darwinism with those of Christianity. Finally, he concludes that the difference in mind between man and the higher animals is one of degree, not of kind. “At what age does the new-born infant possess the power of abstraction, or become self-conscious and reflect on its own existence? We cannot answer; nor can we answer in regard to the ascending organic scale.” Yet that man’s mental and moral faculties may have been gradually evolved “ought not to be denied, when we daily see their development in every infant; and when we may trace a perfect gradation from the mind of an utter idiot, lower than that of the lowest animal, to the mind of a Newton.”

The action of natural selection on the variations known to occur in man, is next shown to be sufficient to account for his rise from a lowly condition. Perhaps it is in discussing the development of the intellectual and moral faculties that Darwin is least successful; more knowledge of psychology than he possessed is demanded for this discussion. He gives up the problem of the first advance of savages towards civilisation as “at present much too difficult to be solved.” He, however, vigorously contests the idea that man was at first civilised and afterwards degenerated; and expresses the opinion that the “highest form of religion – the grand idea of God hating sin and loving righteousness – was unknown during primeval times.” Finally, after discussing the steps in the genealogy of man, he comes to the conclusion that from the old-world monkeys, at a remote period, proceeded man, “the wonder and glory of the universe.” The early progenitors of man he believes to have been covered with hair, both sexes having had beards; their ears were pointed and capable of movement; their bodies were provided with a tail, and the foot was probably prehensile. Our primitive ancestors lived chiefly in trees in some warm forest-clad land, and the males were provided with formidable weapons in the shape of great canine teeth.

“Thus,” says Darwin, “we have given to man a pedigree of prodigious length, but not, it may be said, of noble quality. The world, it has been often remarked, appears as if it had long been preparing for the advent of man; and this, in one sense, is strictly true, for he owes his birth to a long line of progenitors. If any single link in this chain had never existed, man would not have been exactly what he now is. Unless we wilfully close our eyes, we may, with our present knowledge, approximately recognize our parentage; nor need we feel ashamed of it. The most humble organism is something much higher than the inorganic dust under our feet; and no one with an unbiassed mind can study any living creature, however humble, without being struck with enthusiasm at its marvellous structure and properties.”

In considering the formation and perpetuation of the races of mankind, Darwin was again and again baffled. He could not decide that any of the physical differences between the races are of direct and special service to him, thus giving opportunity to natural selection to work. Hence he was led to study in detail the effects of sexual selection, especially as applicable to man. The greater part of “The Descent of Man” is occupied with tracing out what may be called the history of courtship in man and animals. The great variety of interesting subjects dealt with cannot be detailed here. We must only notice a few points about mankind which are of special importance.

Darwin concludes that man’s predominance over woman in size, strength, courage, pugnacity, and even energy was acquired in primeval times, and that these advantages have been subsequently augmented chiefly through the contests between men for women. Even man’s intellectual vigour and inventiveness are probably due to natural selection, combined with inherited effects of habit, for the most able men will have succeeded best in defending and providing for their wives and offspring. Beards, beardlessness, voice, beauty are all related to sexual charm, and have been selectively developed. Early man, less licentious, not practising infanticide, was in several respects better calculated to carry out sexual selection than he is now; and thus we find the various races of men fully differentiated at the earliest date of historic records.

Incidentally Darwin gives us his views on the mental differences between man and woman. Woman is more tender and less selfish than man, whose ambition “passes too easily into selfishness,” which latter qualities “seem to be his natural and unfortunate birthright.” Woman’s powers of intuition, of rapid perception, and perhaps of imitation, are more strongly marked than in man. Yet the chief pre-eminence of man he considers to consist in attaining greater success in any given line than woman, by reason of greater energy, patience, &c. “In order that woman should reach the same standard as man, she ought, when nearly adult, to be trained to energy and perseverance, and to have her reason and imagination exercised to the highest point, and then she would probably transmit these qualities chiefly to her adult daughters.” Here we have a plan of women’s higher education according to the great evolutionist, although he does not assert that it is the essential and desirable one; but given a certain object, here is the best method of securing it. “The whole body of women, however, could not be thus raised, unless during many generations the women who excelled in the above robust virtues were married, and produced offspring in larger numbers than other women.”

The doctrine that man is descended from some less highly organised form, Darwin asserts in his concluding chapter, rests on grounds which will never be shaken – namely, the similar structure and course of development of embryos of the higher animals, and vast numbers of facts of structure and constitution, rudimental structures, and abnormal reversions. The mental powers of the higher animals graduate into those of man. Language, and the use of tools, made man dominant. The brain then immensely developed, and morality sprang from the social instinct. Comparing and approving certain actions and disapproving others, remembering and looking back, he became conscientious and imaginative. Sympathy, arising in the desire to give aid to one’s fellows, was strengthened by praise and blame, and conduces to happiness. “As happiness is an essential part of the general good, the greatest happiness principle indirectly serves as a nearly safe standard of right and wrong… But with the less civilised nations reason often errs, and many bad customs and base superstitions come within the same scope, and consequently are esteemed as high virtues and their breach as heavy crimes.”

The belief in God, the author says, is not innate or intuitive in man, but only arises after long culture. As to the bearing of the evolution theory on the immortality of the soul, Darwin thinks few people will find cause for anxiety in the impossibility of determining at what period in the ascending scale man became an immortal being. “The birth, both of the species and of the individual, are equally parts of that grand sequence of events, which our minds refuse to accept as the result of blind chance. The understanding revolts at such a conclusion.”

The bearing of the Darwinian doctrine on some important practical questions for society leads to the remark that, while man scans with scrupulous care the pedigree of his animals, when he comes to his own marriage he rarely or never takes any such care. Perhaps Darwin was somewhat in error here; and, also, he seems to have underrated the unconscious tendency to act according to natural law, which has no doubt influenced mankind largely. He lays down the principle that both sexes ought to refrain from marriage if markedly inferior in body or mind, or if they cannot avoid abject poverty for their children. When the laws of inheritance are thoroughly known, he says, we shall not hear ignorant members of our legislature rejecting with scorn a plan for ascertaining, by an easy method, whether or not consanguineous marriages are injurious to man. But Darwin is by no means in favour of any restriction on man’s natural rate of increase; for it is the greatest means of preventing indolence from causing the race to become stagnant or to degenerate. Only, there should be open competition for all men; and the most able should not be prevented by laws or customs from succeeding best and rearing the largest number of offspring.

In summing up on the entire subject, Darwin expresses himself with more than his wonted vigour and point. On the one hand, he endeavours to disarm opposition by quoting heroic monkeys as contrasted with degraded barbarians; on the other hand, he welcomes the elevation of man so far above his barbarous ancestors. Finally, he takes his stand upon truth, as against likes and dislikes. “The astonishment which I felt on first seeing a party of Fuegians on a wild and broken shore will never be forgotten by me, for the reflection at once rushed into my mind – such were our ancestors. These men were absolutely naked and bedaubed with paint; their long hair was tangled, their mouths frothed with excitement, and their expression was wild, startled, and distrustful. They possessed hardly any arts, and, like wild animals, lived on what they could catch. They had no government, and were merciless to every one not of their own small tribe. He who has seen a savage in his native land will not feel much shame, if forced to acknowledge that the blood of some more humble creature flows in his veins. For my own part, I would as soon be descended from that heroic little monkey, who braved his dreaded enemy in order to save the life of his keeper; or from that old baboon, who, descending from the mountains, carried away in triumph his young comrade from a crowd of astonished dogs – as from a savage who delights to torture his enemies, offers up bloody sacrifices, practises infanticide without remorse, treats his wives like slaves, knows no decency, and is haunted by the grossest superstitions.

“Man may be excused for feeling some pride at having risen, though not through his own exertions, to the very summit of the organic scale; and the fact of his having thus risen, instead of having been aboriginally placed there, may give him hopes for a still higher destiny in the distant future. But we are not here concerned with hopes or fears, only with the truth as far as our reason allows us to discover it. I have given the evidence to the best of my ability; and we must acknowledge, as it seems to me, that man, with all his noble qualities, with sympathy which feels for the most debased, with benevolence which extends not only to other men, but to the humblest living creature, with his god-like intellect which has penetrated into the movements and constitution of the solar system – with all these exalted powers – Man still bears in his bodily frame the indelible stamp of his lowly origin.”

The reception accorded to “The Descent of Man” was more excited than that of “The Origin of Species.” The first large edition was quickly exhausted, and discussion or ridicule of the book was the fashionable recreation. Mr. Punch, week after week, reflected passing opinion. One of his Darwinian ballads on our ancestors is worth quoting from: —

 
  “They slept in a wood,
Or wherever they could,
For they didn’t know how to make beds;
They hadn’t got huts,
They dined upon nuts,
Which they cracked upon each other’s heads.
They hadn’t much scope
For a comb, brush, or soap,
Or towels, or kettle, or fire;
They had no coats nor capes,
For ne’er did these apes
Invent what they didn’t require.
 

·····

 
From these though descended,
Our manners are mended,
Though still we can grin and backbite;
We cut up each other,
Be he friend or brother,
And tails are the fashion – at night.
This origination
Is all speculation —
We gamble in various shapes;
So Mr. Darwin
May speculate in
Our ancestors having been apes.”
 

The Athenæum was unbelieving, but not denunciatory. The Edinburgh Review declared the doctrine of natural selection hopelessly inadequate to explain the phenomena of man’s body; although its truth and falsehood had no necessary connection with the general theory of evolution: some law as yet unknown being looked for. Darwin’s attempt to explain the evolution of mind and the moral sense is regarded as failing in every point. “Never, perhaps, in the history of philosophy, have such wide generalisations been derived from such a small basis of fact.” The Quarterly Review now acknowledged that “the survival of the fittest” was a truth which readily presented itself to any one considering the subject, and that to Darwin was due the credit of having first brought it forward and demonstrated its truth, and asserted that the destruction of the least fit was recognised thousands of years ago. But, in regard to the descent of man, it fastens specially upon the author’s theory of mental and moral evolution, and declares that he has utterly failed. The Saturday Review, however, admitted the high antiquity of man, and the nearness of his bodily structure to the apes, and went much further. In discussing the evolution of morals, the author’s unexampled grasp of facts, with his power of correlation, is, according to The Saturday, seen at its highest, in an exquisite chain of philosophical deduction. The mode in which, at a remote period, the races of mankind became differentiated, is declared to be the weak point in the argument.