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spring suggests the two-sided responsibility of parentage; but the fact has to be corrected by Galton's statistical conclusion that the offspring inherits a fourth from each parent, and a sixteenth from each grandparent! Inherited capital is not merely dual, but multiple like a mosaic.

If we adopt a modified form of Weismann's conclusion, and believe that only the more deeply penetrating acquired characters are transmitted, we are saved from the despair suggested by the abnormal functions and environments of our civilisation.

And just in proportion as we doubt the transmission of desirable acquired characters, so much the more should we desire to secure that improved conditions of life foster the individual development of each successive generation.

That pathological conditions, innate or congenital in the organism, tend to be transmitted, suggests that men should be informed and educated as to the undesirability of parentage on the part of abnormal members of the community.

But while no one will gainsay the lessons to be drawn from the experience of past generations, it should be noticed that Virchow and others have hinted at an "optimism of pathology," since some of the less adequately known abnormal variations may be associated with new beginnings not without promise of possible utility. It seems, moreover, that by careful environment and function, or by the intercrossing of a slightly tainted and a relatively pure stock, a recuperative or counteractive influence may act so as to produce comparatively healthy offspring, thus illustrating what may be called "the forgiveness of nature."

6. Social Inheritance. The widest problems of heredity are raised when we substitute "fraternities" for individuals, or make the transition to social inheritance— the relation between the successive generations of a society.

The most important pioneering work is that of Galton, whose unique papers have been recently summed up in a work entitled Natural Inheritance. Galton derived his data from his Records of Family Faculties, especially concerning stature, eye-colour, and artistic powers; and his

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work has been in great part an application of the statistical law of Frequency of Error to the records accumulated.

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The main problem of his work is concerned with the strange regularity observed in the peculiarities of great populations throughout a series of generations. large do not always beget the large, nor the small the small; but yet the observed proportion between the large and the small, in each degree of size and in every quality hardly varies from one generation to another." A specific average is sustained. This is not because each individual leaves his like behind him, for this is not the case. It is rather due to the fact of a regular regression or deviation which brings the offspring of extraordinary parents in a definite ratio nearer the average of the stock.

"However paradoxical it may appear at first sight, it is theoretically a necessary fact, and one that is clearly confirmed by observation, that the stature of the adult offspring must on the whole be more mediocre than the stature of their parents that is to say, more near to the median stature of the general population. Each peculiarity of a man is shared by his kinsmen, but on an average in a less degree. It is reduced to a definite fraction of its amount, quite independently of what its amount might be. The fraction differs in different orders of kinship, becoming smaller as they are more remote."

Yet it must not be supposed that the value of a good stock is under-estimated by Galton, for he shows how the offspring of two ordinary members of a gifted stock will not regress like the offspring of a couple equal in gifts to the former, but belonging to a poorer stock, above the average of which they have risen.

Yet the fact of regression tells against the full transmission of any signal talent. Children are not likely to differ from mediocrity so widely as their parents. "The more bountifully a parent is gifted by nature, the more rare will be his good fortune if he begets a son who is as richly endowed as himself, and still more so if he has a son who is endowed more largely." But "The law is even-handed; it levies an equal succession-tax on the transmission of badness as of

goodness. If it discourages the extravagant hope of a gifted parent that his children will inherit all his powers, it no less discountenances extravagant fears that they will inherit all his weakness and disease."

The study of individual inheritance, as in Galton's Hereditary Genius, may tend to develop an aristocratic and justifiable pride of race when a gifted lineage is verifiable for generations. It may lead to despair if the records of family diseases be subjected to investigation.

But the study of social inheritance is at once more democratic and less pessimistic. The nation is a vast fraternity, with an average towards which the noble tend, but to which the offspring of the under-average as surely approximate. Measures which affect large numbers are thus more hopeful than those which artificially select a few.

Even when we are doubtful as to the degree in which acquired characters are transmissible, we cannot depreciate the effect on individuals of their work and surroundings. In fact there should be the more earnestness in our desire to conserve healthful function and stimulating environment of every kind, for these are not less important if their influences must needs be repeated on each fresh generation. "There was a child went forth every day; and the first object he looked upon, that object he became; and that object became part of him for the day, or a certain part of the day, or for many years, or for stretching cycles of years." 1

Nor can we forget how much a plastic physical and mental education may do to counteract disadvantageous inherited qualities, or to strengthen characters which are useful.

Every one will allow at least that much requires to be done in educating public opinion, not only to recognise all the facts known in regard to heredity, but also to admit the value and necessity of the art which Mr. Galton calls "eugenics," or in frank English "good-breeding."

1 Walt Whitman's "Assimilations."

APPENDIX I

ANIMAL LIFE AND OURS

A. Our Relation to Animals

1. Affinities and Differences between Man and Monkeys. In one of the works of Broca, a pioneer anthropologist of renown, there is an eloquent apology for those who find it useful to consider man's zoological relations.

66 Pride," he says, "which is one of the most characteristic traits of our nature, has prevailed with many minds over the calm testimony of reason. Like the Roman emperors who, enervated by all their power, ended by denying their character as men, in fact, by believing themselves demigods, so the king of our planet pleases himself by imagining that the vile animal, subject to his caprices, cannot have anything in common with his peculiar nature. The proximity of the monkey vexes him, it is not enough to be king of animals; he wishes to separate himself from his subjects by a deep unfathomable abyss; and, turning his back upon the earth, he takes refuge with his menaced majesty in a nebulous sphere, 'the human kingdom.' But anatomy, like that slave who followed the conqueror's chariot crying, Memento te hominem esse, anatomy comes to trouble man in his naïve self-admiration, reminding him of the visible tangible facts which bind him to the animals."

Let us hearken to this slave a little, remembering Pascal's maxims: "It is dangerous to show man too plainly how like he is to the animals, without, at the same time, reminding him of his greatness. It is equally unwise to impress him with his greatness, and not with his lowliness. It is worse to leave him in ignorance of both. But it is very profitable to recognise the two facts."

It is many years since Owen-now a veteran among anatomists -described the "all-pervading similitude of structure" between

man and the highest monkeys. Subsequent research has continued to add corroborating details. As far as structure is concerned, there is much less difference between man and the gorilla than between the gorilla and a monkey like a marmoset. Yet differences between man and the anthropoid apes do exist. Thus man alone is thoroughly erect after his infancy is past, his head weighted with a heavy brain does not droop forward, and with his erect attitude his perfect development of vocal mechanism is perhaps connected. We plant the soles of our feet flat on the ground, our great toes are usually in a line with the rest, and we have better heels than monkeys have, but no emphasis can be laid on the old distinction which separated two-handed men (Bimana) from the four-handed monkeys (Quadrumana), nor on the fact that man is peculiarly naked. We have a bigger forehead, a less protrusive face, smaller cheek-bones and eyebrow ridges, a true chin, and more uniform teeth than the anthropoid apes. More important, however, is the fact that the weight of the gorilla's brain bears to that of the smallest brain of an adult man the ratio of 2 : 3, and to the largest human brain the ratio of 1: 3; in other words, a man may have a brain three times as heavy as that of a gorilla. The brain of a healthy human adult never weighs less than 31 or 32 ounces; the average human brain weighs 48 or 49 ounces; the heaviest gorilla brain does not exceed 20 ounces. "The cranial capacity is never less than 55 cubic inches in any normal human subject, while in the orang and the chimpanzee it is but 26 and 27 cubic inches respectively."

But differences which can be measured and weighed give us little hint of the characteristically human powers of building up ideas and of cherishing ideals. It is not merely that man profits by his experience, as many animals do, but that he makes some kind of theory of it. It is not merely that he works for ends which are remote, as do birds and beavers, but that he controls his life according to conscious ideals of conduct. But I need not say much in regard to the characteristics of human personality, we are all conscious of them, though we may differ as to the words in which they may be expressed; nor need I talk about man's power of articulate speech, nor his realisation of history, nor his inherent social sympathies, nor his gentleness. For all recognise that the higher life of men has a loftier pitch than that of animals, while many think that the difference is in kind, not merely in degree.

2. Descent of Man.-The arguments by which Darwin and others have sought to show that man arose from an ancestral type common to him and to the higher apes are the same as those used to substantiate the general doctrine of descent. For the Descent of Man was but the expansion of a chapter in the Origin of Species ;

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