The rapidly growing interest in Eugenics, and the scientific consideration of the world-wide decline in the birth-rate have drawn attention to the study of the eugenic factors which determine the production of high ability in offspring. Many distinguished investigators have conducted long and exhaustive investigations for the purpose of ascertaining and summarizing all possible biological data concerning the parentage and birth of the most notable persons born in European countries, and to a lesser extent in America.
The investigations are now acquiring a fresh importance, because, while it is becoming recognized that we are gaining a control over the conditions of birth, the production of children has itself gained an importance. The world is no longer to be bombarded by an exuberant stream of babies, good, bad, and indifferent in quality, with mankind to look on calmly at the struggle for existence among them. Whether we like it or not, the quantity is steadily diminishing, and the question of quality is beginning to assume a supreme significance. The question then is being anxiously asked: "What are the conditions which assure the finest quality in our children?"
A German scientist, Dr. Vaerting, of Berlin, published just before the War a treatise on the subject of the most favorable age in parents for the production of offspring of ability. He treated the question in an entirely new spirit, not merely as a matter of academic discussion, but rather as a practical matter of vital importance to the welfare of modern society. He starts by asserting that "our century has been called the century of the child," and that for the child all manner of rights are now being claimed. But, he wisely adds, there is seldom considered the prime right of all the child's rights, i. e., the right of the child to the best ability and capacity for efficiency that his parents are able to transmit to him. The good doctor adds that this right is the root of all children's rights; and that when the mysteries of procreation have been so far revealed as to enable this right to be won, we shall, at the same time renew the spiritual aspect of the nations.
The writer referred to decided that the most easily ascertainable and measurable factor in the production of ability, and efficiency in offspring, and a factor of the greatest significance, is the age of the parents at the child's birth. He investigated a number of cases of men of ability and efficiency, along these lines, and made a careful summary of his results. Some of his results are somewhat startling, and may possibly require the corroboration of other investigators before they can be accepted as authoritative; but they are worthy of being carefully considered at the present time, pending such further investigation.
Vaerting found that the fathers who were themselves not notably intellectual have a decidedly more prolonged power of procreating distinguished children than is possessed by distinguished fathers. The former may become the fathers of eminent children from the period of sexual maturity up to the age of forty-three or beyond. When, however, the father is himself of high intellectual distinction, the records show that he was nearly always under thirty, and usually under twenty-five years of age at the time of the birth of his distinguished son, although the proportion of youthful fathers in the general population is relatively small. The eleven youngest fathers on Vaerting's list, from twenty-one to twenty-five years of age, were with one exception themselves more or less distinguished; while the fifteen oldest, from thirty-nine to sixty years of age, were all without exception undistinguished.
Among the sons on the latter list are to be found much greater names (such as Goethe, Bach, Kant, Bismarck, Wagner, etc.) than are to be found among the sons of young and more distinguished fathers, for here is only one name (Frederick the Great) of the same caliber. The elderly fathers belonged to the large cities, and were mostly married to wives very much younger than themselves. Vaerting notes that the most eminent men have frequently been the sons of fathers who were not engaged in intellectual avocations at all, but earned their living as humble craftsmen. He draws the conclusion from these data that strenuous intellectual energy is much more unfavorable than hard physical labor to the production of marked ability in the offspring. Intellectual workers, therefore, he argues, must have their children when young, and we must so modify our social ideals and economic conditions as to render this possible.
Vaerting, however, holds that the mother need not be equally young; he finds some superiority, indeed, provided the father is young, in somewhat elderly mothers, and there were no mothers under twenty-three on the list. The rarity of genius among the offspring of distinguished parents he attributes to the unfortunate tendency to marry too late; and he finds that the distinguished men who marry late rarely have any children at all. Speaking generally, and apart from the production of genius, he holds that women have children too early, before their psychic development is completed, while men have children too late, when they have already "in the years of their highest psychic generative fitness planted their most precious seed in the mud of the street."
The eldest child was found to have by far the best chance of turning out distinguished, and in this fact Vaerting finds further proof of his argument. The third son has the next best chance, and then the second, the comparatively bad position of the second being attributed to the too brief interval which often follows the birth of the first child. He also notes that of all the professions the clergy come beyond comparison first as the parents of distinguished sons (who are, however, rarely of the highest degree of eminence), lawyers following, while officers in the army and physicians scarcely figure at all. Vaerting is inclined to see in this order, especially in the predominance of the clergy, the favorable influence of an unexhausted reserve of energy and a habit of chastity on intellectual procreativeness.
It should be remembered, however, that Vaerting's cases on his list were all those of Germans, and, therefore, the influence of the characteristic social customs and conditions of the German people must be taken into account in the consideration.
Havelock Ellis in his well known work "Study of British Genius" dealt on a still larger scale, and with a somewhat more precise method, with many of the same questions as illustrated by British cases. After the publication of Vaerting's work, Ellis re-examined his cases, and rearranged his data. His results, like those of the German authority, showed a special tendency for genius to appear in the eldest child, though there was no indication of notably early marriage in the parents. He also found a similar predominance of the clergy among the fathers, and a similar deficiency of army officers and physicians.