Читать книгу Applied Eugenics - Paul Popenoe - Страница 19

There is, then, a suspicion that lead is a racial poison, but no evidence as yet as to whether the effect is permanent or in the nature of an induction.

This concludes the short list of substances for which there has been any plausible case made out, as racial poisons. Gonorrhea, malaria, arsenic, tobacco, and numerous other substances have been mentioned from time to time, and even ardently contended by propagandists to be racial poisons, but in the case of none of them, so far as we know, is there any evidence to support the claim. And as has been shown, in the case of the three chief so-called racial poisons, alcohol, syphilis and lead, the evidence is not great. We are thus in a position to state that, from the eugenists' point of view, the origination of degeneracy, by some direct action of the germ-plasm, is a contingency that hardly needs to be reckoned with. Even in case the evidence were much stronger than it is, the damage done may only be a physiological or chemical induction, the effects of which will wear off in a few generations; rather than a radical change in the hereditary constituents of the germ-plasm. The germ-plasm is so carefully isolated and guarded that it is almost impossible to injure it, except by treatment so severe as to kill it altogether; and the degeneracy with which eugenists are called on to deal is a degeneracy which is running along from generation to generation and which, when once stopped by the cessation of reproduction, is in little danger of being originated anew through some racial poison.

Through these facts, the problem of race betterment is not only immensely simplified, but it is clearly shown to be more a matter for treatment by the biologist, acting through eugenics, than for the optimistic improver of the environment.

There is another way in which it is widely believed that some such result as a direct influence of the germ-plasm can be produced: that is through the imaginary process known as maternal impression, prenatal influence, etc. Belief in maternal impressions is no novelty. In the book of Genesis[24] Jacob is described as making use of it to get the better of his tricky father-in-law. Some animal breeders still profess faith in it as a part of their methods of breeding: if they want a black calf, for instance, they will keep a white cow in a black stall, and express perfect confidence that her offspring will resemble midnight darkness. It is easy to see that this method, if it "works," would be a potent instrument for eugenics. And it is being recommended for that reason. Says a recent writer, who professes on the cover of her book to give a "complete and intelligent summary of all the principles of eugenics":

"Too much emphasis can not be placed upon the necessity of young people making the proper choice of mates in marriage; yet if the production of superior children were dependent upon that one factor, the outlook would be most discouraging to prospective fathers and mothers, for weak traits of character are to be found in all. But when young people learn that by a conscious endeavor to train themselves, they are thereby training their unborn children, they can feel that there is some hope and joy in parentage; that it is something to which they can look forward with delight and even rapture; then they will be inspired to work hard to attain the best and highest that there is in them, leading the lives that will not only be a blessing to themselves, but to their succeeding generation."

The author of this quotation has no difficulty in finding supporters. Many physicians and surgeons, who are supposed to be trained in scientific methods of thought, will indorse what she says. The author of one of the most recent and in many respects admirable books on the care of babies, is almost contemptuous in her disdain for those who think otherwise:

"Science wrangles over the rival importance of heredity and environment, but we women know what effects prenatal influence works on children." "The woman who frets brings forth a nervous child. The woman who rebels generally bears a morbid child." "Self-control, cheerfulness and love for the little life breathing in unison with your own will practically insure you a child of normal physique and nerves."

Such statements, backed up by a great array of writers and speakers whom the layman supposes to be scientific, and who think themselves scientific, can not fail to influence strongly an immense number of fathers and mothers. If they are truly scientific statements, their general acceptance must be a great good.

But think of the misplaced effort if these widespread statements are false!

Is there, or is there not, a short cut to race betterment? Everyone interested in the welfare of the race must feel the necessity of getting at the truth in the case; and the truth can be found only by rigorously scientific thought.

Let us turn to the observed facts. This sample is taken from the health department of a popular magazine, quite recently issued:

"Since birth my body has been covered with scales strikingly resembling the surface of a fish. My parents and I have expended considerable money on remedies and specialists without deriving any permanent benefit. I bathe my entire body with hot water daily, using the best quality of soap. The scales fall off continually. My brother, who is younger than myself, is afflicted with the same trouble, but in a lesser degree. My sister, the third member of the family, has been troubled only on the knees and abdomen. My mother has always been quite nervous and susceptible to any unusual mental impression. She believes that she marked me by craving fish, and preferring to clean them herself. During the prenatal life of my brother, she worried much lest she might mark him in the same way. In the case of my sister she tried to control her mind."[25]

Another is taken from a little publication which is devoted to eugenics.[26] As a "horrible example" the editor gives the case of Jesse Pomeroy, a murderer whom older readers will remember. His father, it appears, worked in a meat market. Before the birth of Jesse, his mother went daily to the shop to carry a luncheon to her husband, and her eyes naturally fell upon the bloody carcases hung about the walls. Inevitably, the sight of such things would produce bloody thoughts in the mind of the unborn child!

These are extreme cases; we quote from a medieval medical writer another case that carries the principle to its logical conclusion: A woman saw a Negro—at that time a rarity in Europe. She immediately had a sickening suspicion that her child would be born with a black skin. To obviate the danger, she had a happy inspiration—she hastened home and washed her body all over with warm water. When the child appeared, his skin was found to be normally white—except between the fingers and toes, where it was black. His mother had failed to wash herself thoroughly in those places!

Of course, few of the cases now credited are as gross as this, but the principle involved remains the same.

We will take a hypothetical case of a common sort for the sake of clearness: the mother receives a wound on the arm; when her child is born it is found to have a scar of some sort at about the same place on the corresponding arm. Few mothers would fail to see the result of a maternal impression here. But how could this mark have been transmitted? This is not a question of the transmission of acquired characters through the germ-plasm, or anything of that sort, for the child was already formed when the mother was injured. One is obliged, therefore, to believe that the injury was in some way transmitted through the placenta, the only connection between the mother and the unborn child; and that it was then reproduced in some way in the child.

Here is a situation which, examined in the cold light of reason, puts a heavy enough strain on the credulity. Such an influence can reach the embryo only through the blood of the mother. Is it conceivable to any rational human being, that a scar, or what not, on the mother's body can be dissolved in her blood, pass through the placenta into the child's circulation, and then gather itself together into a definite scar on the infant's arm?

There is just as much reason to expect the child to grow to resemble the cow on whose milk it is fed after birth, as to expect it to grow to resemble its mother, because of prenatal influence, as the term is customarily used, for once development has begun, the child draws nothing more than nourishment from its mother.

Of course we are accustomed to the pious rejoinder that man must not expect to understand all the mysteries of life; and to hear vague talk about the wonder of wireless telegraphy. But wireless telegraphy is something very definite and tangible—there is little mystery about it. Waves of a given frequency are sent off, and caught by an instrument attuned to the same frequency. How any rational person can support a belief in maternal impressions by such an analogy, if he knows anything about anatomy and physiology, passes comprehension.

Now we are far from declaring that a reason can be found for everything that happens. Science does not refuse belief in an observed fact merely because it is unexplainable. But let us examine this case of maternal impressions a little further. What can be learned of the time element?

Immediately arises the significant fact that most of the marks, deformities and other effects which are credited to prenatal influence must on this hypothesis take place at a comparatively late period in the antenatal life of the child. The mother is frightened by a dog; the child is born with a dog-face. If it be asked when her fright occurred, it is usually found that it was not earlier than the third month, more likely somewhere near the sixth.

But it ought to be well known that the development of all the main parts of the body has been completed at the end of the second month. At that time, the mother rarely does more than suspect the coming of the child, and events which she believes to "mark" the child, usually occur after the fourth or fifth month, when the child is substantially formed, and it is impossible that many of the effects supposed to occur could actually occur. Indeed, it is now believed that most errors of development, such as lead to the production of great physical defects, are due to some cause within the embryo itself, and that most of them take place in the first three or four weeks, when the mother is by no means likely to influence the course of embryological development by her mental attitude toward it, for the very good reason that she knows nothing about it.

Unless she is immured or isolated from the world, nearly every expectant mother sees many sights of the kind that, according to popular tradition, cause "marks." Why is it that results are so few? Why is it that women doctors and nurses, who are constantly exposed to unpleasant sights, have children that do not differ from those of other mothers?

Darwin, who knew how to think scientifically, saw that this is the logical line of proof or disproof. When Sir Joseph Hooker, the botanist and geologist who was his closest friend, wrote of a supposed case of maternal impression, one of his kinswomen having insisted that a mole which appeared on her child was the effect of fright upon herself for having, before the birth of the child, blotted with sepia a copy of Turner's Liber Studiorum that had been lent her with special injunctions to be careful, Darwin[27] replied: "I should be very much obliged, if at any future or leisure time you could tell me on what you ground your doubtful belief in imagination of a mother affecting her offspring. I have attended to the several statements scattered about, but do not believe in more than accidental coincidences. W. Hunter told my father, then in a lying-in hospital, that in many thousand cases he had asked the mother, before her confinement, whether anything had affected her imagination, and recorded the answers; and absolutely not one case came right, though, when the child was anything remarkable, they afterwards made the cap to fit."

Any doctor who has handled many maternity cases can call to mind instances where every condition was present to perfection, for the production of maternal impression, on the time-honored lines. None occurred. Most mothers can, if they give the matter careful consideration, duplicate this experience from their own. Why is it that results are so rare?

That Darwin gave the true explanation of a great many of the alleged cases is perfectly clear to us. When the child is born with any peculiar characteristic, the mother hunts for some experience in the preceding months that might explain it. If she succeeds in finding any experience of her own at all resembling in its effects the effect which the infant shows, she considers she has proved causation, has established a good case of prenatal influence.

It is not causation; it is coincidence.

If the prospective mother plays or sings a great deal, with the idea of giving her child a musical endowment, and the child actually turns out to have musical talent, the mother at once recalls her yearning that such might be the case; her assiduous practice which she hoped would be of benefit to her child. She immediately decides that it did benefit him, and she becomes a convinced witness to the belief in prenatal culture. Has she not herself demonstrated it?

She has not. But if she would examine the child's heredity, she would probably find a taste for music running in the germ-plasm. Her study and practice had not the slightest effect on this hereditary disposition; it is equally certain that the child would have been born with a taste for music if its mother had devoted eight hours a day for nine months to cultivating thoughts of hatred for the musical profession and repugnance for everything that possesses rhythm or harmony.

It necessarily follows, then, that attempts to influence the inherent nature of the child, physically or mentally, through "prenatal culture," are doomed to disappointment. The child develops along the lines of the potentialities which existed in the two germ-cells that united to become its origin. The course of its development can not be changed in any specific way by any corresponding act or attitude of its mother, good hygiene alone need be her concern.

It must necessarily follow that attempts to improve the race on a large scale, by the general adoption of prenatal culture as an instrument of eugenics, are useless.

Indeed, the logical implication of the teaching is the reverse of eugenic. It would give a woman reason to think she might marry a man whose heredity was most objectionable, and yet, by prenatal culture, save her children from paying the inevitable penalty of this weak heritage. The world has long shuddered over the future of the girl who marries a man to reform him; but think what it means to the future of the race if a superior girl, armed with correspondence school lessons in prenatal culture, marries a man to reform his children!

Those who practice this doctrine are doomed to disillusion. The time they spend on prenatal culture is not cultivating the child; it is merely perpetuating a fallacy. Not only is their time thus spent wasted, but worse, for they might have employed it in ways that really would have benefited the child—in open-air exercise, for instance.

To recapitulate, the facts are:

(1) That there is, before birth, no connection between mother and child, by which impressions on the mother's mind or body could be transmitted to the child's mind or body.

(2) That in most cases the marks or defects whose origin is attributed to maternal impression, must necessarily have been complete long before the incident occurred which the mother, after the child's birth, ascribes as the cause.

(3) That these phenomena usually do not occur when they are, and by hypothesis ought to be, expected. The explanations are found after the event, and that is regarded as causation which is really coincidence.

Pre-natal care as a euthenic measure is of course not only legitimate but urgent. The embryo derives its entire nourishment from the mother; and its development depends wholly on its supply of nourishment. Anything which affects the supply of nourishment will affect the embryo in a general, not a particular way. If the mother's mental and physical condition be good, the supply of nourishment to the embryo is likely to be good, and development will be normal. If, on the other hand, the mother is constantly harassed by fear or hatred, her physical health will suffer, she will be unable properly to nourish her developing offspring, and it may be its poor physical condition when born, indicates this.

Further, if the mother experiences a great mental or physical shock, it may so upset her health that her child is not properly nourished, its development is arrested, mentally as well as physically, and it is born defective. H. H. Goddard, for example, tells[28] of a high-grade imbecile in the Training School at Vineland, N. J. "Nancy belongs to a thoroughly normal, respectable family. There is nothing to account for the condition unless one accepts the mother's theory. While it sounds somewhat like the discarded theory of maternal impression, yet it is not impossible that the fright and shock which the mother received may have interfered with the nutrition of the unborn child and resulted in the mental defect. The story in brief is as follows. Shortly before this child was born, the mother was compelled to take care of a sister-in-law who was in a similar condition and very ill with convulsions. Our child's mother was many times frightened severely as her sister-in-law was quite out of her mind."

It is easily understandable that any event which makes such an impression on the mother as to affect her health, might so disturb the normal functioning of her body that her child would be badly nourished, or even poisoned. Such facts undoubtedly form the basis on which the airy fabric of prenatal culture was reared by those who lived before the days of scientific biology.

Thus, it is easy enough to see the real explanation of such cases as those mentioned near the beginning of this discussion. The mothers who fret and rebel over their maternity, she found, are likely to bear neurotic children. It is obvious (1) that mothers who fret and rebel are quite likely themselves to be neurotic in constitution, and the child naturally gets its heredity from them: (2) that constant fretting and rebellion would so affect the mother's health that her child would not be properly nourished.

When, however, she goes on to draw the inference that "self-control, cheerfulness and love … will practically insure you a child normal in physique and nerves," we are obliged to stop. We know that what she says is not true. If the child's heredity is bad, neither self-control, cheerfulness, love, nor anything else known to science, can make that heredity good.

At first thought, one may wish it were otherwise. There is something inspiring in the idea of a mother overcoming the effect of heredity by the sheer force of her own will-power. But perhaps in the long run it is as well; for there are advantages on the other side. It should be a satisfaction to mothers to know that their children will not be marked or injured by untoward events in the antenatal days; that if the child's heredity can not be changed for the better, neither can it be changed for the worse.

The prenatal culturists and maternal-impressionists are trying to place on her a responsibility which she need not bear. Obviously, it is the mother who is most nearly concerned with the bogy of maternal impressions, and it should make for her peace of mind to know that it is nothing more than a bogy. It is important for the expectant mother to keep herself in as nearly perfect condition as possible, both physically and mentally. Her bodily mechanism will then run smoothly, and the child will get from her blood the nourishment needed for its development. Beyond that there is nothing the mother can do to influence the development of her child.

There is another and somewhat similar fallacy which deserves a passing word, although it is of more concern to the livestock breeder than to the eugenist. It is called telegony and is, briefly, this: that conception by a female results in a definite modification of her germ-plasm from the influence of the male, and that this modification will be shown in the offspring she may subsequently bear to a second male. The only case where it is often invoked in the human race is in miscegenation. A white woman has been married to a Negro, for instance, and has borne one or more mulatto offspring. Subsequently, she mates with a white man; but her children by him, instead of being pure white, it is alleged, will be also mulattoes. The idea of telegony, the persistent influence of the first mating, may be invoked to explain this discrepancy.

It is a pure myth. There is no good evidence[29] to support it, and there is abundant evidence to contradict it. Telegony is still believed by many animal breeders, but it has no place in science. In such a case as the one quoted, the explanation is undoubtedly that the supposed father is not the real one; and this explanation will dispose of all other cases of telegony which can not be explained, as in most instances they can be, by the mixed ancestry of the offspring and the innate tendency of all living things to vary.

Now to sum up this long chapter. We started with a consideration of the germ-plasm, the physical basis of life; pointing out that it is continuous from generation to generation, and potentially immortal; that it is carefully isolated and guarded in the body, so that it is not likely to be injured by any ordinary means.

One of the logical results of this continuity of the germ-plasm is that modifications of the body of the parent, or acquired characters, can hardly be transferred to the germ-plasm and become a part of the inheritance. Further the experimental evidence upholds this position, and the inheritance of acquired body characters may be disregarded by eugenics, which is therefore obliged to concern itself solely with the material already in existence in the germ-plasm, except as that material may be changed by variation which can neither be predicted nor controlled.

The evidence that the germ-plasm can be permanently modified does not warrant the belief; and such results, if they exist at all, are not large enough or uniform enough to concern the eugenist.

Pre-natal culture and telegony were found to be mere delusions. There is no justification for hoping to influence the race for good through the action of any kind of external influences; and there is not much danger of influencing it for ill through these external influences. The situation must be faced squarely then: if the race is to be improved, it must be by the use of the material already in existence; by endeavor to change the birth-and death-rates so as to alter the relative proportions of the amounts of good and bad germ-plasm in the race. This is the only road by which the goal of eugenics can be reached.