The question of inherited immunity to diseases, as the result of vaccination or actual illness from them, has appeared in the controversy in a number of forms, and is a point of much importance. It is not yet clear, partly because the doctors disagree as to what immunity is. But there is no adequate evidence that an immunity to anything can be created and transmitted through the germ-plasm to succeeding generations.
In short, no matter what evidence we examine, we must conclude that inheritance of acquired bodily characters is not a subject that need be reckoned with, in applied eugenics.
On the other hand, there is a possible indirect influence of modifications, which may have real importance in man. If the individual is modified in a certain way, in a number of generations, even though such a modification is not transmitted to his descendants, yet its continued existence may make possible, the survival of some germinal variation bearing in the same direction, which without the protecting influence of the pre-existing modification, would have been swamped or destroyed.
Finally, it should be borne in mind that even if physical and mental characters acquired during a man"s lifetime are not transmitted, yet there is a sort of transmission of acquired characters which has been of immense importance to the evolution of the race. This is the so-called "inheritance" of the environment; the pa.s.sing on from one generation to the next of the achievements of the race, its acc.u.mulated social experience; its civilization, in short. It is doubtful whether any useful end is gained by speaking of this continuance of the environment as "heredity;" it certainly tends to confuse many people who are not used to thinking in biological terms. Tradition is the preferable term.
There is much to be said in favor of E. B. Poulton"s definition,--"Civilization in general is the sum of those contrivances which enable human beings to advance independently of heredity."
Whatever wisdom, material gain, or language is acquired by one generation may be pa.s.sed on to the next. As far as the environment is concerned, one generation stands on the shoulders of its predecessor.
It might simplify the task of eugenics if the same could be said of biological heredity. But it can not. Each generation must "start from scratch."
In August Weismann"s words, the development of a function in offspring begins at the point where it _began_ in his parents, not at the point where it _ended_ in them. Biological improvement of the race (and such improvement greatly fosters all other kinds) must be made through a selective birth-rate. There is no short-cut by way of euthenics, merely.
We must now consider whether there is any direct way of impairing good heredity. It is currently believed that there are certain substances, popularly known as "racial-poisons," which are capable of affecting the germ-plasm adversely and permanently in spite of its isolation and protection. For example, the literature of alcoholism, and much of the literature of eugenics, abounds with statements to the effect that alcohol _originates_ degeneracy in the human race.
The proof or disproof of this proposition must depend in the last a.n.a.lysis on direct observation and carefully controlled experiments. As the latter cannot be made feasibly on man, a number of students have taken up the problem by using small animals which are easily handled in laboratories. Many of these experiments are so imperfect in method that, when carefully examined, they are found to possess little or no value as evidence on the point here discussed.
Hodge, Mairet and Combemale, for example, have published data which convinced them that the germ-plasm of dogs was injured by the administration of alcohol. The test was the quality of offspring directly produced by the intoxicated animals under experiment. But the number of dogs used was too small to be conclusive, and there was no "control": hence these experiments carry little weight.
Ovize, Fere and Stockard have shown that the effect of alcohol on hen"s eggs is to produce malformed embryos. This, however, is a case of influencing the development of the individual, rather than the germ-plasm. Evidence is abundant that individual development can be harmed by alcohol, but the experiments with eggs are not to the point of our present purpose.
Carlo Todde and others have carried out similar experiments on c.o.c.ks.
The conclusions have in general been in favor of injury to the germ-plasm, but the experiments were inadequate in extent.
Laitinen experimented on rabbits and guinea pigs, but he used small doses and secured only negative results.
Several series of experiments with rats indicate that if the dosage is large enough, the offspring can be affected.
Nice, using very small numbers of white mice, subjected them not only to alcohol, but to caffein, nicotin, and tobacco smoke. The fecundity of all these sets of mice was higher than that of the untreated ones used as control; all of them gained in weight; of 707 young, none was deformed, none stillborn, and there was only one abortion. The young of the alcoholized mice surpa.s.sed all others in growth. The dosage Nice employed was too small, however, to give his experiment great weight.
At the University of Wisconsin, Leon J. Cole has been treating male rabbits with alcohol and reports that "what appear to be decisive results have already been obtained. In the case of alcoholic poisoning of the male the most marked result has been a lessening of his efficiency as a sire, the alcohol apparently having had some effect on the vitality of his spermatozoa." His experiment is properly planned and carried out, but so far as results have been made public, they do not appear to afford conclusive evidence that alcohol originates degeneracy in offspring.
The long-continued and carefully conducted experiment of Charles R.
Stockard at the Cornell Medical College is most widely quoted in this connection. He works with guinea-pigs. The animals are intoxicated daily, six days in the week, by inhaling the fumes of alcohol to the point where they show evident signs of its influence; their condition may thus be compared to that of the toper who never gets "dead drunk"
but is never entirely sober. Treatment of this sort for a period as long as three years produces no apparent bad effect on the individuals; they continue to grow and become fat and vigorous, taking plenty of food and behaving in a normal manner in every particular. Some of them have been killed from time to time, and all the tissues, including the reproductive glands, have been found perfectly normal. "The treated animals are, therefore, little changed or injured so far as their behavior and structure goes. Nevertheless, the effects of the treatment are most decidedly indicated by the type of offspring to which they give rise, whether they are mated together or with normal individuals."
Before the treatment is begun, every individual is mated at least once, to demonstrate its possibility of giving rise to sound offspring. The crucial test of the influence of alcohol on the germ-cells is, of course, the mating of a previously alcoholized male with a normal, untreated female, in a normal environment.
When the experiment was last reported,[16] it had covered five years and four generations. The records of 682 offspring produced by 571 matings were tabulated, 164 matings of alcoholized animals, in which either the father, mother, or both were alcoholic, gave 64, or almost 40%, negative results or early abortions, while only 25% of the control matings failed to give full-term litters. Of the 100 full-term litters from alcoholic parents 18% contained stillborn young and only 50% of all the matings resulted in living litters, while 47% of the individuals in the litters of living young died soon after birth. In contrast to this record 73% of the 90 control matings gave living litters and 84% of the young in these litters survived as normal, healthy animals.
"The mating records of the descendants of the alcoholized guinea pigs, although they themselves were not treated with alcohol, compare in some respects even more unfavorably with the control records than do the above data from the directly alcoholized animals." The records of the matings in the second filial generation "are still worse, higher mortality and more p.r.o.nounced deformities, while the few individuals which have survived are generally weak and in many instances appear to be quite sterile even though paired with vigorous, prolific, normal mates."
We do not minimize the value of this experiment, when we say that too much weight has been popularly placed on its results. Compare it with the experiment with fowls at the University of Maine, which Raymond Pearl reports.[17] He treated 19 fowls with alcohol, little effect on the general health being shown, and none on egg production. From their eggs 234 chicks were produced; the average percentage of fertility of the eggs was diminished but the average percentage of hatchability of fertile eggs was increased. The infant mortality of these chicks was smaller than normal, the chicks were heavier when hatched and grew more rapidly than normal afterwards. No deformities were found. "Out of 12 different characters for which we have exact quant.i.tative data, the offspring of treated parents taken as a group are superior to the offspring of untreated parents in 8 characters," in two characters they are inferior and in the remaining two there is no discernible difference. At this stage Dr. Pearl"s experiment is admittedly too small, but he is continuing it. As far as reported, it confirms the work of Professor Nice, above mentioned, and shows that what is true for guinea pigs may not be true for other animals, and that the amount of dosage probably also makes a difference. Dr. Pearl explains his results by the hypothesis that the alcohol eliminated the weaker germs in the parents, and allowed only the stronger germs to be used for reproduction.
Despite the unsatisfactory nature of much of the alleged evidence, we must conclude that alcohol, when given in large enough doses, may sometimes affect the germ-plasm of some lower animals in such a way as to deteriorate the quality of their offspring. This effect is probably an "induction," which does not produce a permanent change in the bases of heredity, but will wear away in a generation or two of good surroundings. It must be remembered that although the second-generation treated males of Dr. Stockard"s experiment produced defective offspring when mated with females from similarly treated stock, they produced normal offspring when mated with normal females. The significance of this fact has been too little emphasized in writings on "racial poisons." If a normal mate will counteract the influence of a "poisoned"
one, it is obvious that the probabilities of danger to any race from this source are much decreased, while if only a small part of the race is affected, and mates at random, the racial damage might be so small that it could hardly be detected.
There are several possible explanations of the fact that injury is found in some experiments but not in others. It may be, as Dr. Pearl thinks, that only weak germs are killed by moderate treatment, and the strong ones are uninjured. And it is probable (this applies more particularly to man) that the body can take care of a certain amount of alcohol without receiving any injury therefrom; it is only when the dosage pa.s.ses the "danger point" that the possibility of injury appears. As to the location of this limit, which varies with the species, little is known. Much more work is needed before the problem will be fully cleared up.
Alcohol has been in use in parts of the world for many centuries; it was common in the Orient before the beginning of historical knowledge. Now if its use by man impairs the germ-plasm, then it seems obvious that the child of one who uses alcohol to a degree sufficient to impair his germ-plasm will tend to be born inferior to his parent. If that child himself is alcoholic, his own offspring will suffer still more, since they must carry the burden of two generations of impairment. Continuing this line of reasoning over a number of generations, in a race where alcohol is freely used by most of the population, one seems unable to escape from the conclusion that the effects of this racial poison, if it be such, must necessarily be c.u.mulative. The damage done to the race must increase in each generation. If the deterioration of the race could be measured, it might even be found to grow in a series of figures representing arithmetical progression.
It seems impossible, with such a state of affairs, that a race in which alcohol was widely used for a long period of time, could avoid extinction. At any rate, the races which have used alcohol longest ought to show great degeneracy--unless there be some regenerative process at work constantly counteracting this c.u.mulative effect of the racial poison in impairing the germ-plasm.
Such a proposition at once demands an appeal to history. What is found in examination of the races that have used alcohol the longest? Have they undergone a progressive physical degeneracy, as should be expected?
By no means. In this particular respect they seem to have become stronger rather than weaker, as time went on; that is, they have been less and less injured by alcohol in each century, as far as can be told.
Examination of the history of nations which are now comparatively sober, although having access to unlimited quant.i.ties of alcohol, shows that at an earlier period in their history, they were notoriously drunken; and the sobriety of a race seems to be proportioned to the length of time in which it has had experience of alcohol. The Mediterranean peoples, who have had abundance of it from the earliest period recorded, are now relatively temperate. One rarely sees a drunkard among them, although many individuals in them would never think of drinking water or any other non-alcoholic beverage. In the northern nations, where the experience of alcohol has been less prolonged, there is still a good deal of drunkenness, although not so much as formerly. But among nations to whom strong alcohol has only recently been made available--the American Indian, for instance, or the Eskimo--drunkenness is frequent wherever the protecting arm of government does not interfere.
What bearing does this have on the theory of racial poisons?
Surely a consideration of the principle of natural selection will make it clear that alcohol is acting as an instrument of racial purification through the elimination of weak stocks. It is a drastic sort of purification, which one can hardly view with complacency; but the effect, nevertheless, seems clear cut.
To demonstrate the action of natural selection, we must first demonstrate the existence of variations on which it can act. This is not difficult in the character under consideration--namely, the greater or less capacity of individuals to be attracted by alcohol, to an injurious degree.
As G. Archdall Reid has pointed out,[18] men drink for at least three different reasons: (1) to satisfy thirst. This leads to the use of a light wine or a malt liquor. (2) To gratify the palate. This again usually results in the use of drinks of low alcohol content, in which the flavor is the main consideration. (3) Finally, men drink "to induce those peculiar feelings, those peculiar frames of mind" caused by alcohol.
Although the three motives may and often do coexist in the same individual, or may animate him at different periods of life, the fact remains that they are quite distinct. Thirst and taste do not lead to excessive drinking; and there is good evidence that the degree of concentration and the dosage are important factors in the amount of harm alcohol may do to the individual. The concern of evolutionists, therefore, is with the man who is so const.i.tuted that the mental effects of alcohol acting directly on the brain are pleasing, and we must show that there is a congenital variability in this mental quality, among individuals.
Surely an appeal to personal experience will leave little room for doubt on that point. The alcohol question is so hedged about with moral and ethical issues that those who never get drunk, or who perhaps never even "take a drink," are likely to ascribe that line of conduct to superior intelligence and great self-control. As a fact, a dispa.s.sionate a.n.a.lysis of the case will show that why many such do not use alcoholic beverages to excess is because intoxication has no charm for them. He is so const.i.tuted that the action of alcohol on the brain is distasteful rather than pleasing to him. In other cases it is variation in controlling satisfaction of immediate pleasures for later greater good.
Some of the real inebriates have a strong will and a real desire to be sober, but have a different mental make-up, vividly described by William James:[19] "The craving for drink in real dipsomaniacs, or for opium and chloral in those subjugated, is of a strength of which normal persons can have no conception. "Were a keg of rum in one corner of the room, and were a cannon constantly discharging b.a.l.l.s between me and it, I could not refrain from pa.s.sing before that cannon in order to get that rum. If a bottle of brandy stood on one hand, and the pit of h.e.l.l yawned on the other, and I were convinced I should be pushed in as surely as I took one gla.s.s, I could not refrain." Such statements abound in dipsomaniacs" mouths." Between this extreme, and the other of the man who is sickened by a single gla.s.s of beer, there are all intermediates.
Now, given an abundant and accessible supply of alcohol to a race, what happens? Those who are not tempted or have adequate control, do not drink to excess; those who are so const.i.tuted as to crave the effects of alcohol (once they have experienced them), and who lack the ability to deny themselves the immediate pleasure for the sake of a future gain, seek to renew these pleasures of intoxication at every opportunity; and the well attested result is that they are likely to drink themselves to a premature death.
Although it is a fact that the birth-rate in drunkard"s families may be and often is larger than that of the general population,[20] it is none the less a fact that many of the worst drunkards leave no or few offspring. They die of their own excesses at an early age; or their conduct makes them unattractive as mates; or they give so little care to their children that the latter die from neglect, exposure or accident.
As these drunkards would tend to hand down their own inborn peculiarity, or weakness for alcohol, to their children, it must be obvious that their death results in a smaller proportion of such persons in the next generation. In other words, natural selection is at work again here, with alcohol as its agent. By killing off the worst drunkards in each generation, nature provides that the following generation shall contain fewer people who lack the power to resist the attraction of the effect of alcohol, or who have a tendency to use it to such an extent as to injure their minds and bodies. And it must be obvious that the speed and efficacy of this ruthless temperance reform movement are proportionate to the abundance and accessibility of the supply of alcohol. Where the supply is ample and available, there is certain to be a relatively high death-rate among those who find it too attractive, and the average of the race therefore is certain to become stronger in this respect with each generation. Such a conclusion can be abundantly justified by an appeal to the history of the Teutonic nations, the nations around the Mediterranean, the Jews, or any race which has been submitted to the test.
There seems hardly room for dispute on the reality of this phase of natural selection. But there is another way in which the process of strengthening the race against the attraction and effect of alcohol may be going on at the same time. If the drug does actually injure the germ-plasm, and set up a deterioriation, it is obvious that natural selection is given another point at which to work. The more deteriorated would be eliminated in each generation in compet.i.tion with the less deteriorated or normal; and the process of racial purification would then go on the more rapidly. The fact that races long submitted to the action of alcohol have become relatively resistant to it, therefore, does not in itself answer the question of whether alcohol injures the human germ-plasm.
The possible racial effect of alcoholization is, in short, a much more complicated problem than it appears at first sight to be. It involves the action of natural selection in several important ways, and this action might easily mask the direct action of alcohol on the germ-plasm, if there be any measurable direct result.
No longer content with a long perspective historical view, we will scrutinize the direct investigations of the problem which have been made during recent years. These investigations have in many cases been widely advertised to the public, and their conclusions have been so much repeated that they are often taken at their face value, without critical examination.
It must be borne in mind that the solution of the problem depends on finding evidence of degeneracy or impairment in the offspring of persons who have used alcohol, and that this relation might be explainable in one or more of three ways:
(1) It may be that alcoholism is merely a symptom of a degenerate stock.
In this case the children will be defective, not because their parents drank, but because their parents were defective--the parents" drinking being merely one of the symptoms of their defect.
(2) It may be that alcohol directly poisons the germ-plasm, in such a way that parents of sound stock, who drink alcoholic beverages, will have defective offspring.
(3) It may be that the degeneracy observed in the children of drunkards (for of course no one will deny that children of drunkards are frequently defective) is due solely to social and economic causes, or other causes in the environment: that the drunken parents, for instance, do not take adequate care of their children, and that this lack of care leads to the defects of the children.
The latter influence is doubtless one that is nearly always at work, but it is wholly outside the scope of the present inquiry, and we shall therefore ignore it, save as it may appear incidentally. Nor does it require emphasis here; for the disastrous social and economic effects of alcoholism are patent to every observer. We find it most convenient to concentrate our attention first on the second of the questions above enumerated: to ask whether there is any good evidence that the use of alcoholic beverages by men and women really does originate degeneracy in their offspring.
To get such evidence, one must seek an instance that will be crucial, one that will leave no room for other interpretations. One must, therefore, exclude consideration of cases where a mother drank before child birth. It is well-known that alcohol can pa.s.s through the placenta, and that if a prospective mother drinks, the percentage of alcohol in the circulation of the unborn child will very soon be nearly equal to that in her own circulation. It is well established that such a condition is extremely injurious to the child; but it has nothing directly to do with heredity. Therefore we can not accept evidence of the supposed effect of alcohol on the fertilized egg-cell, at any stage in its development, because that is an effect on the individual, not on posterity. And the only means by which we can wholly avoid this fallacy is to give up altogether an attempt to prove our case by citing instances in which the mother was alcoholic. If this is not done, there will always be liability of mistaking an effect of prenatal nutrition for a direct injury to the germ-plasm.
But if we can find cases where the mother was of perfectly sound stock, and non-alcoholic; where the father was of sound stock, but alcoholic; and where the offspring were impaired in ways that can be plausibly attributed to an earlier injury to the germ-plasm by the father"s alcohol; then we have evidence that must weigh heavily with the fair-minded.
An interesting case is the well-known one recorded by Schweighofer, which is summarized as follows: "A normal woman married a normal man and had three sound children. The husband died and the woman married a drunkard and gave birth to three other children; one of these became a drunkard; one had infantilism, while the third was a social degenerate and a drunkard. The first two of these children contracted tuberculosis, which had never before been in the family. The woman married a third time and by this sober husband again produced sound children."