A research on similar lines by S. R. Steinmetz[69] in Holland shows that the average number of children in the lowest class families is 5.44. People in industry or small trade, skilled mechanics and professors of theology have five children to the family; in other classes the number is as follows:
| Artists | 4.30 |
| Well-to-do Commercial Classes | 4.27 |
| High Officials | 4.00 |
| University Professors (excluding theological) | 3.50 |
| 23 Scholars and Artists of the first rank | 2.60 |
It is not hard to see that the next generation in Holland is likely to have proportionately fewer gifted individuals than has the present one.
Fortunately, it is very probable that the differential birth-rate is not of such ominous import in rural districts as it is in cities, although some of the tribes of degenerates which live in the country show birth-rates of four to six children per wife.[70] But in the more highly civilized nations now, something like a half of the population lives in urban districts, and the startling extent to which these urban populations breed from the bottom involves a disastrous change in the balance of population within a few generations, unless it is in some way checked.
Just how great the change may be, statistically, has been emphasized by Karl Pearson, who points out that "50% of the married population provide 75% of the next generation," owing to the number of deaths before maturity, the number of celibates and the number of childless marriages. "The same rule may be expressed in another way: 50% of the next generation is produced by 25% of the married population." At this rate in a few generations the less efficient and socially valuable, with their large families, will overwhelm the more efficient and socially valuable, and their small families.
Fecundal selection is at work to-day on a large scale, changing the character of the population, and from a eugenic point of view changing it for the worse. Fortunately, it is not impossible to arrest this change.
But, it may be objected, is not this change merely "the survival of the fittest?" In a sense, yes; and it is necessary that the more intelligent classes should make themselves "fitter" to survive, by a change of attitude toward reproduction. But the dying-out of the intellectually superior part of the population is a pathological condition, not a part of normal evolution; for barring artificial interference with the birth-rate, fertility has been found to go hand in hand with general superiority. This demonstration is due to F. A. Woods' study[71] of 608 members of the royal families of Europe, among whom, for reasons of state, large families are desired, and among whom there has probably been little restraint on the birth-rate. Averaging the ratings of his individuals from grade 1, the mentally and physically very inferior, to grade 10, the mentally and physically very superior, he found that the number of children produced and brought to maturity increased in a fairly direct ratio. His figures are as follows:
| Both Sexes (Averaged) | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Grades for virtues | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
| Average number of adult children. | 1.66 | 2.86 | 2.99 | 2.41 | 3.44 | 3.49 | 3.05 | 3.03 | 3.93 | 3.83 |
Investigations of Karl Pearson and Alexander Graham Bell[72] show that fecundity and longevity are associated. It follows that the mentally and morally superior, who are the most fecund, are also the longest-lived; and as this longevity is largely due to inheritance it follows that, under natural conditions, the standard of the stratum of society under consideration would gradually rise, in respect to longevity, in each generation.
Such is probably one of the methods by which the human race has gradually increased its level of desirable characters in each generation. The desirable characters were associated with each other, and also with fecundity. The desirable characters are still associated with each other, but their association with fecundity is now negative. It is in this change that eugenics finds justification for its existence as a propaganda. Its object is to restore the positive correlation between desirable characters and fecundity, on which the progressive evolution of the race depends.