As always, Nature delights in presenting masterpieces on both sides. She keeps herself serenely above our theories.
Partisans of free sexual exchange between races can quote some examples of wonderfully fine mulattos, much more useful and attractive than their mono-racial ancestors: quadroons of genius such as Dumas and Hugo. They define human alloy as one of those hereditary contaminations which betray themselves in intellectual brilliancy or physical exquisiteness.
Their adversaries retort with any number of cases drawn from colonial history, medical pathology and criminology, by way of proving that the half-breed is an ugly or noxious product, base, limited and undependable, subject to terrible physical ills and incapable of any intellectual accomplishment.
Study of living amalgams has, nevertheless, long since led science to recognise the close cousinship of all humanity, and to envisage humanity as one and indivisible.
What, in fact, really dissociates the animal species is the impossibility of fecundation between them, or at least successive fecundation. An ass and a mare will certainly produce a mule; but the mule itself remains sterile. It is only in libertine Ovid that a swan makes charming Leda pregnant, and that a bull does the same service for another lecherous lady. The centaurs, griffons and sphinxes of classical fable never lived except in the world of poets.
But all men, red, brown, black, olive, hairy or smooth-skinned, perhaps even the great anthropoid ape (he keeps his ideas to himself, but certain stories of women carried off into the jungle are disturbing)—in any case, all men can fecundate any woman, be she as White as a dream. The only exceptions are the consistently sterile.
On the other hand, ever since the earliest stud-farm, people have been conscious of the danger of failing to renew a race, to maintain its strength even by the most paradoxical contributions, such as crossing well-fed, highly-bred subjects with starveling wild strains.
Royal lines, by their degeneracy, have borne witness to the peril of failing to keep in contact with the earth, like Antaeus in the splendid fable, and to return for renewal to the lower orders, to the peasantry, to the poor, those paradoxical possessors of the most wonderful kind of wealth: good health. The triumph of the cosmopolitan race which arose in the United States from the leavings of Europe, as though all America had become one enormous laboratory, has illustrated the thesis that fusion is all to the good.
Here, of course, it was a question only of inter-marriage between Whites: Poles and Latins, Irish and Saxons—all Aryans, with even the Semitic element excluded until recent times.
Meanwhile scientific knowledge about generation, groping during all the centuries from Lucretius’s crooked atoms—which, after all, were not so ridiculous—to Buffon’s animalculae, suddenly acquired a little enlightenment, thanks to patient study of mice and flies.
It was found that a black element, introduced into a white strain, might disappear entirely, and then reappear completely at the fifth or tenth remove. This even led to the deduction of an immutable law of periodicity.
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