Humboldt and Darwin held the same opinion. Hilaire Belloc in "The French Revolution" notes regarding Marat
Some say. . . that a mixture of racial types produced in him a perpetual physical disturbance: his face was certainly distorted and ill-balanced (p. 78).
Schultz claims to have noted an intrinsic deterioration in GentileJew crosses. Le Bon expresses himself as follows:
To cross two peoples is to change simultaneously both their physical constitution and their mental constitution. . . the first effect of interbreeding between different races is to destroy the soul of the race, and by their soul we mean that congeries of common ideas and sentiments which make the strength of people, and without which there is no such thing as a nation or a fatherland . . . a people may sustain many losses, may be overtaken by many catastrophes, and yet recover from the ordeal, but it has lost everything and is past recovery, when it has lost its soul (pp. 53-55).
Le Bon explains this supposed necessary degeneration in half-breeds as due to the "influence of contrary heredities" which "saps their morality and character." We shall return to Le Bon's idea of a loss of "soul" as consequent of inter-racial crosses.
This same idea of necessary degeneracy in crossbreeds is the main motive of much opposition to foreign immigration. We shall see that this is the very least element of danger; in fact, it may be a real panacea to other actual evils of immigration, otherwise (i. e., without neutralization through cross-breeding) a serious menace. Note here the superb products of the English, German, Dutch, French and Spanish crosses of late and post-colonial days. The superiority of especially the English-German crosses, very generally noted, finds its reason in the initial superiority of the crossing stocks. And this is the secret of the entire matter. Offspring take after their parents, whether these be of the same or different race. The production of the Boer race, one of well-marked physical and mental characteristics, notwithstanding that it is of mongrel immigration, Dutch, French, and in some degree, British, is sufficient disproof of inherent hurt in inter-racial crosses. The more progressive of "white" nations have been produced by European interbreedings, for example, the English and the Bulgars. Furthermore, Davenport reminds us of probably even Ethiopian contributions to our European stock, "when we stop to consider the slaves, not only white and yellow, but also brown and black, that were brought to Rome, became free there and contributed elements to the population of Italy and to all Europe." Indeed, this may well have been a partial source of the pigment of European brunets.
Thoroughbred parents produce similar progeny. Inferior or degenerate parents have only defective children. In proof of which the following: Probably the most brilliant student I have ever known is the son of a high-class Chinese woman by an American missionary. There is probably as great a difference, from a general anatomical viewpoint,
