different races. If the science of eugenics deserves any practical application at all, it should insist upon a careful study of the every-day violation of its cardinal principle by a whole race who persistently refuse to practise the very doctrine which is essential to the preservation of a sound and healthy mentality. I refer to the Jews.
In order to further elucidate the subject and to make good this rather bold assertion, I propose to prove the following propositions: First, the Jews are a highly inbred and psychopathically inclined race. Second, the prevalence of mental affections among them is almost entirely due to heredity.
That the Jews are as a matter of fact racially pure is a statement that must not be taken absolutely in a literal sense. All races have received admixtures of some outside blood, but it is undoubtedly true that, since the time of the prophet Ezra and his campaign for racial purity which was begun at the time of the return from the Babylonian captivity, 536 years before Christ, the central stem of Judah has remained practically free from admixture with other races. Any student of the old testament can easily substantiate the statement that violations of the law against marriage with the heathen races, by which they were surrounded, were, from that time on, most summarily punished. The feeling against such procedure grew in intensity until, at the time of the fight for the maintenance of Jewish independence under the Maccabees, it had reached such a degree of fervor that rabbinical decrees forbade friendly social intercourse with the Gentile on any pretext whatever. There is no doubt but that the Jews inter-married and inbred among themselves on an ever increasing scale clear up to the time of the fall of Jerusalem.
After the Dispersion, there is some difference of opinion as to the degree with which they maintained the racial purity which they had been over 600 years in establishing. The weight of evidence, however, is all in favor of the view that they did not abandon the time-honored doctrine of racial solidarity. During Roman times and the dispersion throughout the Mediterranean littoral, the rabbinical decrees were still vindictive in their treatment of the subject. To such extreme lengths did they go, that the Goy or Gentile party to the contract was regarded as having no right at all, but was considered like the slave, as having a status that rendered him incapable of connubium with the Jews.
Those anthropologists who cite the fact that there were a great many converts to Judaism immediately after the fall of Jerusalem, and that the Jews thus received a great deal of Roman blood into their veins, overlook the fact that these converts were the very ones from whom the Christians in turn drew the majority of their converts. Thus the Judaized Romans were almost immediately lost to Judaism.
- Ephraim Feldman, "Intermarriage, Historically Considered," p. 19.