The more enlightened among the Greeks held that slavery was justifiable so long as the masters were Greek and the slaves barbarian, but that otherwise it was contrary to nature. The Jews had, in antiquity, a quite peculiar belief in their own racial superiority; ever since Christianity became the religion of the State Gentiles have had an equally irrational belief in their superiority to Jews. Beliefs of this kind do infinite harm, and it should be, but is not, one of the aims of education to eradicate them.
Source: Bertrand Russell: Ideas That Have Harmed Mankind，1946.
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