The belief in witchcraft, until about the middle of the seventeenth century, afforded a most satisfying outlet for the delicious emotion of self-righteous cruelty. There was Biblical warrant for the belief, since the Bible says: 'Thou shalt not suffer a witch to live.' ... In modem times, these same emotions find an outlet in fear of foreign nations, an outlet which, it must be confessed, requires not much in the way of superstitious support.
Source: Bertrand Russell: Ideas That Have Harmed Mankind，1946.
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