On vaccines, some people would rather be dead than wrong

Yes, your opponents really do believe those crazy things

During the grimmest days of the First Crusade in 1098, the western Christians found themselves besieged by the Turks in Antioch. They had travelled more than a thousand miles from France, and countless fellow believers had died in the almost impossible trek across the known world; now running out of food and water, they were tired, hungry and desperate.

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