The opening of a particle accelerator at Brookhaven National Laboratory in 2000 inspired fears that high-speed collisions might launch a chain reaction that could turn the earth into a hyperdense sphere about one hundred meters across. A risk calculation determined this to be unlikely; if the collider were to run for ten years, the chance was no greater than 1 in 50 million. “The word unlikely, however many times it is repeated,” wrote concerned scientists, “just isn’t enough to assuage our fears of this total disaster.”

Plutarch related that news of the Athenians’ brutal defeat at Syracuse during the Peloponnesian Wars first came from a stranger who told the story at a barbershop “as if the Athenians already knew all about it.” When the barber spread the news, city leaders branded him a liar and an agitator. He was “fastened to the wheel and racked a long time.” Official messengers later came with the “actual facts of the whole disaster,” and the barber was released.

Accounts varied of the Great Famine of 1315–22, during which more than 10 percent of Europe’s population died. In Flanders: “Parents killed their children and children killed parents, and the bodies of executed criminals were eagerly snatched from the gallows.” In France: “There was no wine in the whole kingdom.”

According to sixth-century-bc Greek poet Hipponax of Colophon, in times of drought, famine, or plague an ugly or deformed person was chosen by the community to be pharmakós, or scapegoat. After being fed figs, barley cake, and cheese, he would be struck on the genitals with the bulbs and twigs of wild plants, led on a procession accompanied by flute, and burned on a pyre. His ashes were thrown into the sea. It is believed that Hipponax, whom Pliny the Elder once called “notoriously ugly,” may have been exaggerating the ritual.

Astrologers of the Ayyubid Empire predicted in 1186 that the world would end September 16 of that year; a dust storm, stirred up by planetary alignment, would scour the earth of life. Sultan Saladin criticized the “feeble minds” of believers and planned an open-air, candlelit party for that evening. “We never saw a night as calm as that,” an attendee later remarked.