How fear has shaped human affairs

One of the bestselling books of all time was about witches. It was not a cheerful romp like the Harry Potter novels. Instead, it was a serious instruction manual, explaining how to identify, capture, torture confessions from—and eventually kill—Satan’s handmaidens. Published in 1486, “Malleus Maleficarum” (“Hammer of Witches”) reputedly sold more copies over the next two centuries than any book bar the Bible.

As Robert Peckham, a fellow at the Royal Historical Society in London, writes in “Fear: An Alternative History of the World”, anxiety about witches sprang from ignorance. Knowing nothing of microbes, people guessed that misfortunes such as disease were caused by magic. Yet their fear could be manipulated for political purposes. Christendom was split in the 16th century, with the pope and various Protestant potentates vying for control. Exterminating witches was a handy way for an earthly ruler to signal which side he was on: God’s, not the Devil’s.