The monarchs of seventeenth-century Europe put a surprisingly high priority on the abolition of dueling, seeing its eradication as an important step from barbarism toward a rational state monopoly on justice. But it was one thing to ban dueling and another to stop it. Duelists continued to kill each other with swords or pistols in significant numbers deep into the nineteenth century. In 1883 Maupassant called dueling "the last of our unreasonable...