Our fellow historian Peter Brown reports that according to a memoir written, sometime around 1900 by a contemporary of Benedetto Croce, the eminent Italian philosopher, Croce challenged a colleague to a duel over an issue of metaphysics. What a startling report that makes you eager to turn the page—as in a John Gresham volume—in order to find out what happened. But nothing more is said in the book, compelling the conclusion that for the author, this was routine, unimportant, and even normal for professors to challenge each other to deadly duels. He must have thought that no explanation was necessary. And so a single sentence stands alone, tantalizing, unexplained—for contemporaries commonplace; for posterity altogether startling. What a splendid introduction to how to see the past offered us by Peter Brown!