Ernst Cramer, the late, great editor-in-chief of the German daily Die Welt, once recounted how as a college student in America in the midwest, just after World War II, he questioned in a math class whether the textbook was not mistaken in a particular instance. The lecturer reflexively, and rather sternly, dismissed the possibility. Several months later, Cramer was working on a farm during summer vacation when he looked up to see his professor jogging across the field from a parked car in the distance. “Cramer,” a repentant voice yelled, “you were right – the book was wrong and they’ve changed that section!”