"But you did solve it," Isaac commanded. "Because it was a problem of the calculus, meant to try whether I understood the calculus or not! Can you fathom the impertinence of it!? I was the first man who could ever have solved it, Daniel, and you the second, because you had the calculus from me first-hand. To be hectored thus, by the Baron’s lackeys, three decades after I had invented it—"