Many academics like to isolate a piece of the world to study: an important social issue, a central philosophical problem, a key moment in history. They know they're oversimplifying but they do it anyway--it's the only way to make progress, and what's more, their little worlds are often more beautiful than the real one. This paper shares a story of a teacher and a student at the beginning of what turns into a 30-year correspondence and friendship based on a mutual love of calculus.