Long ago, Charlie laid out his strongest ambition: “All I want to know is where I’m going to die, so I’ll never go there.” That bit of wisdom was inspired by Jacobi, the great Prussian mathematician, who counseled “Invert, always invert” as an aid to solving difficult problems. (I can report as well that this inversion approach works on a less lofty level: Sing a country song in reverse, and you will quickly recover your car, house and wife.)

