The simple lesson it took me a half century to understand

In a memorable joke, a snail slithers into a bank, robs it, and slithers out the door and down the sidewalk to freedom. Minutes later the police arrive and interview the witness, a turtle next in the teller’s line, asking the languid leatherback what he saw. "I don’t know," the terrapin replies in exasperation. "It all happened so fast."

The joke’s larger truth is a universal one: Perspective matters, with respect not only to speed but also to time. I know this because every day I feel more...