Not long ago, when I was somewhere in my mid-40s, I drove to Cambridge, Massachusetts, from Cape Cod and parked my car in a garage. I was scheduled to give a talk a couple of blocks away and had hoped to arrive earlier. Normally I take a photo of the floor number or the row letter whenever I park in a garage. But worried I was late, I raced out of there without getting a photo and, worse, without consciously registering where I had parked.