When our twins were quite young — infants really — I remember a scene that played out on our living room floor. My son, ever the gregarious and energetic one had managed one afternoon to yank the leg off our old studio piano. He was sitting there gleefully pounding it on the carpet while his twin sister egged him on, shouting, "Go, Aaron, go!" In defense of my daughter, it needs to be said that the boy didn't require any encouragement. Furthermore, it didn't occur to either their mother or myself that we needed to lay down the law about tearing the leg off the piano. Nonetheless, there they were, in the Garden of Eden, reaching for the fruit.

Another time we had stayed up with the children watching the ice skating championships. It was fun seeing the artistry and beauty of the skating, a…