Are we there yet?” my son Andy cries just as we are pulling out of the driveway. “Are we there yet?’ when we drive up to the McDonald’s take-away window. “Are we there yet?” when we stop at a traffic light. No, not yet. Unable to grasp any estimate I might give him (is an hour short? is a day long?), he fusses, then falls asleep, only to wake up surprised upon our arrival.