From Tom Stoppard’s Leopoldstadt, at the Longacre. Photo: Joan Marcus “It’s like a second death” for your name to be forgotten in a family album, a grandmother reflects. Flip back far enough, and who can identify that couple waving from a train except the others who followed them to the grave? One way to look at Leopoldstadt, the latest historical drama by Tom Stoppard, is as a ceremony laying the dead to rest. The genealogical tree that descends on a scrim between the first few scenes is a kind of holy record. Too fleeting to be of much use as...