The lost cities I shall talk about are of two kinds. The first kind are lost to those who are obsessed with an inaccessible city and, yet, weighed down by the awareness that their fading, half-lost memories might die with them, that the city of the mind may not survive except in shared fantasies—in literature or arts. The city they have kept alive by sheer power of will might be doomed. That sense of transience imparts a touch of bittersweet sadness to the imagined city. Lost cities can be lost in many ways. Jerusalem is lost in one way, Pompeii...