one roof on the planet. And as he walked or sat -- near a play area, a musical fountain, petting zoo, this month a Santa throne ... the man often felt a domestic snugness. Like being a guest in a shiny estate where every distant relative and friend, and friend of friend, was gathered for a holiday. At other times he would feel a sudden despair-the fluorescence on flesh and mannequins, the relentless piped music, the plate glass -- all a mere scrim about to tear and return him to the abyss that had followed his wife's death. Then he would obey the therapist's and his daughters' long-distance counsel to do something: physically move and speak. He would order a decaf and kid the counter-teenager about her paper cap. He would discuss a swarm of blue-haired shoppers with a retired farmer in a seed cap ... question a security guard rubbing socked feet on break. The abyss would fade; the