You are in a restaurant. It is a smart place, obviously very prosperous, and vast. The clientele is truly international—you can see men and women from every corner of the world. Waiters are going around the tables cheerfully pressing the spécialités de maison on the customers, especially the large numbers of Africans, Asians, and Latin Americans down at the far end of the room, and also, you note, on a newly arrived party from Central and Eastern Europe. But wait. One of the proprietors, an American, seems to be having a serious talk with a group of his fellow countrymen sitting near the door. Quietly, you go to the edge of the group to hear what he is saying.

“It's really great to see you folks,” he says, “and we're so pleased to be able to take care of you again. But first there's something I want to mention tonight: the food is poisonous. It won't necessarily kill you, though the medical folk say that if you keep on eating here, there's a fifty-fifty chance. And even if it doesn't actually kill you, they say it could …