Whether they are Americans, Brits, or a stubborn and suicidally moral Dutchman, Norman Rush's whites are not sure why they are in Botswana. Their uncertainty makes them do odd things. Driven half-mad by the barking of his neighbor's dogs, Carl dips timidly into native witchcraft — only to jump back out at the worst possible moment. Ione briskly pursues a career as a "seducer" ("A seductress was...