Imagine yourself for a moment in Western Nigeria on a moonlit evening. The day's work has been done, and friends and neighbors have gathered. Suddenly one among the group turns to an older man sitting at the edge of the piazza. "Tell us a story," he begs. And he knows what he is asking. Many in the group can tell stories and very well indeed, for storytelling has been a tradition in Nigeria for hundreds of years. The old man rises and usually begins,...