One reason I like writing nonfiction is [that] it's all about the implausible. It's all about Lincoln's kid being there for the first three assassinations. Or Lincoln's son's life being saved by John Wilkes Booth's brother on the train tracks. All these weird coincidences. And bizarre occurrences. With nonfiction it's like, "Holy cow, I can't believe this thing happened!" Whereas fiction seems to me, for it to work, it actually has to seem kind of plausible. Which I would find incredibly difficult.
Sarah Vowell, interviewed by Robert Birnbaum for Identity Theory