The possible world of narrative is the only universe in which we can be absolutely certain about something, and it gives us a very strong sense of truth. The credulous believe that El Dorado and Lemuria exist or existed somewhere or other, and skeptics are convinced that they never existed, but we all know that it is undeniably certain that Superman is Clark Kent and that Dr. Watson was never Nero Wolfe’s right-hand man, while it is equally certain that Anna Karenina died under a train and that she never married Prince Charming.