 David Lewis provided the classic discussion of this issue in his “Truth in Fiction” (first published in 1978, reprinted with postscripts in 1983). His approach has two core ideas. The first is that we should adopt a pretense view of fiction. A fiction is a story told by a particular person on a particular occasion, and to tell a story is typically to pretend that one is relating an account of things that really did happen. The second core idea is the one mentioned above: stories are related against a background of (known) facts and beliefs, thereby ensuring that there is more to truth in fiction than is stated in stories. The novelty of Lewis’s approach is the way he understands this background and its impact in terms of the machinery of possible worlds and the semantics of counterfactuals. To put the point in technical jargon, Lewis treats in-the-fiction operators as special intensional operators.