The concept of possible worlds (henceforth PW), loosely inspired by Leibniz’philosophy, was developed in the second half of the 20th century by philosophers of the analytic school (Kripke, Lewis, Hintikka [1989], Plantinga [1976], Rescher) as a means to solve problems in formal semantics. These problems are the truth conditions of counterfactual statements (“If a couple hundred more Florida voters had voted for Gore in 2000, the Iraq war would not have happened”) and of sentences modified by modal operators expressing necessity and possibility (hence the close relationship between possible worlds theory and modal logic). Other modal systems have been built around operators expressing what is known as “propositional attitudes” such as beliefs, obligation, and desires. Starting in the mid-70s, PW theory was adapted to the fictional worlds of narrative by the philosopher David Lewis, as well as by a number of literary theorists, including Eco, Pavel, Doležel, and Ryan. Through the questions they ask, PW-inspired approaches have also influenced critics such as McHale, Margolin, Palmer, and Dannenberg. A thorough exposition of the philosophical applications of the notion of possible worlds, as well as a critique of the use of the concept by literary theorists, can be found in Ronen 1994.