ABSTRACT
According to modal logic (better known among literary scholars as possible worlds theory), a world is possible with respect to another world when it is linked to this world by a so-called accessibility relation (Kripke 1963). Since this relation can be conceived in many different ways, possibility and impossibility are relative concepts. Possibility could denote what may happen in the future, according to the laws of nature: for instance, the tower of Pisa could collapse some day and kill scores of tourists. In a more remote type of possible world, the laws of physics and biology no longer hold, so that princes can be turned into toads and vice-versa. These worlds, which can be called unnatural, are widely represented in literature, as popular genres such as fairy tales, medieval fantasy and science fiction demonstrate. Yet realistic texts that respect the laws of nature and fantastic texts that extend the possible beyond the natural do not exhaust the set of all possible texts: an important form of experimental literature creates worlds that cannot satisfy even the most liberal interpretation of possibility. Such works transgress the logical laws of non-contradiction (not p and ~p) and excluded middle (either p or ~p).
