Metafiction refers to fictional works that explicitly make obvious in some manner that they are fiction, often by explicitly commenting on the fictional/literary devices they are employing. Although it is sometimes argued that these are distinguishing features of modern or postmodern literature, as Wayne Booth pointed out in his Rhetoric of Fiction, the intrusive narrators of traditional works such as Tom Jones and Vanity Fair anticipate metafiction. In theatre, one uses the term metatheatre for the identical case of `breaking the fourth wall`or making the theatrical devices explicit, as in the parabasis of Aristophanes or the plays of Brecht. Godot is less explicitly metatheatrical than many postmodernist plays, but the waiting, being equally true for audiences and characters, can be considered an overarching metatheatrical metaphor.