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"Characters inside fictional worlds are also capable of sustaining propositional attitudes and projecting possible worlds. Eco calls these possible-worlds-within-possible-worlds subworlds; Pavel prefers the term narrative domains. It is the tension and disparity among various characters' subworlds, and between their subworlds and the fictional "real" world, that formed the basis of modernist and, before that, realist epistemological poetics."
— Brian McHale, Postmodernist Fiction (info)