This dissertation analyzes the ways in which monstrosity is articulated in fantastic literature, a genre or mode that is inherently devoted to the challenge of representing the unrepresentable. Through the readings of a number of nineteenth-century texts and the analysis of the fiction of two twentieth-century writers (H. P. Lovecraft and Tommaso Landolfi), I show how the intersection of the monstrous theme with the fantastic literary mode forces us to consider how a third term, that of language, intervenes in many guises in the negotiation of the relationship between humanity and monstrosity. I argue that fantastic texts engage with monstrosity as a linguistic problem, using it to explore the limits of discourse and constructing through it a specific language for the indescribable. The monster is framed as a bizarre, uninterpretable sign, whose disruptive presence in the text hints towards a critique of overconfident rational constructions of 'reality' and the self.

The dissertation is divided into three main sections. The first reconstructs the critical debate surrounding fantastic literature -- a decades-long effort of definition modeling the same tension staged by the literary fantastic; the second offers a focused reading of three short stories from the second half of the nineteenth century ("What Was It?," 1859, by Fitz-James O'Brien, the second version of "Le Horla," 1887, by Guy de Maupassant, and "The Damned Thing," 1893, by Ambrose Bierce) in light of the organizing principle of apophasis; the last section investigates the notion of monstrous language in the fiction of H. P. Lovecraft and Tommaso Landolfi.