“Fluminense” Nightmares: Machado de Assis and the Oneiric Sandra Guardini Vasconcelos I know ‘tis but a Dream, yet feel more anguish Than if ‘twere Truth. It has been often so: Must I die under it? Is no one near? Will no one hear these stifled groans and wake me? Samuel Taylor Coleridge In his X-ray of social life and mores in Rio de Janeiro in the second half of the nineteenth century, while depicting everyday events, Machado de Assis (1839–1908) often delved into the inner recesses of the human psyche. Snapshots of perfectly ordinary incidents, of clear-cut, realistic situations though his short stories are, they explore what lies beneath the surface of his characters’ banal and apparently normal existence—their obsessions, monomanias, driving ambitions, unreason, idiosyncrasies, misanthropy—, treading on those chiaroscuro territories of the soul. Not infrequently are his men and women haunted by bad dreams and night- mares, those windows or gateways to the unconscious mind. The most commonplace circumstances may plunge them into the oneiric world, S. G. Vasconcelos (B) University of São Paulo, São Paulo, Brazil e-mail: sgtvasco@usp.br © The Author(s), under exclusive license to Springer Nature Switzerland AG 2025 F. Clemente and G. Colombani (eds.), Nightmares in the Long Nineteenth Century, https://doi.org/10.1007/978-3-031-81164-7_5 113