O Ateneu is a novel by Brazilian writer Raul Pompeia, considered the only example of an impressionist novel in Brazilian literature. First published in 1888, the book tells the story of Sérgio, a boy who is sent to a prestigious boarding school in Rio de Janeiro. Run by the authoritarian Aristarco, the school maintains strict rules and principles of the aristocracy of the time. The work critiques the Brazilian society of the late 19th century, using the Ateneu as a metaphor, its reflection, a place where the strongest always prevails.