[The workings of a Darwinist brain: Guedes Cabral and the evolutionism ofFunções do cérebro(1876)].

The book Funções do cérebro (Workings of the brain), by physician Domingos Guedes Cabral, is recognized as one of the first Brazilian works to defend Darwinist theories. In light of the need for more studies on the reception of evolutionism in Brazil, the article investigates this book in an effort to reveal how Guedes Cabral used evolutionism in his argumentation and to reveal the purpose of his arguments within a historical context. Findings indicate that Guedes Cabral relied on evolutionism as part of both an ideological project and an incipient eugenic theory, later developed in the early twentieth century.