The present study analyzes the literary critical thinking formation of the Peruvian writer Mario Vargas Llosa throughout the sixties and seventies. In this period, marked by Cuban revolutionary experience and the international expansion of Latin American narrative, to think literature was also to think about the ways of political-social existence on the continent. Thus, this work is divided into four distinct and relational moments having as main research object the formulation of the theory of the demons of Vargas Llosa systematically developed in his book Gabriel García Márquez: historia de un deicidio (1971). Firstly, an attempt is made to understand Vargas Llosa s understanding of the role of the intellectual and the political-social function of literature in the context of the 1960s, as well as the historicity of his essay on the work of Colombian writer García Márquez. In a second moment, we analyze the content of the theory of demons by establishing dialogues with the thoughts and concepts of other intellectuals, such as Jean-Paul Sartre and Sigmund Freud. Then follows the analysis of the first critical receptions of Vargas Llosa s interpretation of the novelist s vocation and the nature of the literature, understanding that the political positions of the Peruvian writer acquire fundamental relevance in this process. Finally, we discuss the polemic between Ángel Rama and Vargas Llosa in 1972, in which we analyzed through the repertoires and concepts required in the debate the tensions and notions of political-cultural modernization in the discourse of both polemicists.