The aim of this paper is to analyze Prieto's reading of Éric Buyssens' seminal work on semiology, Les langages et le discours, Essai de linguistique fonctionnelle dans le cadre de la sémiologie. The analysis is made from two perspectives: a historical perspective and a theoretical perspective. The historical perspective presents the context, regarding Prieto's academic work, within which Prieto read Buyssens, for this we take into consideration the papers Prieto published in second half of the 50's and the research reports from 1962 to 1965 that are held in the Prieto archives at the Universidad Nacional de Córdoba. The theoretical perspective is mainly grounded on the hypothesis that Prieto made a “cognitive reading” of Buyssens' claims. The analysis is divided according to three thematic areas: (a) the treatment of “abstraction” in Buyssens and in Prieto, (b) the problem of the delimitation of functional units as a cognitive problem, and (c) the distinction between communication versus indication.