Among the comparisons and metaphors used in Ferdinand de Saussure’s Cours de linguistique générale the one concerning the game of chess has attracted much exegetical attention. In this article the threefold occurrence of this comparison is analysed, first from a philological point of view (confrontation of the text of the Cours with the students’ notes), and subsequently from an epistemological and a methodological perspective: how are these three uses inserted within the text of the Cours and what is their specific functionality? It is shown that the three uses correspond to a logical approach, moving from the delimitation of the linguistic study of la langue to the definition of units having linguistic “value”.