extensive academic inquiry. In our view, this work is deeply embedded with philosophical and psychological themes, and thus demands theoretical tools grounded in philosophy for its proper analysis. This article seeks to explore the novel’s content through the theoretical framework of the Self and the Other, as developed by thinkers such as Martin Buber, Carl Jung, and Jacques Lacan.The central research question is: What is the core philosophical theme of the novel Vendredi ou les Limbes du Pacifique, and how does the theory of the Self and the Other enhance our understanding of it? The methodology employed is both descriptive and analytical. Drawing on the relationship between Robinson and Friday, we argue that for Tournier, human identity and essence are fundamentally dependent on the presence of the Other. Ontologically speaking, it is through the Other that the human subject comes to recognize and realize their own humanity. Martin Buber’s concept of the I–Thou relationship offers a compelling theoretical model for interpreting the dynamic between Robinson and Friday.