The paper presents a novel approach towards the analysis of a classic Spanish 20th century novel, Five Hours with Mario by Miguel Delibes. The author of the paper proposes two interpretative frameworks, of which The Moral Foundations Theory developed recently by Jonathan Haidt is the main one, and Karl Popper’s concept of the open and closed society, a complementary one. The interdisciplinary reading of Delibes’ masterpiece should help students and scholars revive and update their relationship to this worthwhile piece of fiction, as well as provide them with theoretical tools for an in-depth understanding of the differences between the moral outlook of liberals and conservatives, tools applicable both on the level of fiction, as well as in reality.