This article focuses on two concepts, irony and idiocy, as they appear in the works of Plato and Dostoevsky. In Plato's case, the article describes how irony is thematized in a rhetorical mode and also deployed as a dialectical method, creating dramatic tension that produces additional layers of significance. In Dostoevsky's case, it addresses his thematization of irony and its deployment as a dialectical method to develop idiocy as a framing concept for the novel. Setting aside general philosophical issues relating to Plato's use of literary representation, as well as broader thematic implications of idiocy in Dostoevsky, the article focuses on a thread passing from Plato to Dostoevsky, through the concepts of irony to idiocy, and suggests that just as Plato's dialogues have a representational layer in which their text points to a layer of dramatic significance, so Dostoevsky's novel has a conceptual layer pointing to philosophical significance. This philosophical significance, embedded in dialectical irony as a literary method, does not necessarily encapsulate any specific idea. Yet it does indicate that, beyond the representation of the novel's characters as tragic figures, there lies a potential for understanding the book, in its entirety, as a tale of cautionary wisdom.