As in other works, in "Discourse in the Novel," Bakhtin distinguishes the novel from other genres, such as poetry, through its multiplicity of voices. Novels are not univocal but dialogic: different peoples of different classes, genders, and outlooks engage in dialogue and debate. The novel, therefore, contains conflicting points of view for the reader to consider and explore. With various voices in debate, the novel inevitably becomes political.
Bakhtin called these different, competing voices in a novel heteroglossia, and he said we derive meaning from novels by considering and evaluating these divergent voices or utterances. Heteroglossia includes the concept that characters' speech acts includes point-of-view and ideology: therefore each character can use the same words, but they can mean different things to each. "Each character's speech possesses its own belief system," he wrote. He also said that we can't simply isolate one voice in a novel and base our interpretation on its utterances alone. To understand a novel, we must take it as a whole.
Bakhtin argues that characters in a novel speak ideologically, and they express their ideology through their actions, what they say, and how they say it. Even novels that claim an apolitical stance are political. For example, he points to Oscar Wilde's Picture of Dorian Gray, as well as other works by aesthetes (artists who believed in "art for art's sake" and not for any political purpose) and writes:
Thus even an aesthete, working on a novel, becomes an ideologue who must defend and try out his ideological positions.
Bakhtin's idea of the novel as consisting not of unity and uniformity and an apolitical space but filled with multiplicity and political meaning became popular in the early 1980's world of post-structuralism and deconstruction, when traditional ideas about interpretation were being heavily contested.