Abstract“Prosaism”, in its first meaning in French, refers to a defect in poetic discourse, too many expressions and ways of writing which are those of prose. Prosaism would in some way be a relaxation of poetic effort. It follows that if we know well what this effort would consist of (inspiration, elevation, elegance, etc.), prosaic relaxation only receives negative characteristics (without relief, without brilliance, without ideal, etc.).Prosaism is positive on at least one point: it would manifest a return to reality, and to the world of common sense, which is evidenced by its “sarcastic” or provocative uses. But the presupposition would be in this case that the poetic effort would consist of moving away from reality, or even ignoring it: these respective conceptions of reality and of poetic effort are stereotypical and reductive.Merleau-Ponty, in The Prose of the World, offers us another path: he strives to establish the conditions so that prose is able to create or reconfigure a world. The key to the transformation of “prose” into “great prose” is his theory of expression, the encounter between language and the own world of the enunciator. It is then possible, beyond the distinction between genres of discourse, to precisely describe the different ways of being-in-the-world of enunciations, and to ask whether these are “regional ontologies” or of “forms of living”.