The poet Stéphane Mallarmé was always a key figure for Marcel Duchamp and a major ally in the quest to invent the art of the future. In this essay, Thierry Davila essay focuses in particular on three aspects of this relationship: the window (translucency), an object celebrated by the poet and the artist; the life of fluids (smoke, wind); and nothingness. Through these themes, the text also proposes an interpretation of the readymade and the infra-thin.