This selection of some forty texts written mainly in the 20th century is proposed by the active researchers associated with Problemata. It makes up the first shelf of a library. It is not an anthology. On the one hand, it assumes the notion of heteroclite as defined by Foucault. For another, it resists this power of heterogeneity and diffraction and crosses economy, cultural history, history of art or history of techniques. It brings together the style of the selected pieces of teaching, the genre of the “mélange” which are a classical homage or the more contemporary one of the playlist. In so doing, it proposes itself as a reading cabinet where chance encounters and masterly orientation are articulated.