It is an accepted fact at the beginning of the nineteenth century that writers have been influenced by the conditions of their social life. But another sociology of literature, inverse but complementary to the first, was developed, based on the assumption that literature had an influence on the social conditions of existence - both writers and readers And, through their channels, of the whole "society". From Madame de Stael and throughout the nineteenth century, this study follows the deployment of this new sociology which took to heart to explore the reciprocal of the formula bonaldienne (literature as "expression of society") If we think then that literature has a social influence, it is because during the Romantic period there was a major revolution affecting the sphere of influence of the literature: its action is not exerted Not only in the world of ideas, but in the sphere of practical life. This increased influence of literature on manners was accentuated by the romantic theories which insisted that literature should cease to be a bookish matter in order to be in direct contact with life, and to make writers not only masters of thought, but also Of the masters to live. This article then considers some of the consequences of this formatting, which, because of the new media order, contributes to the definition of stereotyped lifestyles ("poet life", "artist life", "life" Of bohemia "). But this formatting also influences the writers themselves, led to adopt habits in accordance with their literary choices: which means that the main auctorial scenarios have engendered ready-to-live. The next generation, that of Flaubert, denounced such a link of necessity between literature and life, characteristic of romanticism rejected. But, paradoxically, the Flaubertian revolution amounts to making literature continue to govern the lives of writers, who are now called upon to live a non-life in conformity with the new literary religion.