© 2018 Universidad de Murcia Servicio de Publicaciones. All right reserved. The article starts with an overview of the idea of fraternity developed by the republican French thinkers around 1848. Fraternity was seen as the main idea to fight individualism and set up a new social order. But fraternity has been rapidly ignored by contemporary thought, contrary to what has happened to the two other mottos of French Revolution -liberty and equality. We are wondering now weather it is necessary to recover the concept of fraternity and in what sense it should be understood. Is it a virtue in the aristotelian sense of the word? It seems to the author the more understandable way to consider fraternity -a virtue or moral obligation essential for social cooperation or justice.