Writing fiction also means producing a legal language, parallel to that of lawyers. The narrative structure may be related to a social context, but legal speech in the novel is not a mere reflection of it. A crossroads of issues and values, it associates anthropological knowledge, philosophical thinking, life experience. As a mediation between imagination and law sources, literature takes place in the history of legal thinking. Two famous French novels of the 19th century are chosen as illustrations. The writers, Hugo and Zola, who were also active witnesses in the building of a republican society, convey by fictional means a sense of natural law, sustaining the Revolution ideals, evolving to positive law or law science.