L. Cambrezy — Environment and Population Density : Resorting to History. In the arduous study of the relationship between Nature and Society, environment must needs be considered as a global whole, since it is perceived and used as such by its occupants. This affirmation is a triviality, y et the implementation of an approach fitting this objective is confronted with a permanent contradiction between an analysis which has to conform strictly to the traditional classification of sciences, on the one hand, and, on the other hand, the imperative demand of a quest for relations and interactions which is hardly reconcilable with that division of knowledge. Problems have to be set down under a systemic approach, in order to account for the actual...