great figure of the French sociology of the first half in the 20th century, Maurice Halbwachs has realized a work of a great richness, which goes from the study of the social morphology to that of the collective psychology and which analyse matters such as consumption, social classes, memory of the social groups, suicide, urban life, religion or demography. It consists also in numerous methodological writings dedicated to the quantification in social sciences and reveals to the French public a few (...) foreign essential authors, like Werner Sombart, thorstein Veblen, Max Weber, robert Park, Ernest Burgess or John M. Keynes. this article presents several fundamental concepts of Maurice Halbwachs’s work between which appear those of social morphology, social class and class conscience. (shrink)