International audienceGabriel Tarde, the judge of Sarlat, attributes to statistics a central place in his sociology, as shown by his studies of criminal statistics. He develops an original and clear notion of the role of statistics which he regards as the prefered instrument that allows us to describe not the state but the evolution of social phenomena. The aim of the article is to estimate the relevance and the limits of this dynamic conception of statistics, by showing how it is closely linked, in Tarde's studies, to his philosophical and sociological doctrine.Gabriel Tarde, le juge de Sarlat, attribue à la statistique une place centrale dans sa sociologie, comme le montrent ses études de statistique criminelle. Il y développe une concept...