Anglo-Saxon prison sociology presents the world of prisons as a “subculture” and inmates as a “specific community”, with its social roles and specific values, as opposed to common social values. Prison ethnographic research which takes into account the pragmatic dimension of speach shows on the contrary that those in prison for longer periods, who are deprived of outside family and social distinctions and have to struggle against prison promiscuity construct moral figures, on the basis of conventional values, who represent ideal individuals. These figures are used as reference points to create differentiated groups, on the basis of a commun simplified classification system, which make social relations possible. They also allow prisoners to present themselves as moral individuals.