Using as a basis for the study the manuscripts of the Société royale de médecine dealing with diseases of craftsmen in the 18th century, it is interesting to pick out in the language of both the doctors and the work inspectors of the time the ambiguous articulations which establish a link between the needs for order in the city, for efficient work and for an enlightened humanism. The style of speech, which begins to take form as early as 1768, already contains all of the elements which underly the dominant 19th-century ideology concerning the worker's body, his mores, his production capacity and what his family life should be. The 18th-century humanist already dreamed of well-lighted work-shops; everything that is opaque was easily blamed on the worker; he must therefore be educated in order to be saved from himself