Based on historical data and a seminal text never translated into English, we present an original interpretation of Henri Fayol's (1841-1925) administrative theory. This interpretation, which is consistent with the comments that Fayol later presented about his 'General and industrial administration' treatise, brings out his pioneering contribution to management studies. Fayol made the 'unknown' introduced by science into industry the central tenet of modern administration. He foreshadowed major aspects of today's innovation management. More fundamentally, Fayol laid new foundations for the field of management sciences. He drew from the political and philosophical works of the Enlightenment to develop a series of original concepts (in French: prévoyance, perfectionnement, programme, inconnu, corps social) that were difficult to interpret and to translate. We maintain that Fayol's administrative science is a theory of a 'creative/political' rationality that still, today, offers better theoretical and explanatory support for management science than economic and bureaucratic theory.