by MICHEL FOUCAULT Everyone knows that in France there are few logicians but many historians of science; and that in the 'philosophical establishment' - whether teaching or research oriented - they have occupied a considerable position. But do we know precisely the importance that, in the course of these past fifteen or twenty years, up to the very frontiers of the establishment, a 'work' like that of Georges Canguilhem can have had for those very people who were separ ated from, or challenged, the establishment? Yes, I know, there have been noisier theatres: psychoanalysis, Marxism, linguistics, ethnology. But let us not forget this fact which depends, as you will, on the sociology of French intellectual environments, the functioning of our university institutions or our system of cultural values: in all the political or scientific discussions of these strange sixty years past, the role of the 'philosophers' - I simply mean those who had received their university training in philosophy department- has been important: perhaps too important for the liking of certain people. And, directly or indirectly, all or almost all these philosophers have had to 'come to terms with' the teaching and books of Georges Canguilhem. From this, a paradox: this man, whose work is austere, intentionally and carefully limited to a particular domain in the history of science, which in any case does not pass for a spectacular discipline, has somehow found him self present in discussions where he himself took care never to figure.