An examination of the relation between war and politics, by one of the twentieth century's most influential thinkers From 1971 until 1984 at the Collège de France, Michel Foucault gave a series of lectures ranging freely and conversationally over the range of his research. In Society Must Be Defended , Foucault deals with the emergence in the early seventeenth century of a new understanding of war as the permanent basis of all institutions of power, a hidden presence within society that could be deciphered by an historical analysis. Tracing this development, Foucault outlines the genealogy of power and knowledge that had become his dominant concern.