A meticulous and authoritative biography of the influential French philosopher and historian, by an editor at Le Nouvel Observateur who was closely acquainted with Foucault during his later years. Foucault (1926-84) is known in this country mainly as one of the prime exemplars of structuralism, the radical school of thought developed in the late 60's and 70's to question the foundations of many social and philosophical systems. In reality, as Eribon makes clear, Foucault was more of an intellectual historian than a philosopher, and achieved his greatest successes when attempting to set forth the ``archaeology'' of a concept or idea. This is what he did in Madness and Civilization, which traced the development of Western notions of sanity and reason as reflected in social attitudes towards madness. His monumental History of Sexuality, left unfinished at his death, was to provide a similar blueprint for the modern understanding of eroticism. Eribon's exposition is readable and clear, and makes good use of the many interviews he held with Foucault during his lifetime, as well as his meetings with Foucault's colleagues and friends. The picture that emerges is of someone at once distant and complex: Foucault hated easy characterizations and refused to ``take sides'' when it came to politics or philosophy. His early dalliance with Marxism quickly gave way in the late 50's, and his later conservatism evaporated as soon as he won his post at the College de France (where, during the 70's and 80's, he became known as one of the most active leftists in the country). Solitary and rather reclusive despite his wide circle of friends, Foucault's public life was largely restricted to his professional writings, and it is to Eribon's credit that he concentrates mainly on these, since they provide the truest picture of Foucault available. Superbly written and carefully documented: Eribon has managed to provide a scholarly exegesis of Foucault that will also serve as a good introduction for the lay reader.