Michael Hardt's Gilles Deleuze: An Apprenticeship in Philosophy was a formative book for me in graduate school. Formative in the sense that it shaped my reading of Deleuze, but also in that it shaped my idea of what a book on a philosopher could or should do. What impressed me about Michael's book way back then is that he did the necessary work to excavate some of the concepts underlying Deleuze's books, not just Spinoza, Nietzsche and Bergson, but also Dun Scotus and Hegel, while at the same time recognizing that Deleuze's work is not pointed towards the past, to its history, but to debates with such philosophers as Althusser and with such movements such as autonomy. It is rare to find a book that is equally comfortable discussing scholastics and Nanni Balestrini.
