The job of an art critic is to take perpetual inventory, constantly revising her ideas about the direction of contemporary art and the significance of the work she writes about. In these essays, which span three decades of assessment and reassessment, Rosalind Krauss considers what she has come to call the "post-medium condition" -- the abandonment by contemporary art of the modernist emphasis on the medium as the source of artistic significance. Jean-Francois Lyotard argued that the postmodern condition is characterized by the end of a "master narrative," and Krauss sees in the...