Unfinished, still a work-in-progress at the time of his death in 1969, Aesthetic Theory is arguably not only Theodor W. Adorno's masterwork, but perhaps the pivotal document of twentieth-century philosophical aesthetics. The book was to be dedicated to Samuel Beckett; and, at one level, the work can be construed as the philosophical articulation of the meaning of artistic modernism, as modernism brought to the level of the concept. Yet even these simple statements cannot be forwarded innocently: that a work of aesthetics stands at or near the center of the thought of Adorno's Marxism has always been cause for consternation and embarrassment; that western Marxism (in the writings of Ernst Bloch, Györky Lukács, Walter Benjamin, and Herbert Marcuse) has been from the outset bound to cultural critique and aesthetic theory can only deepen the puzzle. Some ground-clearing is thus necessary before a real start can be made.