Drawing on fresh readings of Marxist and post-modern thought, renowned German cultural critic Diedrich Diederichsen compares the abstract and climbing values of artworks with the plunging value of music¿a traditionally immaterial art¿in order to formulate a broad reflection on the current ¿crisis of value in the arts.¿ In his essay, Diedrich Diederichsen applies the Marxist theory of surplus value (Mehrwert) to rationalize value formation in contemporary art, in sly defiance of the invocation of art¿s "extra special" quality (which, ironically, is also implied in the colloquial use of Mehrwert) as a substitute for serious discussion on the subject. He then goes on to elaborate on art as a "commodity form" and on the notion of "aura" that applies to this. Continuing to operate in contradistinction to received wisdom, he accounts for aura regardless of the specific material constitution and uniqueness of an art object, yet (perhaps paradoxically) preserves the notion of this object as "index". Here too contemporary art¿s condition of reproducibility acquires crucial nuance. The final chapter compares contemporary art to other cultural industries, such as music and film, which are firmly under the sway of digital reproductive economies yet, unlike contemporary art, are experiencing diminishing possibilities for the creation of surplus value. Diedrich Diederichsen¿s text offers provocative resolutions to the question of Mehrwert in art that are ripe for debate. Especially perhaps, in his final paragraphs, where the "special case" of contemporary art is dealt a set of disturbing predictions about the shifting cultural values that attend the economic ones. On (Surplus) Value in Art constitutes the first book of the new series Reflections, co-published by Witte de With. Each edition, consisting of a specially commissioned essay, engages a leading thinker in re-considering one key question that defines contemporary culture.