Despite accusations of irresponsibility and negativity, Jacques Derrida's deconstruction has had an immense influence on contemporary social, political and cultural critique. 'Evolving negativity' offers a preliminary explanation of this influence by tracing the philosophical 'family tree' that links deconstruction to German Critical Theory via the Frankfurt School. The paper explores the origins of a certain dynamic and productive notion of negativity in Hegel's dialectic and describes its 'evolution' in the works of Max Horkheimer and Theodor Adorno as a process of (...) de-determination that finds its culmination in Derrida's notion of 'différance'. Set free of its totalizing, teleological force, Derrida's negativity as 'différance' is compared with Hegel's more general and generative notion of Negativität. The paper concludes that for this branch of 'critical' thinking, to flourish in the shadow of Hegel means also to be continually reinventing his respect for difference and negativity, and transforming it to respond to the questions of the present. Key Words: Adorno • Critical Theory • deconstruction • Derrida • dialectic • différance • difference • Hegel • Horkheimer • negativity. (shrink)