Debates about the nature of the Enlightenment date to the eighteenth century, when Immanuel Kant himself addressed the question, 'What is Enlightenment'? The contributors to this ambitious book offer a paradigm-shifting answer to that now-famous query: Enlightenment is an event in the history of mediation. Enlightenment, they argue, needs to be engaged within the newly broad sense of mediation introduced here - not only oral, visual, written, and printed media, but everything that intervenes, enables, supplements, or is simply in between. With essays addressing infrastructure and genres, associational practices and protocols, this volume establishes mediation as the condition of possibility for enlightenment. In so doing, it not only answers Kant's query; it also poses its own broader question: how would foregrounding mediation change the kinds and areas of inquiry in our own epoch? "This Is Enlightenment" is a landmark volume with the polemical force and archival depth to start a conversation that extends across the disciplines that the Enlightenment itself first configured.