The question of antagonism, struggle and dissensus, and their place, limits and value for democracy, has divided deliberative from agonistic theories in recent years and remains the main source of the impasse between them. This open access book seeks to break this impasse by going back to their sources in Kant (for deliberative theories) and Nietzsche (for agonisms) and reframing them as philosophers of conflict. For both philosophers, conflict is part of the ‘deep structure’ of reality at all levels, and their reflections on its constitutive, constructive and destructive potentials raise fundamental questions that democratic theories can ill afford to ignore. Through a series of text-based comparative studies of Kant’s and Nietzsche’s philosophies of conflict, Herman Siemens addresses the central question of the book: What does it take to think of conflict, real opposition or contradiction as an intrinsic dimension of reality? Drawing on Kant’s pre-critical writings and his historical-philosophical texts and Nietzsche’s philosophical physiology and the will to power, chapters examine topics such as logical opposition (contradiction) versus real opposition (Realrepugnanz); idealism as philosophical warfare; the relation between war and peace; destructive versus constructive forms of conflict; resistance as a stimulant; Kant’s ‘unsociable sociability’ and Nietzsche’s ‘fine, well-planned, thoughtful egoism’; hatred, revenge and the ‘slave revolt in morality’. The eBook editions of this book are available open access under a CC BY-NC-ND 4.0 licence on bloomsburycollections.com. Open access was funded by the Dutch Research Council.