This essay discusses William V. Spanos’s work as the legacy of what can be called “onto-political criticism.” Spanos’s affiliation between texts and the world discloses the overlapping of the history of imperialistic and colonial violence with the politics of ontology, what constitutes the discourses, ideologies and institutions that produce and consolidate the metaphysics of imperialism. Drawing on Martin Heidegger and the poststructuralists, Spanos’s work demonstrates how metaphysics is not inconsequential; it is the discursive and political reproduction of a certain concept of being as a measure for other humans and as a philosophical and political justification for their dispossession, enslavement and extermination that is the very fist act of colonization. His insistence on the poststructuralists’ legacy of an antihumanist practice that desires to articulate the poetics and politics of the ontologies of alterity is not indifferent to politics. Spanos thus unearths the “overlapping territories and intertwined histories” (Said) constitutive of the polis within the histories of colonialism, imperialism and neo-imperialism, the latter being his key focus in his analyses of American exceptionalism in the age of globalization. His onto-political a-filiation establishes the possibility of articulating a kind of criticism that, while recognizing the history of this axiomatics of ontopology, also imagines and articulates the potentiality that is ex-centric (the derivative and negative prefix “a-” signifies this) to its narratives, discourses and politics. Spanos’s legacy opens the possibility for a community of method driven by “the thought of a differential polity,” a constitutive element of a truly democratic politeia.