This essay describes Derrida's later articulations of the logical; of the ‘undeniable’ and its constant denial. Against anti-realist readings of Derrida as some sort of textual idealist, I show how Derrida's thinking of the undeniable informs his deconstruction of the death penalty in the recently published 1999–2001 lecture courses, as well as the considerations of mortality and finitude that inform all of his writings.