This essay examines debate in Milton's work, especially his late poems, and in the thought of Jürgen Habermas. I argue that Paradise Lost, Paradise Regained, and Samson Agonistes offer forms of debate highly resistant to the proto-Habermasian version of communicative action advanced in the early Areopagitica. Each of these three late poems casts a Habermasian hallmark - persuasion by force of the better argument — in starkly sinister lights.