Teaching people to argue is crucial to any notion of rhetorical citizenship, but in a democracy that is, at best, representative, it is at least as important to teach critical monitoring of public argument. For that we need norms of reasonable disagreement. I shall argue that the central norm, and the one most often flaunted, is the obligation to give honest replies to counter-considerations and critical questions. This requires debaters to make honest and explicit comparisons between pros and cons, recognizing that both are usually real and relevant, yet incommensurable, so that reasonable disagreement may persist.