Kappel draws a useful distinction between different ways we diagnose dissent. Taking public dissent as his focus, Kappel examines what makes dissent epistemically good or bad, and what makes dissent reasonable or unreasonable. Kappel develops an account of reasonable and unreasonable dissent that is similar to Rawls’s account of reasonable and unreasonable political views, and offers some suggestions for responding to unreasonable dissent. One key conclusion that emerges is that when we diagnose dissent as reasonable or unreasonable we are rarely offering a mere description. More often this diagnosis is meta-level commentary on the manner in which we should treat the instance of dissent in question. Thus, the labeling of dissent as reasonable or unreasonable is itself often a political act.