The concept of reasonableness is essential to John Rawls’s political liberalism, and especially to its main ideas of public reason and liberal legitimacy. Yet the somewhat ambiguous account of reasonableness in Political Liberalism has led to concerns that the Rawlsian distinction between the reasonable and the unreasonable is arbitrary and ultimately indefensible. This paper attempts to advance a more convincing interpretation of reasonableness. I argue that the reasonable applies first to citizens, who then play an important role in determining which (...) comprehensive doctrines and political conceptions of justice are reasonable. In addition, while Rawls fails to specify explicitly the meaning of the reasonable in his standard of political justification (i.e. the liberal principle of legitimacy based on the criterion of reciprocity), I offer an interpretation of what it means for citizens to present reasonable claims and arguments to one another in public reason. (shrink)