The commitment to provide an “adequate justification” of binding political decisions that is accepted or proves acceptable by all citizens concerned, appears to be one of the distinctive features of the idea of deliberation in the public arena as it is conceived by many deliberative conceptions of democracy. Having said that, however, not only is it not at all clear what exactly would qualify as “adequate justification” but also something even more basic: how are we to interpret the term “justification” (...) in political contexts? In this essay I shall present two models of public justification. The first one, is associated with a traditional epistemological idea of justification of beliefs and involve some common sense notions about the subject. The second model, particularly influential in recent liberal political philosophy, stipulates that providing good reasons does not suffice to justify a belief or set of beliefs before others. There must be an appeal to reasons that are accepted –or may come to be accepted as a result of the deliberative process itself– by the subject providing the justification as well as by those he addresses. The aim of this essay is to develop an argument in support of this second model of public justification. (shrink)