John Rawls, "On the Idea of an Overlapping Consensus," Oxford Journal for Legal Studies 7 (1987): 1–25.
The aims of political philosophy depend on the society it addresses. In a constitutional democracy one of its most important aims is presenting a political conception of justice that can not only provide a shared public basis for the justification of political and social institutions but also helps ensure stability from one generation to the next. Now a basis of justification that rests on self- or group-interests alone cannot be stable; such a basis must be, I think, even when moderated by skilful constitutional design, a mere modus vivendi, dependent on a fortuitous conjunction of contingencies. What is needed is a regulative political conception of justice that can articulate and order in a principled way the political ideals and values of a democratic regime, thereby specifying the aims the constitution is to achieve and the limits it must respect. In addition, this political conception needs to be such that there is some hope of its gaining the support of an overlapping consensus, that is, a consensus in which it is affirmed by the opposing religious, philosophical and moral doctrines likely to thrive over generations in a more or less just constitutional democracy, where the criterion of justice is that political conception itself.