But there is a problem; because, as Rawls also rightly observed, there is more than one humanist worldview that supports a liberal ethos. Presumably, a single set of public institutions and rituals cannot simultaneously affirm a variety of worldviews without sounding impossibly dissonant and incoherent. Rawls's solution was to argue that they should affirm only the "overlapping consensus" — whose content is mainly ethical and thinly anthropological — while keeping silent about any of the thicker metaphysical hinterlands. I have explained why I doubt that it is either possible or desirable for "public reason" to keep silence in this way. So if liberal public institutions and rituals cannot limit their affirmation simply to a common ethic, then they must choose one supportive humanist worldview to represent. I say that they must choose one, because I assume that a single national set of public institutions and rituals cannot simultaneously affirm rival doctrines.

So one must be chosen; but which? One candidate for public comprehensive doctrine is an atheist version of Kantianism, although it would need to become significantly more liberal and less dogmatically secularist than French republicanism. Or liberal institutions could choose an ecumenical monotheism, as the US Constitution permits and American governments have in fact chosen.  Or they could choose Trinitarian Christianity, as has the Republic of Ireland. Or they could choose Anglican Christianity, as in England.

As an expression of orthodox Christianity, Anglicanism is structurally humanist in its credal affirmation of the special dignity of human being made in the image of God — a dignity intensified by God's assumption of human flesh in the Incarnation. According to this high vision, human beings are not merely the random result of the blind operation of physical forces, nor their activity simply determined by genes or chemistry, nor their asserted significance just so much desperate whistling in the enveloping cosmic dark. No, in Christian eyes humans are the creatures of a benevolent divine intelligence, which has striven through natural evolution to create individuals who flourish in freely understanding and investing themselves in the truth about the world's good.

In such a vision, there is truth — be it sometimes complex and internally plural — to be understood: as the creation of the one wise God, the world possesses a given rationality that is there for rational beings to grasp. Since human beings are not only rational but finite and fallible, and since they are made to flourish in society, their reasoning needs to be social: they need to reason together. Conversation, therefore, is an important social endeavour. It is not properly an occasion for the egotistical display of wit, for the scoring of points, for the assertion of superior rhetorical power, or for the domination of the weak. It is rather about the common searching out of the truth, and common deference to its authority.