The language of the common good, like the language of property which exemplifies it, is Janus-faced. Looking back it points to a concrete givenness of community, a present and existing form within which we have been given to communicate with others, and which we cannot ignore without great blame. Looking forward, it can invite us to think of a City of God, a sphere of universal community, and encourage us to seek intimations of it from the future. But only so far can it take us. It cannot ease us through the portals of the City of God up the steps of a ladder of dialectical reconciliations.
To the extent that it can open the imagination to be receptive to a further future, it can serve us. But what will take possession of the open imagination? A word of promise from the self-revealing God of the future, to be grasped by faith and hope? Or seven devils worse than those of the past that have been cast out? Nothing in the idea of the common good itself can answer that question for us. Nothing can spare us the task of discerning the prophets.