How can we live together when we disagree in the midst of our deepest differences? asked Os Guinness in his 2008 The Case for Civility. In a month that has seen violent clashes across the US, his question is more relevant now than when he wrote the book. The civility he advocates isn't a soft or easy toleration. It's not "niceness and mere etiquette or dismissed as squeamishness about differences." It doesn't require us to lay aside our convictions to engage in public debate. On the contrary: "each of us who talks and debates with others does so with the full integrity of who we are, and not as neutered by some illiberal demand that we drop the faith that is the core of who we are and the animating vision by which we see the world." Civility is a "tough, robust, substantive" republican virtue. It doesn't shrink from public disagreement, but engages with respect and fairness. In short, "But civility is not for wimps; it is competitive. It is first and foremost a matter of political debate rather than an attempt at shortcutting through judicial decision. Important political differences have to be 'fought out' in the public square, but the term fight is now only a metaphor, and winners have their responsibilities as well as losers their rights. In other words, political debates are won and lost, and policies and laws come and go, but all within the bounds of what is mutually agreed to be in the interests of the common good." It's boxing with Queensberry rules. One still has to box. Guinness argues for the formation of a civil public square, in contrast to the naked public square of secularism, the sacral public square of Christendom, or, especially, a public square that has turned into a culture war battleground. Guinness understands that "political civility" has to be founded; it doesn't just happen. Civility "is forged within a covenanted framework, or charter, of the three Rs of religious liberty—rights, responsibilities, and respect." He offers a vision of a "global public square" constituted "through covenant pluralism." In his model, "everyone in the world is free to believe what they choose to believe, on the basis of freedom of conscience; but, as with the civil public square, they have to accord the same freedom to others, and learn to live with a double eye—one to the integrity of their own faiths, and the other to the responsibility of seeing and dealing with others through the lens of their faiths." In the US, a legal, Constitutional frame is essential but law can't resolve all public issues. Resort to law is like doing surgery with a club instead of a scalpel. Civil engagement requires "a freely and mutually agreed covenant, or common vision for the common good, of what each person understands to be just and free for everyone else, and therefore of the duties involved in living with the deep differences of others." Guinness is quite right that the civility he advocates requires a common framework, and his appeal to the biblical conception of "covenant" is welcome. Yet his proposal won't work. The problem isn't merely the obvious pragmatic one: How do we get everyone to agree on the rules of the game? The proposal is internally incoherent. Consider: A "common vision for the common good" requires some agreement on the terms. What is good? What is common? Is there in fact such a reality as a "common good" to which we can aspire? These questions touch on the deepest convictions that we hold. But we disagree on those most fundamental convictions. How can a framework that assumes agreement serve to regulate fundamental disagreements? To put it otherwise: If we could agree on the rules of the game, we wouldn't need to have this conversation in the first place. Consider again: "Covenant" is a loaded term, with a specifically Judeo-Christian provenance. How long would it take someone to object that Guinness is simply playing the old imperial games of Christendom, imposing a Christian order on our pluralistic society? Answer: Not very long; it would be almost instantaneous. His proposal fails for another reason too. Answering the objection that his proposal requires the formation of a "civil religion," Guinness shifts rhetorical gear. What has been a "covenant" is now described as a "civil public philosophy." And he insists that it is "secular; it is not a civil religion, and it must never be elevated into being religious. A civil public philosophy is a matter of the common vision for the common good, the shared agreement about the rights, responsibilities, and respect that form the common bonds within which Americans can live freely and debate important differences." This relies on an exceedingly narrow conception of religion. And, besides, what of those who are convinced that no common good can be good if it ignores God? Aren't we lurching back toward the naked square? It's a sign of the times that this earnest proposal, full of wisdom and charity, offered by one of today's leading Christian thinkers, should be stillborn.