In his criticism of the "illiberal liberalism" of this post, my friend Noah Millman makes several broader arguments against the metaphysically neutral form of liberalism I've been defending over the past few years (in the final chapter of my book, and in a recent blog post). Here are his objections:

Linker’s whole project . . . rests on the proposition that absent a neutral arbiter without metaphysical commitments you inevitably get social conflict. I pretty much disagree with that proposition whole-hog – I don’t think liberalism is (or can be) a wholly neutral arbiter without metaphysical commitments (indeed, I think this partly because I agree with some of liberalism’s metaphysical commitments); I don’t think such an arbiter would enable you to avoid social conflict (what would compel the loser to abide by the verdict?); and, for that matter, I think you can have devastating social conflict without any real disagreement about metaphysical commitments (those metaphysical commitments themselves may in many cases be “superstructure” rather than “substructure”).

Beginning with the last item first: I have never claimed (or believed) that a metaphysically neutral liberalism can help you avoid conflict altogether. On the contrary, politics is a never-ending series of conflicts without end. What liberalism does (or should try to do) is work to avoid distinctly political conflict about metaphysical questions. It does this by attempting to focus politics on securing the preconditions of what Aristotle called "mere life" (defense against external and internal threats; material prosperity) while channeling or deflecting questions wrapped up with "the good life" (God, the highest good for human beings, the content of happiness, the ranking of the virtues, etc.) into the private lives of the polity's citizens. One could therefore describe liberalism as a politics of the common good, albeit one that understands the common good in restricted terms. Whereas Aristotle believed that every political question involving "low" issues of public order and economic flourishing pointed toward (and presupposed) "high" metaphysical commitments that needed to be sorted out in the political realm, liberalism denies this -- saying, in effect, that politics can and should be conducted in mundane, prosaic terms without reference to metaphysics.

The benefit of this contraction of politics to "mere life" is that it renders less likely the most intractable forms of human conflict. But conflict over other, less fundamental matters -- about whether and what kind of economic stimulus we should pass, about how we should address climate change, about how we should respond to the threat of a nuclear-armed Iran, and so forth -- go on and on. Meanwhile, our metaphysical conflicts -- about whether there's a God, about whether and to what extent cultural changes in American life over the past fifty years should be celebrated, lamented, or actively opposed, about the proper place of self-restraint in a good human life -- take place primarily in the private sphere of civil society (in books and newspapers and magazines and blog posts, in the halls of universities and think tanks), with the state doing its best to stay out of it. 

(The issues that create the most problems for this view of liberalism are social issues such as abortion and gay marriage, because those on each side of those issues advance incompatible metaphysical claims. This is precisely why I think the common good would be advanced by bringing the Constitution back into a position of neutrality on abortion. On gay marriage, things are trickier, which means I'll deal with it in a separate blog post down the road.)

As for Noah's point about needing metaphysical appeals in order to "compel" the losing side in a social conflict to "abide by the verdict," I'm afraid I need to hear more details. But I wonder: Why isn't it enough for the losing side to accept that losing is one possible outcome of playing by the rules of liberal politics -- rules that benefit the losers as well as the winners in (other) innumerable ways? And anyway, is it really true that the losers in such a conflict would be more likely to abide by the verdict if the presiding judge based the verdict on metaphysical appeals? What if the losers don't share those metaphysical commitments? If not, wouldn't the appeal to metaphysics just make things worse?

This is ridiculously abstract, I know, but until Noah provides an example, that's all we have.