At Bleeding Heart Libertarians, Kevin Vallier has an interesting piece on the failure of “Enlightenment libertarianism” and the case for “post-Enlightenment libertarianism.” While I agree fully with Dr. Vallier’s critique of libertarian dogmatism in the Randian and Rothbardian modes, I have considerably more difficulty with the public-reason liberalism he associates with “post-Enlightenment” thinking.
You can’t prove a complete political or moral philosophy apodictically from self-evident axioms. That much is obvious. Somewhere along the way, you are going to have to make contestable assumptions. What Rand, Rothbard, and deductivist dogmatists of all stripes forget is a basic Humean (Enlightenment thinker!) humility about what reason is really good for. Reason helps us check whether arguments are valid, following inevitably from their premises, and whether premises are more or less likely to be true, by matching them against our observations of the external world or our internal moral compass (intuition). But any set of statements that is self-evidently or necessarily true is not going to have much substantive import or be widely applicable to the world we experience. The role of moral and political philosophy should therefore be to make clear the assumptions on which different normative judgments must rest and to assess the plausibility of those assumptions. Like any other political philosophy, libertarianism rests on contestable assumptions — ones I happen to regard as fairly plausible, but contestable nevertheless.
But what about “public reason” methodology — does that allow us a way out of the limitations inherent to intuition and deduction? As Dr. Vallier puts it: “The post-Enlightenment view still aspires to show that our diverse reasoning can lead us to converge on public principles that protect human freedom, but its aspirations are chastened. The fact of reasonable pluralism explains why many liberals have become public reason liberals, because treating others as free and equal requires admitting that the free use of practical reason leads in many different directions.”
As someone who occasionally reads contemporary political philosophy but is far from an expert, my novice’s take is that public-reason liberalism does not give us much purchase on controversial moral questions in Western societies. To the extent that public-reason philosophers are merely making modus vivendi, Augsburg-style arguments for liberalism, those arguments are potentially valuable as far as they go, but they cannot go far. Of course, public-reason theorists don’t think they are making mere modus vivendi arguments. But the more they diverge from mere modus vivendi argument (which has to be guided by empirical research, I might add), the more they tread into controversial moral territory of the “bad, old Enlightenment” rationality.
Take Rawls’ Political Liberalism for example. It’s been over a decade since I’ve read it, but I recall finding it far less persuasive than A Theory of Justice. Rawls, you change your methodology radically and just happen to end up reaching almost exactly the same conclusions (albeit with less scope for liberty)? Come on! There seem to be numerous controversial moral assumptions sneaked into his argument despite the overt concern for overlapping consensus among moral communities that radically disagree. Rawls’ theory of justice couldn’t even find overlapping consensus among the members of his own department.
So it seems to me we are stuck with the bad, old way of reasoning because there is no alternative. But certainly a little humility and open-mindedness are in order.