Blog ping pong may not be the ideal way to hash out the fundamental differences between conservative and libertarian approaches to tradition and fallibilism, so let me just restrict myself to a couple quick comments on Jonah Goldberg's response to my post of last Friday . (Jonah's original review is now online, by the way.)
First, Jonah notes (correctly enough) that however much I celebrate the relentless internal scrutiny of science, I'm still "certain" that "science is better than voodoo" and that liberal pluralism is preferable to totalitarian theocracy. But that was precisely my point. Jonah thinks that attending to our own fallibility, emphasizing the need for humility and doubt, will leave us too timorous to defend our own values. But a robust confidence in the meta-structures of scientific inquiry, on the one hand, and liberal democracy, on the other, is not just compatible with such a skeptical attitude, it depends upon it. Jonah's own argument is actually of the same form: He's essentially giving process-based reasons to think longstanding traditions are sound, even though, from our necessarily limited perspective, they will often seem prima facie irrational.
Second, I'll allow that describing Jonah's view as a demand to "freeze" culture is a bit of a caricature—albeit one that the institutional clarion call "stand athwart history yelling stop!" might be thought to invite. The real question, then, is when to defer and when to mutate. Hayek provides some guidance here, suggesting a preference for "immanent" criticism over wholesale rationalist redesign—a paradigm example being Frederick Douglass' "The Meaning of July Fourth for the Negro," which argued that America was already implicitly committed to racial equality. I think it's significant (to return to where this all started) that Andrew Sullivan chose conscience, itself an evolved and culturally permeated faculty, as the proper lodestone. And, since Jonah's picked the example of gay marriage, I'll point out that the argument for including gay couples didn't drop out of the blue: It proceeds from familiar and deeply rooted liberal principles of equality under the law, and a shared understanding of the importance (for many people, anyway) of marriage to a fullfilled human life, combined with the relatively recent recognition that homosexuality is not, in fact, a species of mental illness. It is not obviously more dramatic than various other institutional adaptations marriage has undergone over the last few centuries—arguably less so, since the change involves only a small fraction of the population. My goal here is not to kick off yet another debate over gay marriage, about which I've written plenty already, but to point out that the theoretical framework Jonah's appealing to doesn't justify just a general deference to tradition per se, but rather a wariness toward projects of wholesale, ground up reconstruction—replacing marriage societywide with Na-style sibling clusters, say.
Finally, under the headline "Julian, Me and Justin Makes Three," Jonah links to a post in which "Justin Katz tries to get between me and Julian Sanchez." Jonah, I'm flattered, even a little curious, but you're a married man. Still, let me just address one qualm about the analogy between skeptical science and liberal societies. Katz doubts it will go through because while scientists have the shared goal of improving science (let this rather rosy view of actual scientists' motivations pass for the moment), the diverse members of a liberal society are trying improve their own lives. So let me make explicit what I was implicitly gesturing at in the original post: See Mill for the full argument there. With Mill and Nozick, I very much doubt there will be a One Best Way of Life if "Way" is understood to involve much detail, but also expect that people's self-interested "experiments in living" provide publicly benificial information without that being anyone's explicit intention.
Update: Well, I'd hoped I could get away with just outsourcing the meat of the argument here to Mill, as it's both familiar and unlikely to benefit tremendously from my paraphrase. But since Katz's follow-up post concludes I must not have understood his original objection, I suppose a bit of elaboration's in order. Nothing about the picture I'm painting here requires (as we do expect in science) convergence on some one or few models. This is possible, but I find it highly unlikely, and I imagine the optimal mix will change as conditions and populations do. All that's required is that people be similar enough that exposure to a variety of other people's "experiments in living" provides data to people trying to shape their own lives, whether or not they draw the same lessons from that data. If the result of this were, as Katz proposes, large numbers of people embracing Catholic sexual ethics over time, while I doubt I'd find this particularly congenial personally, I don't think it'd affect my attitude toward the general process, the point of which is not to produce the aggregate scenario I personally find most congenial.