The reason why it's somewhat paradoxical coming from libertarians is for precisely the reasons we've been discussing in the comment thread of this post. Libertarianism is a political philosophy that forecloses many potential emergent orders in the non-market realm. Most pro-market economists who are non-libertarians have political philosophies that are much more amenable to ideas about spontaneous order. For the most part, we are constitutional democrats, right? We think that governments should be limited because we know about the incentive structures facing politicians and the distortions of government power. But we also know that you want to give the public a chance to shape their own laws, the way their society is organized, and you want to give the public the chance to experiment with that and change that and try new things over time. Most pro-market non-libertarian economists are of this view: constitutions are good and democracies are good, and there is no over-arching necessary political order that we pursue besides that. We all have our preferences for what we want the political order to look like, of course. But we don't take it as a philosophical necessity that the actual political order conform to that. The real important things are constitutionalism and democracy.
One would think that that is the environment where theorizing about spontaneous orders would flourish: an environment that is pro-market but also more democratic than libertarian. Libertarianism simply has too detailed plans about how the political order has to look: it's not spontaneous enough to be a natural home for spontaneous order.
So why did spontaneous order find a home among libertarians? I have a couple ideas.
- First I'm going to propose a "great man theory of history" - Hayek was simply a smart guy that got very interested in this stuff and wrote a lot of great stuff on it. Hayek was a libertarian, so it found a home among libertarians.
- Second, a lot of libertarian intellectuals were preoccupied with the socialist calculation debate at a time when non-libertarian pro-market economists were preoccupied with other research agendas. Ideas about spontaneous order were very relevant during this debate, so it found a natural home among libertarians - who were the most active in it.
- Third - again for historical reasons - a lot of libertarian economists were less concerned with developing predictive models, which made spontaneous order a more valid thing to talk about. If you're looking for predictive models, spontaneous order is going to interest you less - not because you think it's wrong but because it's hard to do anything predictive with it. Anyone who got excited about the Santa Fe Institute and that stuff found this out. One of the unfortunate outgrowths of this is that many libertarians have incorrectly concluded that modeling and appreciation of spontaneous order are mutually exclusive - which of course is ridiculous.
Anyway - if you think about it it's somewhat strange that a group of people with a very planned out view of what the political sphere should and shouldn't look like would have latched on to spontaneous order. But there you have it. The question is - in the future will the idea be claimed by non-libertarians? I think there's a broad enough appreciation of complexity that it will be - maybe not always with Hayek's language or with Hayek citations, but I think it is there already and it will only grow.