Rereading the long post below, it occurred to me that I didn’t mention why the argument I describe there should be called a “resilience” argument. Here’s what I had in mind. Institutions that have lasted for a long time have presumably endured in diverse circumstances while still producing tolerable outcomes, so we may think that there is a reasonable probability that they will still do ok in many unknown future circumstances: their endurance can be taken as evidence of resilience. If the potential costs of error in trying to find the optimal set of institutions are very high (e.g., getting a really bad political system, like the mixture of feudalism and Stalinism they have in the DPRK), and the “optimal” set of institutions for a given set of circumstances is very hard to find (if, for example, nobody knows with any certainty what the optimal political system would be for that set of circumstances, and the system would have to be changed anyway as they change), then it would make sense to stick with institutions that are correlated with ok outcomes over long periods of time and tolerate their occasional inefficiencies and annoyances. Resilient institutions are better than optimal institutions, given our epistemic limitations.
The argument also seems to imply that we ought to be indifferent about different sets of “ok” institutions. For example, there are a variety of democratic institutions in use today: some countries have parliamentary forms of government, some presidential; some have bicameral legislatures, others unicameral; some have FPP electoral systems, others use MMP; some countries use rules mandating “constructive” no confidence votes, others use other rules. But though we have some (statistically not especially good) evidence that some of these combinations work better than others (in some sets of circumstances: e.g., unitary parliamentary systems with list PR seem to produce better long-run outcomes than federal presidential government with nonproportional systems, at least on average, though I would not put too much stress on this finding), for the most part they all work ok, and we cannot tell with reasonable certainty whether some particular combination would be much better for us given foreseeable (and unforeseeable) circumstances. Perhaps switching back to FPP in New Zealand, for example, would produce better economic performance or induce better protection of civil liberties, but the best estimate of the effect of switching to FPP (or retaining MMP) on long run economic performance or the average level of protection of civil liberties is basically zero. (We might have reason to retain MMP or switch to FPP, but these will probably have more to do with normative concerns about representation and ideas about how easy it is for citizens to punish a government they dislike for whatever reason than with any special ability of MMP to deliver better economic performance). So we should not be bothered overmuch about these details of institutional design; given our epistemic limitations, on this view, it is unlikely that we would achieve even marginal improvements in our institutions that are sustained over the long run.
This does assume that gradual tinkering cannot at least serve to mitigate the effects of a changing “fitness landscape” (to use the terminology of the previous post), a controversial assumption. (It might be better to constantly tinker with our institutions than to let them just be, even if the tinkering is unlikely to lead to sustained improvements: we are just trying to stay on a local peak of the fitness landscape). And it also assumes that this landscape is very rugged for all the heuristics available: either minor changes just take you to another set of "ok" institutions (another variety of democracy, with some other combination of electoral system, relationships between executive and legislative powers, veto points, etc., and producing basically the same average long-run benefits), or they mostly throw you down a deep chasm if you try something new and radical (you get communist feudalism, or some variety of kleptocracy, and so on). I'm not sure this assumption makes sense for most problem domains, however: perhaps gradual tinkering in some cases does lead to better long-run outcomes, pace my previous argument against gradualism. But I have to think some more about this problem.