I think this thought has analogues in Bayesian statistics.
We choose a prior. Let’s say, for the effect size of a treatment. What’s our prior? Let’s say, Gaussian with mean 0, and standard deviation equal to the typical effect size for this kind of treatment.
But how do we know that typical effect size? We could actually treat this prior as a posterior, updated from a uniform prior by previous studies. This would be a Bayesian meta-analysis.
I’ve never seen anyone formally do a meta-analysis just to get a prior. At some point, you decide your assumed probability distributions are close enough, that more effort wouldn’t change the final result. Really, all mathematical modeling is like this. We model the Earth as a point, or a sphere, or a more detailed shape, depending on what we can get away with in our application. We make this judgment informally, but we expect a formal analysis to back it up.
As for these ranges and bounds… that reminds me of the robustness analysis they do in Bayesian statistics. That is, vary the prior and see how it effects the posterior. Generally done within a parametric family of priors, so you just vary the parameters. The hope is that you get about the same results within some reasonable range of priors, but you don’t get strict bounds.
Very interesting. A few comments.
I think you mentioned something like this, but Drexler expected a first generation of nanotechnology based on engineered enzymes. For example, in “Engines of Creation”, he imagines using enzymes to synthesize airplane parts. Of course the real use of enzymes is much more restricted: cleaning products such as dishwasher detergent, additives in food, pharmaceutical synthesis. It has always seemed to me that someone who really believed Drexler and wanted to bring his imagined future about would actually not be working on anything like the designs in “Nanosystems”, but on bringing down the cost of enzyme manufacturing. From that perspective it’s interesting that you note that the most promising direction in Drexlery mechanosynthesis is DNA origami. Not quite what Drexler imagined (nucleic acid rather than protein), but still starting with biology.
Also, I think it’s very interesting that silicon turned out to be easier than diamond. While I agree with Yudkowsky that biology is nowhere near the limits of what is possible on the nanometer-scale due to constraints imposed by historical accidents, I disagree with Yudkowsky’s core example of this, the weak interactions holding proteins in the folded configuration. Stronger bonds make things harder, not easier. Maybe the switch from diamond to silicon is an illustration of that.
Editing to add one more comment… Drexler’s definition of “diamondoid” is indeed strange. If we take it literally, it seems that glass is “diamondoid”. But then, “diamondoid” microbes already exist, that is, diatoms. Or at least, microbes with “diamondoid” cell walls.