a side note to my sibling post about the bayesian truth serum, which can be used to surface "experts", is that BTS discovers experts by rarity of knowledge in the crowd and correctness of metaknowledge of the crowd. The existence of experts is a critical assumption. A corollary is that the maximal knowledge is bound by the crowd.

But also, since it's relative to the population, the knowledge of "experts" does not need to have any bearing on truth. I thought this would be a problem in our context, but then I thought, that's not so far from reality anyway!