Try a bunch of queries; read good-looking papers, not for their results, but their discussion of background information. There's no real good solution to the problem of known unknowns: "I'm sure this has been researched, but what's the exact phrase or name it's been given in academia?" I suspect this is one of the benefits of being in the community - when you discuss something or mention an idea, they can say 'ah yes, X' and now you have not the problem of an unknown known but the much much easier problem of a known unknown which you can just punch into Google Scholar and get to work.
read good-looking papers, not for their results, but their discussion of background information.
That's a really good idea! I usually skip introductions and go for the "meat" of the results, just realized that it's bitten me several times already, guess it's time to unlearn that habit.
About a month ago I accidentally found out that the LW idea of quining cooperation is already studied in academia:
1) Moshe Tennenholtz's 2004 paper Program Equilibrium describes the idea of programs cooperating in the Prisoner's Dilemma by inspecting each other's source code.
2) Lance Fortnow's 2009 paper Program Equilibria and Discounted Computation Time describes an analogue of Benja Fallenstein's idea for implementing correlated play, among other things.
3) Peters and Szentes's 2012 paper Definable and Contractible Contracts studies quining cooperation over a wider class of definable (not just computable) functions.
As far as I know, academia still hasn't discovered Loebian cooperation or the subsequent ideas about formal models of UDT, but I might easily be wrong about that. In any case, the episode has given me a mini-crisis of faith, and a new appreciation of academia. That was a big part of the motivation for my previous post.