Post #2586852

@tila@girldick.gay Non-wellfounded set theory is a thing, where sets are allowed to contain themselves. It's relatively consistent with normal set theory. The deeper problem embedded in Russell's Paradox is assuming that the extension of a logical statement is a set. Now, there is a certain sense in which non-wellfounded set theory and more typical set theory can make the same statements, so it isn't intrinsically interesting to those interested in the foundations of math. On the other hand, non-wellfounded set theory did inspire some of my weirder work: https://hackage.haskell.org/package/control-monad-queue-0.2.0.1