TBH, the construction of Riemann surfaces from the natural numbers is pretty well understood by the average UK undergraduate. (Natural->Integer->Rational->Real-

TBH, the construction of Riemann surfaces from the natural numbers is pretty well understood by the average UK undergraduate. (Natural->Integer->Rational->Real->Complex->Foundations of Reimann Surfaces). The expression of the rules of natural numbers in ZFC is fully understood by far fewer, but that’s mostly because it’s tedious.