To me, the least real thing in maths is, ironically, the real numbers.
As you dig through integers, fractions, square roots, solutions to polynomials, things a turing machine can output, you get to increasingly large classes of numbers which are still all countably infinite.
At some point I realised I'd covered anything I could ever imagine caring about and was still in a countable set.
As you dig through integers, fractions, square roots, solutions to polynomials, things a turing machine can output, you get to increasingly large classes of numbers which are still all countably infinite.
At some point I realised I'd covered anything I could ever imagine caring about and was still in a countable set.