Metamathematics by Kleene. Fairly accessible math, mostly new and developed from the start it takes one into compatibility theory and formalization of maths in

Metamathematics by Kleene. Fairly accessible math, mostly new and developed from the start it takes one into compatibility theory and formalization of maths in a way that makes Godel easy to understand and just full of cool ideas that are very relevant to today’s world of computers and the limits to certainty.