For me the click came while finishing To Mock a Mockinbird by Raymond Smullyan. https://en.wikipedia.org/wiki/To_Mock_a_Mockingbird https://en.wikipedia.org/wi

For me the click came while finishing To Mock a Mockinbird by Raymond Smullyan. https://en.wikipedia.org/wiki/To_Mock_a_Mockingbird https://en.wikipedia.org/wiki/To_Mock_a_Mockingbird Smullyan "tricks" you into deriving the Gödel Incompleteness Theorem from the BCKW combinator calculus.