The existential crisis that hits when you learn about Gödel's Incompleteness Theorem is too real! Suddenly you're questioning if your breakfast cereal choice is an unprovable statement within its axiomatic system.
For the uninitiated, Gödel basically shattered mathematics by proving that in any consistent formal system complex enough to express basic arithmetic, there will always exist true statements that cannot be proven within that system. So now you're pointing at literally everything going "Wait... is THAT unprovable too??"
Mathematical completeness? Sorry, it's just not on the menu. Your formal system is either inconsistent or incomplete. Pick your existential nightmare!