The discussion centers around the undecidability of a Consistent and Sufficiently Strong Axiomatized Formal Theory (AFT), with references to the Diagonal Argument and its application. Participants clarify that AFT refers to Axiomatized Formal Theory and emphasize the importance of formal proofs, particularly those verified by proof assistants like Coq and Isabelle. Key points include Church's theorem, which establishes that pure first-order predicate calculus is undecidable by demonstrating that Turing machines can be encoded within it, and the undecidability of Robinson's system Q, which shows that computable functions can be represented in Q. The diagonal argument is highlighted as crucial for proving Gödel's second theorem regarding the incompleteness of Peano Arithmetic. Recommended resources for further reading include the Open Logic Project books and "Computability and Logic" by Boolos et al.