A correspondence problem for mathematical proof
The Standard View holds that informal proofs justify their conclusions by indicating a corresponding formal derivation. The notion of 'correspondence' between a particular informal proof and a particular formal derivation is left unanalyzed.
The authors distinguish thin readings (any derivation of the theorem) from thick readings (a derivation corresponding to the proof). They analyze correspondence into two criteria: adequate representation of the theorem and tracking of the proof's steps. They examine existing formalization practice, mainly Lean and mathlib4, including a Euclid primes example, AlphaProof outputs, tactic use, library lock-in, and the sphere packing formalization. They identify structural, causal, and explanatory routes to establishing correspondence.
Establishing correspondence is argued to be a defeasible, quasi-empirical achievement. Its robustness comes from convergence across independent modes, which AI-generated proofs and library constraints can weaken.
