MATH.19:4.4 - Change the carried claim when a step needs more
At a stalled step, inspect what it actually consumes. It may need the claim for a different parameter, an additional retained quantity, or all smaller inputs instead of only the immediate predecessor.
Strengthen or generalize the carried claim to supply that information, then recheck its starting cases and every affected step. MATH.4 develops the corresponding inductive constructor and property proof. A stronger hypothesis inside an induction argument must come from the chosen induction principle and its proved cases.
Adding a new premise is a different repair. It narrows the theorem’s applicability. Check whether the receiving problem supplies that premise; otherwise the revised theorem answers a changed question. The changed commutation condition in :5.2 demonstrates this boundary.
The argument may also need a different representation. MATH.17 supplies operations on operations, and MATH.18 compares interpretations when that change can make the missing mathematical relation available.