Herbrand Sequent Extraction

Focusing on the extraction of essential information from complex mathematical proofs, this book presents four algorithms designed to derive a Herbrand sequent from proofs in Gentzen's Sequent Calculus LK for classical First-Order Logic. It introduces a Herbrand sequent as a generalization of Herbrand disjunction, emphasizing its role in summarizing the creative aspects of formal proofs, particularly regarding quantifier instantiations. One algorithm is implemented in CERes, an automated system aimed at enhancing proof transformations and analysis.