A Graph Calculus for Predicate Logic
arXiv:1303.7336 · doi:10.4204/EPTCS.113.15
Abstract
We introduce a refutation graph calculus for classical first-order predicate logic, which is an extension of previous ones for binary relations. One reduces logical consequence to establishing that a constructed graph has empty extension, i. e. it represents bottom. Our calculus establishes that a graph has empty extension by converting it to a normal form, which is expanded to other graphs until we can recognize conflicting situations (equivalent to a formula and its negation).
In Proceedings LSFA 2012, arXiv:1303.7136