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arXiv · 1303.7336

A Graph Calculus for Predicate Logic

Paulo A. S. Veloso·Sheila R. M. Veloso
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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).

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Paulo A. S. Veloso, Sheila R. M. Veloso. 2013-03-29. A Graph Calculus for Predicate Logic. https://doi.org/10.4204/eptcs.113.15

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