Generating proofs with spider diagrams using heuristics

Abstract

We apply the A¤ algorithm to guide a diagrammatic theorem proving tool. The algorithm requires a heuristic function, which provides a metric on the search space. In this paper we present a collection of metrics between two spider diagrams. We combine these metrics to give a heuristic function that provides a lower bound on the length of a shortest proof from one spider diagram to another, using a collection of sound reasoning rules. We compare the effectiveness of our approach with a breadth- first search for proofs.