From GTC to Reset: Generating Reset Proof Systems from Cyclic Proof Systems

Abstract: We consider cyclic proof systems in which derivations are graphs rather than trees. Such systems typically come with a condition that isolates which derivations are admitted as 'proofs', known as a the soundness condition. This soundness condition frequently takes the form of either a global trace condition, a property dependent on all infinite paths in the proof-graph, or a reset condition, a 'local' condition depending on the simple cycles only which, as a result, is typically stable under more proof transformations. In this article we present a general method for constructing cyclic proof systems with reset condition from cyclic proof with global trace conditions. In contrast to previous approaches, this method of generation is entirely independent of logic's semantics, only relying on combinatorial aspects of the notion of 'trace' and 'progress'. We apply this method to present reset proof systems for three cyclic proof systems from the literature: cyclic arithmetic, cyclic G\"odel's T and cyclic tableaux for the modal {\mu}-calculus.