A reduction-based theorem prover for 3-valued logic

Abstract

We present a new prover for propositional 3-valued logics, TAS-M3, which is an extension of the TAS-D prover for classical propositional logic. TAS-M3 uses the TAS methodology and, consequently, it is a {\em reduction-based\/} method. Thus, its power is based on the reductions of the size of the formula executed by the $\efe$ transformation. This transformation dynamically "filters" the information contained in the syntactic structure of the formula to avoid as much distributions (of $\land$ wrt $\lor$ in our case) as possible, in order to improve efficiency. In our opinion, this filtering is the key of the TAS methodology which, as shown in this paper, allows the method to be extremely adaptable, because switching to different kinds of logic is possible without having to redesign the whole prover.