A taxonomy of theorem-proving strategies

This article presents a taxonomy of strategies for fully-automated general-purpose first-order theorem proving. It covers forward-reasoning ordering-based strategies and backward-reasoning subgoal-reduction strategies, which do not appear together often. Unlike traditional presentations that emphasize logical inferences, this classification strives to give equal weight to the inference and search components of theorem proving, which are equally important in practice. For this purpose, a formal notion of search plan is given and shown to apply to all classes of strategies. For each class, the form of derivation is specified, and it is shown how inference system and search plan cooperate to generate it.