The Search Efficiency of Theorem Proving Strategies

We analyze the search efficiency of a number of common refutational theorem proving strategies for first-order logic. We show that most of them produce search spaces of exponential size even on simple sets of clauses, or else are not sensitive to the goal. We also discuss clause linking, a new procedure that uses a reduction to propositional calculus, and show that it, together with methods that cache subgoals, have behavior that is more favorable in some respects