Problems Yet to Be Addressed

• Resolution rule is only applicable to sentences that are in the form P1 v P2 v ... v Pn, where each Pi is a negated or un-negated predicate and contains functions, constants, and universally quantified variables, so can we convert every FOL sentence into this form?

• How to pick which pair of sentences to resolve?

• How to pick which pair of literals, one from each sentence, to unify?