3 Mar 2004
CS3243 - Inference
39
Resolution: brief summary
lFull first-order version:
ll1 Ú ··· Ú lk,          m1 Ú ··· Ú mn
l(l1 Ú ··· Ú li-1 Ú li+1 Ú ··· Ú lk Ú m1 Ú ··· Ú mj-1 Ú mj+1 Ú ··· Ú mn)θ
l where Unify(li, Ømj) = θ.
l
lThe two clauses are assumed to be standardized apart so that they share no variables.
lFor example,
lØRich(x) Ú Unhappy(x)
l                  Rich(Ken)
lUnhappy(Ken)
l with θ = {x/Ken}
l
lApply resolution steps to CNF(KB Ù Øα); complete for FOL