1. S v P 2. P -> (A -> B) 3. ~(W -> S) 4. R -> ~(B -> ~A) :. ~R =================================== 5. ~(~W v S) 3: Material Implication 6. W & ~S 5: De Morgan 7. ~S 6: Conjunctive Elimination 8. P 7, 1: Disjunctive Syllogism 9. A -> ~B 8, 2: Modus Ponens 10. ~A v ~B 9: Material Implication 11. ~B v ~A 10: Commutativity 12. B -> ~A 11: Material Implication 13. ~(~(B -> ~A)) 12: Double Negation Introduction 13. :. ~R 13, 4: Modus Tolens