1. E > (S > T) 2. (~L * M) > (S * E) 3. ~(T v L) // ~M ------------------------------------------------------- 4. (E * S) >T 5. ~T * ~L 6. ~T 7. ~(E * S) 8. ~(S * E) 7 Commutation 9. ~(~L * M) 2,8 Modus Tollens 10. ~~L v ~M 9 De Morgan's Law 11. L v ~M 10 Double Negation 12. ~L * ~T 5 Commutation 13. ~L 12 Simplification 14. ~M 11,13 Disjunctive Syllogism