Consider the following premises. forall x_17: T(x_17) or ~Q_17(x_17). exists x_17: ~P_15(x_17) or Q_17(x_17). forall x_17: R_11(x_17) -> T(x_17). forall x_17: P_15(x_17) or Q_15(x_17). forall x_17: T(x_17) -> S(x_17). forall x_17: ~Q_15(x_17) or R_11(x_17). Can we infer forall x_17: ~S(x_17) from them?
 From forall x_17: T(x_17) or ~Q_17(x_17) we can infer forall x_17: Q_17(x_17) -> T(x_17). From forall x_17: P_15(x_17) or Q_15(x_17), exists x_17: ~P_15(x_17) or Q_17(x_17) we can infer exists x_17: Q_15(x_17) or Q_17(x_17). From exists x_17: Q_15(x_17) or Q_17(x_17), forall x_17: ~Q_15(x_17) or R_11(x_17) we can infer exists x_17: Q_17(x_17) or R_11(x_17). From forall x_17: Q_17(x_17) -> T(x_17), forall x_17: R_11(x_17) -> T(x_17), exists x_17: Q_17(x_17) or R_11(x_17) we can infer exists x_17: T(x_17). Finally, from forall x_17: T(x_17) -> S(x_17), exists x_17: T(x_17) we can infer exists x_17: S(x_17), which contradicts forall x_17: ~S(x_17). Therefore, the answer is no.