Consider the following premises. forall x_11: S(x_11). forall x_11: R_11(x_11) -> S_2(x_11). exists x_11: Q_11(x_11) -> S_2(x_11). forall x_11: ~P_11(x_11) or R_11(x_11). forall x_11: P_11(x_11) or Q_11(x_11). Can we infer forall x_11: ~(S_2(x_11) and S(x_11)) from them?
 From forall x_11: P_11(x_11) or Q_11(x_11), forall x_11: ~P_11(x_11) or R_11(x_11) we can infer forall x_11: Q_11(x_11) or R_11(x_11). From exists x_11: Q_11(x_11) -> S_2(x_11), forall x_11: R_11(x_11) -> S_2(x_11), forall x_11: Q_11(x_11) or R_11(x_11) we can infer exists x_11: S_2(x_11). Finally, from exists x_11: S_2(x_11), forall x_11: S(x_11) we can infer exists x_11: S_2(x_11) and S(x_11), which contradicts forall x_11: ~(S_2(x_11) and S(x_11)). Therefore, the answer is no.