Consider the following premises. forall x_13: Q_4(x_13). forall x_13: U_2(x_13) <-> Q_13(x_13). forall x_13: U_2(x_13) -> W(x_13). forall x_13: U_2(x_13) or ~Q_4(x_13). Can we infer exists x_13: ~W(x_13) from them?
 From forall x_13: Q_4(x_13) we can infer forall x_13: Q_4(x_13) or Q_13(x_13). From forall x_13: U_2(x_13) or ~Q_4(x_13) we can infer forall x_13: Q_4(x_13) -> U_2(x_13). From forall x_13: U_2(x_13) <-> Q_13(x_13) we can infer forall x_13: Q_13(x_13) -> U_2(x_13). From forall x_13: Q_4(x_13) -> U_2(x_13), forall x_13: Q_13(x_13) -> U_2(x_13), forall x_13: Q_4(x_13) or Q_13(x_13) we can infer forall x_13: U_2(x_13). Finally, from forall x_13: U_2(x_13) -> W(x_13), forall x_13: U_2(x_13) we can infer forall x_13: W(x_13), which contradicts exists x_13: ~W(x_13). Therefore, the answer is no.