Consider the following premises. forall x_12: U(x_12) <-> W(x_12). forall x_12: ~Q_1(x_12). exists x_12: U(x_12) -> Q_1(x_12). Can we infer forall x_12: W(x_12) from them?
 From forall x_12: U(x_12) <-> W(x_12) we can infer forall x_12: W(x_12) -> U(x_12). From exists x_12: U(x_12) -> Q_1(x_12), forall x_12: ~Q_1(x_12) we can infer exists x_12: ~U(x_12). Finally, from forall x_12: W(x_12) -> U(x_12), exists x_12: ~U(x_12) we can infer exists x_12: ~W(x_12), which contradicts forall x_12: W(x_12). Therefore, the answer is no.