Consider the following premises. forall x_18: Q_14(x_18) -> R(x_18). forall x_18: U_4(x_18) <-> R(x_18). forall x_18: U_4(x_18). Can we infer ~R(f) from them?
 From forall x_18: U_4(x_18) <-> R(x_18) we can infer forall x_18: U_4(x_18) -> R(x_18). From forall x_18: U_4(x_18) we can infer forall x_18: U_4(x_18) or Q_14(x_18). Finally, from forall x_18: U_4(x_18) -> R(x_18), forall x_18: Q_14(x_18) -> R(x_18), forall x_18: U_4(x_18) or Q_14(x_18) we can infer forall x_18: R(x_18), which contradicts ~R(f). Therefore, the answer is no.