Consider the following premises. forall x_10: P_10(x_10). forall x_10: P_10(x_10) -> Q_10(x_10). u -> ~Q_10(a_9). Can we infer u from them?
 From forall x_10: P_10(x_10) -> Q_10(x_10), forall x_10: P_10(x_10) we can infer forall x_10: Q_10(x_10). From forall x_10: Q_10(x_10) we can infer Q_10(a_9). Finally, from u -> ~Q_10(a_9), Q_10(a_9) we can infer ~u, which contradicts u. Therefore, the answer is no.