Consider the following premises. forall x_6: T_4(x_6) <-> Q_3(x_6). forall x_6: P_6(x_6). exists x_6: P_6(x_6) -> T_4(x_6). Can we infer forall x_6: ~Q_3(x_6) from them?
 From exists x_6: P_6(x_6) -> T_4(x_6), forall x_6: P_6(x_6) we can infer exists x_6: T_4(x_6). From forall x_6: T_4(x_6) <-> Q_3(x_6) we can infer forall x_6: T_4(x_6) -> Q_3(x_6). Finally, from forall x_6: T_4(x_6) -> Q_3(x_6), exists x_6: T_4(x_6) we can infer exists x_6: Q_3(x_6), which contradicts forall x_6: ~Q_3(x_6). Therefore, the answer is no.