Consider the following premises. ~Q_2(g_4). forall x_15: P_15(x_15) <-> Q_2(x_15). forall x_15: Q_2(x_15) -> P_15(x_15). p -> P_15(g_4). Can we infer p from them?
 From forall x_15: P_15(x_15) <-> Q_2(x_15) we can infer forall x_15: P_15(x_15) -> Q_2(x_15). From forall x_15: Q_2(x_15) -> P_15(x_15), forall x_15: P_15(x_15) -> Q_2(x_15) we can infer forall x_15: Q_2(x_15) <-> P_15(x_15). From forall x_15: Q_2(x_15) <-> P_15(x_15) we can infer Q_2(g_4) <-> P_15(g_4). From Q_2(g_4) <-> P_15(g_4), ~Q_2(g_4) we can infer ~P_15(g_4). Finally, from p -> P_15(g_4), ~P_15(g_4) we can infer ~p, which contradicts p. Therefore, the answer is no.