Consider the following premises. ~p. p <-> S(a_8). forall x_8: S(x_8) or S_8(x_8). Can we infer S_8(a_8) from them?
 From forall x_8: S(x_8) or S_8(x_8) we can infer S(a_8) or S_8(a_8). From p <-> S(a_8), ~p we can infer ~S(a_8). Finally, from S(a_8) or S_8(a_8), ~S(a_8) we can infer S_8(a_8). Therefore, the answer is yes.