Consider the following premises. p_17 <-> t. ~t. forall x_20: R_20(x_20) and S_20(x_20). Can we infer p_17 from them?
 From forall x_20: R_20(x_20) and S_20(x_20) we can infer R_20(a_20) and S_20(a_20). Finally, from p_17 <-> t, ~t we can infer ~p_17, which contradicts p_17. Therefore, the answer is no.