Consider the following premises. p_7 -> q_7. u -> p_7. ~q_7. p <-> u. Can we infer p from them?
 From p_7 -> q_7, ~q_7 we can infer ~p_7. From u -> p_7, ~p_7 we can infer ~u. Finally, from p <-> u, ~u we can infer ~p, which contradicts p. Therefore, the answer is no.