Consider the following premises. p_1 -> p_2. p_2 <-> R_10(a_10). forall x_10: ~R_10(x_10). Can we infer p_1 from them? If possible, name the inference rules being used at each step.
 From forall x_10: ~R_10(x_10) we can infer ~R_10(a_10) via universal instantiation. From p_2 <-> R_10(a_10), ~R_10(a_10) we can infer ~p_2 via biconditional elimination. Finally, from p_1 -> p_2, ~p_2 we can infer ~p_1 via modus tollens, which contradicts p_1. Therefore, the answer is no.