What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Name the inference rule being used: ~s. s -> p_3. p -> s. p_3 -> p.
~p can be inferred via the modus tollens rule. s -> p can be inferred via the transitivity rule. p -> p_3 can be inferred via the transitivity rule. p_3 -> s can be inferred via the transitivity rule.