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: For all z, z will go running. For all x_8, if x_8 goes running, then x_8 is a lawyer. For all x_8, if x_8 were a lawyer, then x_8 is running.
For all x_8, x_8 will go running if and only if x_8 is a lawyer can be inferred via the universal biconditional introduction rule. For all x_8, x_8 is a lawyer if and only if x_8 will go running can be inferred via the universal biconditional introduction rule.