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_14(a_14). ~s. forall x_14: R_14(x_14) -> S_14(x_14). u_1 <-> s.
~S_14(a_14) and ~s can be inferred via the conjunction rule. ~s and ~S_14(a_14) can be inferred via the conjunction rule. u_1 -> s can be inferred via the biconditional elimination rule. s -> u_1 can be inferred via the biconditional elimination rule. ~u_1 can be inferred via the biconditional elimination rule.