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 y_1, y_1 is a lawyer or y_1 will not climb a mountain. There is at least one y_1 for which if y_1 were a lawyer, then y_1 is climbing a mountain.
For all y_1, if y_1 climbs a mountain, then y_1 is a lawyer can be inferred via the universal rewriting rule.