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: If William were a soldier, then William is playing tennis. For all x_8, if x_8 plays tennis, then x_8 is a poet. For all x_8, if x_8 were a poet, then x_8 is a soldier.
For all x_8, if x_8 plays tennis, then x_8 is a soldier can be inferred via the universal transitivity rule.