What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? There is at least one x_17 for which if x_17 were a poet, then x_17 is not taking a plane. For all x_17, x_17 is a poet and x_17 will play a game. For all x_17, x_17 will take a plane and x_17 is a cashier.
Since the premises are contradictory, we can infer anything from them.