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 x_6, x_6 is sad. For all x_6, x_6 is excited. There is at least one x_6 for which if x_6 plays a game, then x_6 is not a poet. For all x_6, if x_6 were excited, then x_6 is a poet.
For all x_6, x_6 is a poet can be inferred via the universal modus ponens rule. For all x_6, x_6 is sad and x_6 is excited can be inferred via the universal conjunction rule. For all x_6, x_6 is excited and x_6 is sad can be inferred via the universal conjunction rule.