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: Joseph is cooking. For all x_7, x_7 will not listen to a song or x_7 is a scientist. For all x_7, x_7 will not cook or x_7 is a writer.
There is at least one x for which x will cook can be inferred via the existential generalization rule.