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: Patricia is a taxi driver. For all x_5, x_5 is happy or x_5 is not a taxi driver.
There is at least one x for which x is a taxi driver can be inferred via the existential generalization rule. For all x_5, if x_5 were a taxi driver, then x_5 is happy can be inferred via the universal rewriting rule.