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_14, if x_14 were a mechanic, then x_14 is sad. Jessica is a mechanic. If Jessica were a politician, then Jessica is not sad.
There is at least one x for which x is a mechanic can be inferred via the existential generalization rule.