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: If John drives a car, then Robert is a writer. If Robert were a writer, then William is a scientist. If William were a scientist, then James is working. If James works, then John is driving a car.
If John drives a car, then William is a scientist can be inferred via the transitivity rule. If Robert were a writer, then James is working can be inferred via the transitivity rule. If William were a scientist, then John is driving a car can be inferred via the transitivity rule. If James works, then Robert is a writer can be inferred via the transitivity rule.