It is often said—and correctly, I think—to “follow the money” if you want to discover motive. But “useful for states” is another telling maxim worthy of our consideration. In Book III of The City of God, St. Augustine notes that
Varro, a very learned heathen, all but admits that these stories (about men like Aeneas, Romulus, and Julius Caesar descending from the gods) are false, though he does not boldly and confidently say so. But he maintains it is useful for states that brave men believe, though falsely, that they are descended from the gods; for that thus the human spirit, cherishing the belief of its divine descent, will both more boldly venture into great enterprises, and will carry them out more energetically, and will therefore by its very confidence secure more abundant success. (III.4)
We are wise to mind the narratives that are useful for states.