In the Aeneid there is a tendency to dissociate action from emotion. Action is often dictated by a strong sense of duty, while emotion, instead of being a motivating power, becomes an idle accompaniment that contradicts the meaning of the act. This is most clearly observed in the person of Aeneas, particularly in those Odyssean books when he schools himself in a ‘new heroism’ whose very basis seems to depend on such a dissociation. Thus, in the midst of Troy's destruction, his natural desire is to die fighting for his city. If he had acted out this desire (as he begins to do) he would have been conforming to the standards of the old, Homeric, heroism. But he is caught in the complicated fabric of Rome's future, and the old, simple heroism, founded on a natural and impulsive nobility, is not for him. He must go against his natural desire and, as a runaway, escape the doomed city to refound it elsewhere. And yet his heart is set on the city he has lost, not on the city he must build, as becomes clear in the succeeding books. In Book iii he envies the miniature Troy which Helenus and Andromache have built in Epirus, while in Book iv he longs to stay with Dido and share in her city. The division he so frequently evinces in these early books between what he has to do and what he wants to do can be considered as part of a training in pietas, in devotion to his highest duty, which is consummated in the underworld encounter with his father Anchises in Book vi.