Commentary Purg III 52-57

Virgil's question and attitude reveal a guide who has not taken this trip previously, as he had in Inferno.  Further, while he falls back on the resource of his reason, the futility of which in certain situations has just been explored by the guide himself, his pupil, like the arriving penitents in the last canto (see C.Purg.III.40-45), does the intuitive and hopeful thing: he looks up.