Commentary Inf V 140

We now realize that during the entire episode we have not heard a word from Paolo. Dante will return to this strategy when he twice again involves pairs of sinners in suffering together, Diomedes with Ulysses in Inferno XXVI, Ruggieri with Ugolino in Inferno XXXIII. In each case one of the two is a silent partner. We can try to imagine what an eternity of silence in the company of the voluble being who shares the culpability for one's damnation might be like.