Commentary Inf XXXI 19-27

Dante's confusion, as he peers through the mist, causes him to take giants for towers. If we ever come to believe, as very few do, that Cervantes had read Dante, this scene will serve as one of the strongest pieces of evidence, since Quijote makes the obverse mistake, taking windmills for giants. For the medieval works on optics that lie behind the description of Dante's misperceptions here, see Dronke (Dron.1986.1), p. 36.