The mind which is created quick to love, is responsive to everything that is pleasing, soon as by pleasure it is awakened into activity. Your apprehensive faculty draws an impression from a real object, and unfolds it within you, so that it makes the mind turn thereto. And if, being turned, it inclines towards it, that inclination is love; that is nature, which through pleasure is bound anew within you.
They had their faces twisted toward their haunches and found it necessary to walk backward, because they could not see ahead of them. ...And since he wanted so to see ahead, he looks behind and walks a backward path.
The purpose of the whole [the Comedy] and of this portion [the Paradiso] is to remove those who are living in this life from the state of wretchedness, and to lead them to the state of blessedness.