You who are living refer every cause up to the heavens alone, as if they of necessity moved all things with them. If it were so, free will would be destroyed in you, and there would be no justice in happiness for good or grief for evil. The heavens initiate your movements: I do not say all of them, but supposing I did say so, a light is given you to know good and evil, and free will, which if it endure fatigue in its first battles with the heavens, afterwards, if it is well nurtured, it conquers completely. You lie subject, in your freedom, to a greater power and to a better nature.
Dante, Purgatorio, Canto XVI