A brief reference, without explanation, to a person, a text, a myth or a fact known outside the work, which carries with it the meaning of that other story.
In Purgatory
O vain glory of human powers! how briefly the green lasts at the top, if it is not followed by coarse ages! Cimabue thought he held the field in painting, and now Giotto has the cry, so that the fame of the former is dimmed.
The names "Cimabue" and "Giotto" call to the scene two painters whom Dante's reader knew. The reference needs no explanation and makes the exchange of one fame for another an example that all can check.
not only once, going around this space, is our pain refreshed: I say pain and should say consolation, because that will leads us to the trees, which led Christ joyfully to say Eli, when he freed us with his blood.
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