Naming a thing by another that is linked to it: the part for the whole, the object for its owner, the place for its people, the cause for the effect.
In Paradise
one opposes the yellow lilies to the public sign, and the other appropriates it for a party, so that it is hard to see who errs more
The "yellow lilies" take the place of the party that bears them as its emblem. Instead of naming the faction, the verse shows the flower, and the eagle, the "public sign", stays in the middle as what the two sides dispute.
Cantos V to VIII: Mercury and Venus, Justinian, judging Guelphs and Ghibellines
in shepherd's garb, ravening wolves can be seen from up here in every pasture: O defense of God, why do you still lie? With our blood, Cahorsines and Gascons prepare to drink: O good beginning, to what vile end you must fall!
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