A story told, staged or written within the work itself, which mirrors or comments on the main story.
In Inferno
neither the sweetness of a son, nor the piety for the old father [...] the ardor I had to become expert in the world, in human vices and in worth.
Ulysses recounts to Virgil and Dante his last voyage, from within the flame. The story he relates is a story within Dante's story, and the one who tells it is the damned man himself, who explains himself to the one who listens.
I did not weep, so petrified had I become inside: they wept; and my Anselmuccio said: you look so, father! What is wrong with you?
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