Definition of Allegory
Foer embeds an allegorical frame story within Extremely Loud & Incredibly Close through "The Sixth Borough," a bedtime tale Oskar's father tells him. In this whimsical, magical-realist narrative, New York City once had a sixth borough beyond the familiar five. Over years, "a millimeter at a time, the Sixth Borough receded from New York," until its bridges collapse and tunnels snap. Before it's gone entirely, the residents anchor Central Park in Manhattan, ferrying it across while children sleep on the grass and dream into the night sky.
As a frame story, "The Sixth Borough" exists as a complete, self-contained narrative inside the main one. It has its own setting, events, and logic, filtered through Oskar's memory of his father's voice. The placement of this tale within the larger book mirrors the way family stories and folktales are passed down.
As an allegory, the drifting borough stands in for the inevitability of separation. The city's desperate attempts to hold on and its eventual acceptance of loss parallel Oskar's own journey. When his father tells him this story, Oskar doesn't yet know that it is a lesson about grief. Sometimes the people we love will move away from us, and we must find a way to preserve what we can while still letting go.