6.B Extended Metaphor and Which Traits Transfer (FIG-1.T)

A metaphor states that one thing is another. An extended metaphor keeps that one comparison alive for a whole poem by feeding it new material: added images, similes, and specific details that all belong to the same vehicle. A poem comparing a marriage to a house does not just say 'marriage is a house' four times. It adds the rooms nobody uses, the door that swells in wet weather, the guttering they argued over. Each addition is a new claim about the marriage, so the metaphor accumulates meaning instead of restating it.

Any vehicle offers a whole bundle of possible traits, and a poem only ever transfers some of them. A grandmother compared to a lighthouse might take the lighthouse's reach, its record-keeping, its endurance through weather, while refusing the isolation or the automation a real lighthouse also has. That refusal is not an oversight. Readers are meant to notice what got left on the shore, because the missing traits shape the meaning as much as the chosen ones do.

Sit this metaphor next to the other devices in the unit: like personification, it depends on deciding exactly which qualities cross from one thing to another; like allusion, it asks a reader to track a reference across an entire text rather than one line. Watch what happens when a late detail stops fitting the vehicle, the way a river 'dug by hand' breaks a comparison that had been selling the career as natural and inevitable. That break is often the poem's real argument, arriving right when the metaphor seems most settled.