This paper surveys the meaning of the pen name ′Yi Sang(李箱)′ in the light of the arbitariness of language and the relationship among names, observing in three ways how the images of ′Sang′ (Box) appear differently in his works. In Particular, we look into (1) the relationship between a box and its inner boxes, (2) the divisional relationship in the box, and (3) the relationship between the box and an outer box. In Yi Sang′s work, image (1) gives shape to the relationship between the writer himself and his ancestors who are responsible for his present existence. Image (2) gives shape to two internally divided Yi Sangs, and is symbolized as a mirror that reflects two selves. Image (3) gives shape to a relationship between himself in the closed world and other people and/or a bigger outside world. All these symbolic relationships are fully represented in his work "Nalgae" (The Wing)". What is interesting is that Yi Sang has already employed these box images in his earlier poetry "Geonchuk-muhan-yukmyeon-gaucho" (Infinite Architectural Hexagon). furthermore, by visualizing his name as a sqaure($square$), he means to suggest the intentional image of his pen name as a ′box′.