Throughout The City and Its Uncertain Walls, characters meditate on their relationship to time and how it impacts their decisions and their identity. Characters outside the walled-in city understand their identities as the product of remembered experiences. The protagonist often reflects on how years of living with heartbreak hinder him from finding love, while Mr. Koyasu understands his connection to memory as a life force. Mr. Koyasu, who appears as a ghost, debates the nature of the human soul and settles on the notion that his continued existence is connected to his consciousness and memory: “But what I’ve learned after dying is that you can’t see the soul with your eyes or touch it with your hands. You can’t use it to do anything special. In my opinion, what we actually can rely on is consciousness, and memories” (202). For Mr. Koyasu, his mind and his memories propel him through death into the realm of the afterlife. His continued presence in the library is fueled by his consciousness and memories of his life, and these become his entire identity. Though his body cannot withstand the forces of time, his mind can. For Mr.