One of the overarching themes of A Tale for the Time Being is the concept of time. The novel explores the way in which Nao and Ruth exist in different moments in time but come together through Nao’s diary. In particular, the novel is concerned with the Zen Buddhist concept of time, particularly the idea of “the time being” drawn from Dōgen’s famous philosophical work, Shōbōgenzō. In the Shōbōgenzō, Dōgen writes that “every being that exists in the entire world is linked together as moments in time, and at the same time they exist as individual moments of time. Because all moments are the time being, they are your time being” (259). This concept of time helps to explain how Nao and Ruth come to be connected. Although they both exist as separate moments in time, they are also linked together because they exist as part of the universe. In the opening sentence of the novel, Nao describes herself as a “time being” because she is a being who exists in time. She explains: “A time being is someone who lives in time, and that means you, and me, and every one of us who is, or was, or ever will be” (3).