At a USC talk in 2011, Kojima said he began writing as a young man…

Kojima placed the start of his deliberate narrative writing in junior high, when a teacher assigned converting a few lines of kanbun into modern Japanese and expanding them into a story. He reinterpreted those lines into roughly ten pages, received special praise from the teacher in front of the class, and shifted from merely documenting plots like movie synopses to trying to write real narratives.

“this is exactly the kind of thing I have always wanted to create. Not a game merely played to "pass the time", but something that would be important to one's own life experience.”

According to the Newsweek profile of him in 2001, Kojima wrote in middle school five 600-page science-fiction novels.

Kojima recalled that twenty-five years earlier he had incorporated a story and a message into video games when both were regarded as unnecessary. With the rise of mobile games used to kill time, he saw Minagawa’s literary activity at age eighty-two as the baton to receive. He promised to continue as he is even after turning eighty and to instill his memes into video games.

After he began writing, Kojima had no mentor, isolated himself, and nurtured a sense of superiority while producing stories that were not published. Upon entering senior high he continued writing but stopped submitting his work to competitions; he recognized in the poet Li Zheng the same mix of timid pride and disdainful shyness—that is, a fear that a lack of talent might be revealed and a rejection of the effort required to cultivate it.