Natsume Sōseki’s novel Kokoro ran in the Asahi Shimbun from April 20 to August 11, 1914. Its three parts are “Sensei and I,” “My Parents and I” and “Sensei and His Testament.” A young man meets an older man whom he calls sensei. In the last part, sensei leaves him a letter, a testament, that tells the story of his life.
A bookstore column calls it the work used most often in junior and senior high school Japanese textbooks.