egoism as a psychological theory
No Longer Human (人間失格, Ningen Shikkaku) is a Japanese novel by Osamu Dazai. Published after Run Melos and The Setting Sun, No Longer Human is considered Dazai’s masterpiece and ranks as the second-best selling novel in Japan, behind Natsume Sōseki’s Kokoro.
The literal translation of the title, discussed by Donald Keene in his preface to the English translation, is “Disqualified from Being Human”. (The Italian translation was titled Lo squalificato, The Disqualified.)
This novel, despite being serialized as a work of fiction in 1948, is narrated in the first person and contains several elements which betray an autobiographical basis, such as suicide—a recurring theme in the author’s life. Many also believe the book to have been his will, as he took his own life shortly after the last part of the book was published, on June 13, 1948.
One modern analyst has proposed Dazai was suffering from complex post-traumatic stress disorder when he wrote the book.