When Soseki Natsume wrote the first chapter of his debut novel I AM A CAT, he probably did not expect to become a professional novelist.
He was busy teaching at a university and a high school, and the whimsical novella was never intended to be anything more than a temporary sway from his daily routine.
It proved to be hugely popular, and the general public demanded for more. Soseki wrote the sequel to the novella, completing the voluminous I AM A CAT, and went on to write quite a few masterpieces, and became arguably the most important writer of fiction in Japanese history since Lady Murasaki of the Tale of Genji.
It is quite interesting to observe that the writing of I AM A CAT provided a much needed release of emotion, stress, and joy for the young scholar. It was literally a solace for his soul. It is often the case that something written for the welfare of the writer or those around him goes on to become something of a universal value. A similar example might be Alice in Wonderland by Lewis Carroll, written to amuse a little girl that the mathematician knew personally.