“Writing is a long and lonesome business; back of the problems in thought and composition hover always the awful questions: Is this the page that shows the empty shell? Is it here and now that they find me out?”

Source: Autobiography of Mark Twain, Vol. 2 (2013), p. 281

Shadow and Act (New York: Random House, 1964), Introduction, p. xix; in The Collected Essays, ed. John F. Callahan (New York: Modern Library, 1995), p. 56.

Source: The Wind-Up Bird Chronicle

"The Sadistic Muse" - an interview with Laura Miller at salon.com (10 February 1998) http://web.archive.org/web/20000110052318/http://www.salon.com/books/int/1998/02/cov_si_10int.html
Context: It's been said that happiness writes white. It doesn't show up on the page. When you're on holiday and writing a letter home to a friend, no one wants a letter that says the food is good and the weather is charming and the accommodations comfortable. You want to hear about lost passports and rat-filled shacks.

Source: Atop an Underwood: Early Stories and Other Writings

Paris Review interview (1956)
Context: For me writing is a question of finding a certain rhythm. I compare it to the rhythms of jazz. Much of the time life is a sort of rhythmic progression of three characters. If one tells oneself that life is like that, one feels it less arbitrary.

Brett Thomas (October 16, 1988) "Roth 'N' Roll: Flashy - But David's A Shrewd Businessman", The Sun-Herald, Section: News and Features, p. 25.