Raymond Chandler on literature:
When a book, any sort of book reaches a certain intensity of artistic performance it becomes literature. That intensity may be a matter of style, situation, character, emotional tone, or idea, or half a dozen other things. It may also be a perfection of control over the movement of a story similar to the control a great pitcher has over the ball. Every page throws the hook for the next. I call this a kind of genius.
(From a letter by Raymond Chandler to Earl Stanley Gardner.)