The writer studies literature, not the world. He lives in the world; he cannot miss it. If he has ever bought a hamburger, or taken a commercial airplane flight, he spares his readers a report of his experience. He is careful of what he reads, for that is what he will write. He is careful of what he learns, because that is what he will know.
The writer knows his field – what has been done, what could be done, the limits – the way a tennis player knows the court. And like that expert, he, too, plays the edges. That is where the exhilaration is. He hits up the line. In writing, he can push the edges. Beyond this limit, here, the reader must recoil. Reason balks, poetry snaps; some madness enters, or strain. Now, courageously and carefully, can he enlarge it, can he nudge the bounds? And enclose what wild power? – Annie Dillard, The writing life