Every book has an intrinsic impossibility, which its writer discovers as soon as his first excitement dwindles. The problem is structural; it is insoluble; it is why no one can ever write this book.
From a galvanising 1989 piece by Annie Dillard for the New York Times. A vivid, powerful expression of the art of writing if ever I’ve read one.
(Thanks to T.B. McKenzie for the link.)