From The Atlantic : "In the fall of 1938, Radcliffe College sophomore Frances Turnbull sent her latest short story to family friend F. Scott Fitzgerald. His response, found in F. Scott Fitzgerald: A Life in Letters (UK; public library)—the same volume that gave us Fitzgerald's heartwarming fatherly advice and his brilliantly acerbic response to hate mail—echoes Anaïs Nin's insistence upon the importance of emotional investment in writing and offers some uncompromisingly honest advice on essence of great writing:"
(What he says is that sort of sincere advice you may hear in any creative position you're in, if you are very lucky enough to have someone like this speak to you. It is honest and worth more than all the praise and ego-stroking you can want or bargain for. It all depends on the person who hears these sort of words when it does happen. Read at the link).