“All good books have one thing in common — they are truer than if they had really happened.”

A Letter from Cuba (1934)

Source: The Instructions

The Fabric of Reality (1997)

Source: The Chronicles of Prydain (1964–1968), Book V : The High King (1968), Chapter 21
Context: “How then?” Taran asked. “Could The Book of Three deceive you?”
“No, it could not.” Dallben said. “The book is thus called because it tells all three parts of our lives: the past, the present, and the future. But it could as well be called a book of ‘if.’ If you had failed at your tasks; if you had followed an evil path; if you had been slain; if you had not chosen as you did — a thousand ‘ifs,’ my boy, and many times a thousand. The Book of Three can say no more than ‘if’ until at the end, of all things that might have been, one alone becomes what really is. For the deeds of a man, not the words of a prophecy, are what shape his destiny.”

Paris Review interview (1958)
Context: From things that have happened and from things as they exist and from all things that you know and all those you cannot know, you make something through your invention that is not a representation but a whole new thing truer than anything true and alive, and you make it alive, and if you make it well enough, you give it immortality. That is why you write and for no other reason that you know of. But what about all the reasons that no one knows?

and the jumper says, "Story of my life, man" and other guys start to smile but he's dead. That's a true story that never happened.
The Things They Carried (1990), How to Tell a True War Story

McKenna Grace [citation needed]

Daily Mail, March 2008