Truth is a chameleon. Filtered through the the personality of a professional it can take on many shapes. Politicians, sales people, con men use it creatively to feather their own nests. Authors, poets, artists and even musicians filter it in quite another way.
And yet, in the hands of a master, even a fantasy can shine a light on Truth. Nobody seriously believes in hobbits, elves, giant cave-dwelling spiders, or magicians, and yet Tolkien had much truth in his work. He showed that even a small, weak person's courage can overcome a stronger opponent; he showed that a respected sorcerer can be seduced by the lust for power; he showed the triumph of self-sacrifice and bone-wearying courage; he showed the struggle between good and evil and highlighted their precarious balance.