Steven Beattie offers a vivid example in the Globe and Mail recently:
Fiction and history share a symbiotic relationship. Though the latter provides the raw material for the former, it is often fiction that has the stronger claim on truth, if “truth” is to be understood as emotional or affective, as opposed to baldly factual. Fiction, by definition, traffics in “alternative facts,” and is transformative; by approaching history through the prism of story and technique, the fiction writer is paradoxically able to access deeper wells of understanding about our relationships to the world and to each other.Alternative facts, really? A lot of fiction writers will know this is nonsense, I think. They share Roger Ebert's dictum about movies: "it's not what the movie is about, it's how it goes about it." Film-making or story-making, it is about the craft. Well-made stories persuade us, not to believe, but only to suspend disbelief. A story is supposed to feel true, but that does not make it True, only persuasive.
Beattie, on the other hand, is arguing that if the shells are moved about with enough skill, then the guy who says the pea is under this particular shell must be telling us the truth.
This is a faith, not a critical stance. It's a claim that fiction is the superior form of writing, by definition, and all others are lesser. It is fictionism, not criticism, and it's ultimately a form of bigotry.
Nonfiction, just to be clear, should never expect a reader to suspend disbelief. If it "reads like a novel," you should probably distrust its claims. Nonfiction doesn't achieve truth, but it is the genre where claims to truth can best be compared and evaluated.
I have started collecting examples of this "fiction is true; history/nonfiction is not" ideology. There must be a million out there, as the fictionist ideology is thriving these days. Contributions of fresh examples would be welcomed.