Before a culture adopts the use of writing, when its knowledge is transmitted exclusively through oral means, it can very easily revise its history. It’s not intentional, but it is inevitable; throughout the world, bards and griots have adapted their material to their audiences and thus gradually adjusted the past to suit the needs of the present. The idea that accounts of the past shouldn’t change is a product of literate cultures’ reverence for the written word. Anthropologists will tell you that oral cultures understand the past differently; for them, their histories don’t need to be accurate so much as they need to validate the community’s understanding of itself. So it wouldn’t be correct to say that their histories are unreliable; their histories do what they need to do.
It struck me that what Chiang describes — quite favorably — as characteristic of an oral culture, i.e. the malleability of the past to serve the needs of the present, is exactly what Orwell was so appalled by in nineteen eighty-four.
By the way, Chiang is curiously prescient of today’s culture wars. The above story, from 2013, can serve as a literary illustration of "different ways of knowing", a phrase that has become so popular over the last couple of years. And the story Liking What You See: A Documentary, published in 2002, about a university campus-led fight against a kind of discrimination that is described as "lookism" is very reminiscent of the battles against modern-day isms.