The fragments are a wonderful symbol of our fragmentary knowledge. It’s like a giant jigsaw puzzle that we puzzle about because we don’t have the original picture. Each new discovery leads to a new discovery in our thinking. Of course there can be duplication as there are duplication in all our written text. It is a rare find that we have such a rare find in our trove of ancient texts and sources.
That statement pretty much applies to all of human history prior to the 19th century