This gives new meaning to the phrase “Knowledge is power”.
I guess the priests were there to pass knowledge from one generation to the next and they eventually invented writing.
I don’t like the idea of requiring writing to be needed for the definition of a civilization since it seems clear that Egypt had a civilization long before the advent of writing.
I’m just surprised it took them so long to figure out a way to write down knowledge. Perhaps writing existed much further back in antiquity, but it was a closely guarded secret and not much evidence exists today of writing before 3000BC or so.