Writing has only been invented from scratch a handful of times in history

Nearly every writing system in use today descends, directly or by inspiration, from just a few independent inventions — cuneiform in Sumer, Chinese characters, and Mesoamerican scripts among the Maya and their neighbours, among others. Everywhere else, literate cultures learned the idea of writing from contact with one of these traditions rather than reinventing it themselves from nothing.

— Peter T. Daniels, William Bright (eds.), The World's Writing Systems — Oxford University Press, 1996
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