I'd settle for "earliest known", without an assumption that there was probably an older one.
Much like fossils, the vast majority of human writing is quickly lost to posterity. Paper, bark, and string decompose; clay and rock break; all writing materials can be repurposed for other writing (palimpsets) or other uses (reshaped to wall stones).
Still, given the paucity of known, independently invented writing systems... We may well know of all of them.
Much like fossils, the vast majority of human writing is quickly lost to posterity. Paper, bark, and string decompose; clay and rock break; all writing materials can be repurposed for other writing (palimpsets) or other uses (reshaped to wall stones).
Still, given the paucity of known, independently invented writing systems... We may well know of all of them.