How Writing Came About
About 3000 BCE, a sheep-owner (or perhaps the owner’s accountant) in the neighborhood of Uruk got tired of keeping track of large numbers of sheep by making large numbers of marks, each meaning either “a sheep” or “a flock of (10) sheep”. Instead, he borrowed a symbol used to represent a big measure of grain — 60 bags full — and put it before the symbol for a sheep. That afternoon, this fellow invented abstract numbers, and also invented the notation that would eventually be the writing we know. (Other people invented writing in China and in Mesoamerica; it's possible there were even earlier scripts that didn’t catch on.)