The Sumerian, 1000 years before the Egyptians, wrote on clay tablets, because the clay industry is far more obvious than the papyrus one. Assyriologists usually agree that arithmetic started for accounting of livestock and harvest. Sumerians also invented financial calculus to evaluate the return of investments. Religion as a state administration appeared later after the invention of arithmetic and writing.

The paradox is that Mesopotamians wrote millions of tablets that have been hidden under the sand and recovered only recently, while Egyptian wrote less but build stunning monuments that are visible still after thousands of years.