What lessons did ancient Mesopotamians learn?

Answer 1

To manage water by dams and canals promoted food security and economic activity.

That a system of writing helped record keeping in commerce, government and religion.

That combining to form a city-state allowed the beneficial of mutual effort to raise living standards and security.

That warfare was beneficial in both defending your own city-state and extracting profit from other cities.

Combining city-states together had benefits in economic, cultural and defence activity.

That the gods were fickle.