Re:What about 8000 years ago? (Score 1)

The single greatest invention in the history of mankind was agriculture.

This is absolutely correct. Before the dawn of agriculture some 10,000 years ago, all human societies consisted of small bands of hunter-gatherers, typically numbering around 25 men, women and children per group; there were no such things as "societies" - as we currently understand the term - to speak of, no permanent settlements people could call their "homelands," no nations, not even cities.

Only with the transition from a life of hunting, gathering and scavenging (yes, that too!) did the rudiments of "civilization" begin to emerge. Annual crops like wheat and barley needed long-term tending, necessitating fixed settlement. The carrying capacity of given areas of land exploded, making possible first villages, then small towns and later the first cities. The larger settlements made possible a division of labor without precedent in human history - farmers, merchants, artisans, soldiers, administrators and the like.

Vast hierarchies emerged, of a sort men had never before seen. Divine kings and high-priests replaced the chief-hunter or shaman of yesteryear. Slavery and state-building, in the form of monuments like ziggurats and pyramids, came into being. States were born of the ambitions of rival rulers, and with these new states, vast wars, permanent standing armies, and notions of nationalism and ethnic rivalry.

The complex new social structures gave impetus to the drive to record all sorts of information that was necessary for administrative efficiency - the quantity of taxes levied and paid, the amount of grain harvested, the number of adult males available for military service - and from this sprang the second most important invention of all time - writing. (It is interesting to note that the first attested usage of writing, by the Sumerians, was for the recording of contracts by administrators and tax collectors.)