Robert Greene describes the descent of power:
Let us imagine a tribe of some 1000 people in some place in ancient times. We could say this tribe had a certain amount of power, based on its wealth and resources. The majority of this power, the control over it, was in the hands of one man — the ruler, the king. He might, in this case, depend on a small cadre of people to assist him, but he largely determined the roles they could play.
Let us say, with success and prosperity, this tribe grew to a size of some 10,000. Now, such supreme concentration was too difficult. The ruler would have to bring in others — advisers, generals, high priests. He could keep this number relatively limited and the percentage of power was mostly in his hands, but now ever so slightly diluted. If this town evolved into a city of some 100,000, suddenly there came a qualitative change. The complexity of ruling such numbers grew exponentially. Power at this moment had to be genuinely distributed in order to maintain a sense of control. Now there were teams of ministers, the military, the growing aristocracy and its court. To service this administration, bureaucracies had to evolve. Power remained concentrated, but with a different scale of distribution.
We can make three generalizations at this point. When a group of people is given power, it forms a power center. This means, for instance, that a team of military leaders tends to think in two directions — how to promote the interests of the ruler, while also advancing its own agenda. Things now become political, as their interests will clash with other power centers. The ruler must now manage this growing complexity. The power environment becomes increasingly dangerous.
Second, once people have been given power on this level, they do not want to give it back or return to an older way of governing. They work to keep what they have and extend their power base. And finally, once power becomes diluted and divided this way, it tends to keep on dividing, like a split atom. More and more people must be brought in to keep the whole functioning. And so over the course of centuries, power slowly became less and less concentrated.