In ancient Egypt, the Nile would flood once a year.
This was actually a very good thing, as the Nile brought in needed silt that would enrich the crops.
Other places didn’t have such luck, as their soil would tend to get more and more depleted over time.
Stacked Up Ruins
A lot of ruined cities lay on top of one another.
Just like today, the main three components of real estate is location, location, location.
Cities that were near water source, decent soil for crops and natural kinds of fortification were few and far between.
Jericho, the oldest city in the world, has all three of these.
After the Roman collapse and leading into the middle ages, farmers had a very slim seed ROI.
For every one seed they planted, after they harvested all the stuff, they just barely enough seeds to plant the next crop.
One theory about the growth of society is an overall EROI, or energy return on investment.
As civilizations are on the upswing, they tend to produce far more than they consume, giving them a net surplus of energy.
But once they start consuming more than they are producing, this becomes problematic.
This is where the metaphor of eating your seed corn comes into play.
They aren’t producing enough to feed everybody, so their grain stores are slowly depleting.
This becomes particularly devastating when they use up all their resources.
Eat Each Other
This is when hunger and panic sets in, and historically when is when many people resort to cannibalism.
By the end of the high middle ages, they had increased their seed ROI to up to 400%.
This is what allowed a lot more food to be produced, which allowed for a lot more people.
Of course, this was right around the black death showed up and killed one out of three, effectively thinning the herd significantly.
One example of a bunch cities on top of one another is Troy.
For a while they thought Troy was a myth.
Until they found a whole bunch of Troys stacked up on top of one another.
Because the Nile flooded everywhere, ancient Egyptians didn’t have to worry so much about crop rotation.
Ever year the Nile would essentially reset the soil to maximum levels of food productivity.
Making ancient Egypt a very unique location.
Mind Persuasion has plenty of books and courses to teach you how to speak hypnotically and persuasively.