Post-Gedankenexperiment Speculative Questions

Matsya comes to the rescue of Manu

Assuming for the purpose of play the prior post, 

And assuming say a time point of what we would date as around say, 3000-4000 CE/AD,

What would be the mix of religions?

The simplification our species would have gone through would probably be the most drastic one yet, at least since that mysterious big human population drop about 70,000 years ago. So I doubt the current religious systems would make it through the cusp, like in this wonderful novel.

We can with some confidence in a general sense I believe, predict what governance and social methods/structures may arise. That is because we have matches from the past to go with previous socio-technological levels of complexity.

Of course, the wild card on this is the following.:

What knowledge of past human history (the time before the relatively sudden

decrease in human population) would make it through the cusp?

What form and accuracy would it entail?

Assuming the simplification is geographically inconsistent, would some surviving groups have a technical advantage or experiential advantage in competition for resources?

Would that past become mythic elements, and how long would that take?

We have seen this process in our actual past, after non-planetary-wide  simplifications, (Early post Roman Britain views on “Rome”, or the drastic simplification in a short time across the Western Hemisphere from the spread along trade routes of the diseases brought to the Caribbean by the first Europeans to come ashore there. But this time, the rapid simplification would be on a planetary scale.

For some perhaps, the actual Simplification with be reimagined and weaved into some great story. This would be not unlike how probably the human experience the flooding around the planet with the melting of the last ice age, eventually became all the human flood epics, from the flood in the Epic of Gilgamesh to flood Legend of Manu.