
Originally Posted by
Adam Strange
We can trace low birth rates back to a common source.
Birth rates typically fell in the past because children became too expensive to raise.
Children became too expensive to raise when the income or the resources required to raise them were in short supply.
Resources become scarce when they have been over-exploited.
Civilization is an active process that requires resources to maintain itself.
If there are insufficient resources to maintain a civilization at its present level of complexity, it will inevitably have to “simplify”. This can result in fewer people and can appear to be a “fall” from previous levels of complexity.
This happens to all civilizations eventually. The Roman Empire was entirely solar-powered and expanded by stealing the stored resources of its neighbors. When it reached the limits of groups reachable by easily traversed rivers or constructed roads, it found itself with a lot of complexity and nothing to power it. The Romans had to simplify. Birth rates fell precipitously in the first centuries of the present era.
When Spain discovered areas which could grow sugar (a human fuel), it expanded. When the British discovered the oil fields of Iraq, they expanded. When the US was able to gain control of petroleum supplies, it expanded.
Unfortunately, the external costs of burning fossil fuels and creating CO2 pollution are once again raising the costs of civilization, and people are rationally responding to these higher costs by cutting back in every area, one of which is raising very, very expensive children.
So if you want your “race” to proliferate, invest in research which will either reduce pollution and hence reduce our costs, or find a cheaper, less polluting way of growing food and providing energy.
The last Romans defending Constantinople against the gunpowder-using Hordes in 1453 probably didn’t see their situation in these terms, and the city eventually was overrun, like the rest of their empire.