Won’t the Amish or some other high-fertility, perhaps religious, sub-population expand to be as many as we need? For several reasons, no.
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First, fertility in a high-fertility sub-group would have to be high enough (certainly above two, for example). We’ve already seen above that the “high fertility” of high fertility subgroups has been declining over the decades. High fertility used to mean 6 children per woman. Now it means 2.5. Before long, it may mean 1.8. Second, the children of high-fertility parents would have to be very likely to remain in their high-fertility cultural group.
I grew up in a small-town homeschooling community where large families were fairly normal, but many of the children did not go on to have many children, or homeschool their own children.
In contrast to that, I am now a member of a church where 4 children is considered a small family, and 12 children is considered a large family.
Many of the families are second-generation, and one of the topics of conversation is how to pass on a worldview that involves passing on that worldview recursively through the generations.
We’re not Amish, but the Amish do seem to be doing a good job of this – per https://en.wikipedia.org/wiki/Amish#Population_and_distribution their numbers have been impressively consistent over the years. I don’t know why the authors think that their next 100 years of growth would change from the last 100.
Now, it’s going to take a while for their numbers to affect the global population. But it doesn’t seem crazy to me that in a few centuries the world’s population will be comparably large, and even more dominated by a few Islamic and Christian sects than it is now.
Thanks for the information! I was thinking in a similar direction:
Just like the Amish culture has emerged from the standard population, a new “Amish-like” culture may emerge again, or perhaps a new “super-Amish” culture may emerge from the Amish. There is no law of nature saying that there will be exactly one Amish-like culture ever, and once its fertility declines, it is all over.
And generally, I think that the exponential curve drives people to hysterical predictions, because it ends with a disaster either way—exponent > 1 means we overpopulate and starve to death, but exponent < 1 means we go extinct, and exponent = 1 (with infinitely many decimal places) is statistically unlikely. So by that logic we are doomed no matter what happens.
I take issue with the authors here:
I grew up in a small-town homeschooling community where large families were fairly normal, but many of the children did not go on to have many children, or homeschool their own children.
In contrast to that, I am now a member of a church where 4 children is considered a small family, and 12 children is considered a large family.
Many of the families are second-generation, and one of the topics of conversation is how to pass on a worldview that involves passing on that worldview recursively through the generations.
We’re not Amish, but the Amish do seem to be doing a good job of this – per https://en.wikipedia.org/wiki/Amish#Population_and_distribution their numbers have been impressively consistent over the years. I don’t know why the authors think that their next 100 years of growth would change from the last 100.
Now, it’s going to take a while for their numbers to affect the global population. But it doesn’t seem crazy to me that in a few centuries the world’s population will be comparably large, and even more dominated by a few Islamic and Christian sects than it is now.
Thanks for the information! I was thinking in a similar direction:
Just like the Amish culture has emerged from the standard population, a new “Amish-like” culture may emerge again, or perhaps a new “super-Amish” culture may emerge from the Amish. There is no law of nature saying that there will be exactly one Amish-like culture ever, and once its fertility declines, it is all over.
And generally, I think that the exponential curve drives people to hysterical predictions, because it ends with a disaster either way—exponent > 1 means we overpopulate and starve to death, but exponent < 1 means we go extinct, and exponent = 1 (with infinitely many decimal places) is statistically unlikely. So by that logic we are doomed no matter what happens.