March 6, 2019


Thomas J. Bollyky
1777 F Street, NW
Washington, DC 20006

Dear Dr. Bollyky,
You may not remember me, but I was enjoying your recent talk at the AAAS and passed you a DVD on the relationship between kinship and fertility.  I would guess you have yet to make occasion to spend an afternoon in its perusal, but for this letter I shall assume you know it all by heart.  If you have discarded it, I’d be happy to replace it.  I have just finished Plagues and the Paradox of Progress and shall soon start the book you recommended, The Wizard and the Prophet

It was heartwarming to read about so many times when deliberate human effort has led to gratifying results.  It could make you think there are some good people in the world.  Unfortunately, this is in jarring contrast with my own personal experience. 

F’rinstance, we know that in order to become a member of the bureaucracy in historical China, one had to be a eunuch.  This strategy was brilliantly successful, and the Chinese culture has been unmatched in its durability.  But suppose somebody said, “Sure you can all migrate to this country, but we’ll have to sterilize you and all your children first.”  I think we can agree that this would be a loathsome proposition.  Now suppose the arrangement were being made without the knowledge of the would-be immigrant.  The word “evil” now comes to mind; but lest we be hasty, there might be some countervailing consideration that preempted all normal moral rules; not that I can suggest one.  But now, suppose somebody who is a recognized expert in such things, say a scientist in his or her own specialty, has this secret program pointed out and is free in perfect safety to squawk.  Failing to do so seems to me to qualify for evil and hypocrisy at the same time.  This has, with the exception of Robin Fox, been the universal response.  These superficially decent professionals have shrugged me off without a word.  Having seen the DVD, you know there is absolutely no doubt that a random mating population bigger than say a couple thousand will die out from outbreeding over several generations. 

Consider a man who walks from Honduras to LA.  The most important hour is not when he enters the sanctuary nor when he enters the US.  It is when he leaves his own village, because there is absolutely no other place on earth where he and his offspring are going to be able to find the few mating chances with a long-term future. 

You say more than once that if death rates are high women will choose to have more babies in order to have some survive.  I remember the lecture at Harvard Medical school when the prof said, “Look.  Children are not tires.  When a couple loses their only child, it is terrible.  But when a couple loses one of four children, it is just as terrible; these are children and they matter just as much.  Don’t go thinking, ‘Ah, but they have a spare child.’  That works really well for tires.”  Before I reject the man’s experience, I’m going to need a lot of evidence. 

As you kept returning to the spare tire theory of fertility, I began to try to reconcile it with the Danish and Icelandic data that indicate kinship issues alone determine fertility; income and education mean nothing.  Maybe when a woman lost a child that kinship dictated she should have kept, she might have replaced it.  But if that happened to any significant degree it should have shown up in the UN numbers showing the trajectory of fertility over time (and incidentally proving that race is totally irrelevant where it counts). 

As I studied your brilliant book, something burbled to the surface.  Before infectious diseases rose to their great importance in Africa, the population stayed low and stable.  I read recently and lost, cuss my picture, an article talking about skulls that antedated the rise of agriculture.  Most, yes most, had been fractured during (usually at the end of) life.  Yep, all those years and we murdered each other at a rate Spanish flu could only approximate.  This same pattern – kill all strangers on sight – has been reflected in Conrad’s Heart of Darkness, the recruitment of boys by rebels in Sierra Leone and in natives of New Guinea.  Indeed, people have been so awful that colonization by European powers that demanded a monopoly on violence resulted in a population explosion.  The fall in early mortality would not come for some time.  Even slavery was kind of an improvement.  People who would normally have been slaughtered were sold when a ship with a hold full of barrels of Massachusetts rum sailed in. 

So after about 30 years of abject failure to warn people that failure to marry kin will kill us all, I begin to wonder whether I shall ever turn them.  Like mice we mate according to status and violence.  It has been our regular undoing and is slated to wipe us right out. 

Of course, our high-tech civilization will go first.  According to the UN numbers, the poorest nations should now have a fertility about 3.5 children per woman, dropping to below replacement by 2045.  Your projection for 2050 does not persuade me.  Those sub-Saharan countries look like our last best hope for saving humanity from extinction.  We need to help them, but migration is murder.  If you ask me, I say we give everybody in the world a dollar a day.  Might cost a couple or three trillion.  Cheaper than the military, eh what?  Easy to do directly over the internet; it’s sort of the logical extreme of local decision about where to put aid money.  And it would massively boost our own economy as those dollars come home to roost.  They can figure out how they’ll manage when we are gone.

I’m still despondent but deeply in your debt for all your hard work making this information available.


M. Linton Herbert MD

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