September 8, 2013
to be posted on if there is no objection
Jimmy Simmons c/o

Dear Mr. Simmons:
I do miss the moral clarity of youth so I thank you greatly for working out a meeting with an organization with which your own has been in so much tension at times.  That was a good thing.

When dealing with people with whom one has reason to think there is a deep lack of sympathy there are two approaches: Listen very carefully or not at all.  I beg you to think about this carefully.  Alas I do not offer moral clarity. 

First let me define “larger family” as all relatives closer than maybe seventh or eighth cousins.  The evidence leads me to believe that those who fail to marry within the “larger family” pay a fertility price.  My evidence is at
One you get out past ninth cousin it doesn’t matter what the relationship is; half way across town might as well be the far side of the planet. 

I do not know exactly how it plays out, but my impression is that if you start with an optimally inbred population such as let’s say colonial New England or the pioneers, and start a program in which everybody marries outside of the “larger family” fertility will fall by about a half every generation.  If you start with families of sixteen – and the pioneers came close – by the fourth or fifth generation this looks very grim.  Indeed there is a hint in the evidence that the rate eventually simply goes to zero. 

As I said, that’s only a guess.  You can look at the evidence as well as I can.  I’ll attach a paper that shows something like this in fruit flies. 

As you can well imagine, people find it hard to grasp that tenth cousins and thousandth cousins are the same in this regard so of course they take the easy way out and don’t listen at all.  My friends think they smell racism, and that ends it.  Of course I oversimplify.  What if somebody who’s expected fertility is two marries somebody who is outside “larger family” and whose expected fertility is eight?  I don’t know.  Maybe it’s somewhere in between. 

Most people say it’s “choice.”  That has been specifically examined in one of the two Danish papers and they found that once issues of kinship were excluded neither education nor income had any effect on number of children at all.  Fruit flies don’t get paychecks or educations, so it doesn’t apply there either.  Of course Danes and laboratory fruit flies lead secure lives; maybe under extreme circumstances choice does play a part. 

I think this is terribly important.  The rich world is undergoing demographic collapse.  That would be all right with me if they understood why.  They, we, don’t.   Knowing and remaining silent seems to me to be, well, evil.  But since that includes all my friends and relations, I have learned to be tolerant.  Moral clarity is not the only thing people need. 

Let me know what you think, if you would be so kind.


Linton Herbert 

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