Well, then I'm puzzled why you didn't reply to these misguided assertions.

In any case, the paper you cite may well be correct point-by-point, but on the whole, it's a lawyerly argument that tries to overwhelm and misguide the readers by amassing a pile of hand-picked one-way evidence that will dazzle them and make them lose sight of the overall balance of evidence. As I wrote in that earlier comment thread in response to similar points:

As for heritability studies, you are certainly right that there is a lot of shoddy work, and by necessity they make a whole lot of wildly simplifying assumptions. If there existed only a handful of such studies, one would be well advised not to take them very seriously. However, the amount of data that has been gathered in recent decades is just too overwhelming to dismiss, especially taking into account that often there have been considerable ideological incentives to support the opposite conclusions.


Sadly there are many blind spots here where groupthink rules, and people will just happily downvote anybody who has a different opinion. They are not worth replying to. I see the downvote brigade found this thread as well.

1RichardKennaway8yPiling up shoddy evidence does not make good evidence. (And it still doesn't if you -- that's the impersonal "you", not you in particular -- call it "Bayesian evidence".) There are considerable ideological incentives on both sides. The Sesardic book you recommended is in my university library, but when I went to look at it, I found at least a shelf-foot of books on the subject, some (I could tell just from the authors' names) on one side, some on the other. So I didn't bother looking any further and left all the books there. I could read Sesardic saying what you say he says, but then I could read Kamin arguing the opposite, and in that situation, to form a view of my own with any real basis I'd have to research the subject enough to write a book of my own. I have other things to do. Such is the nature of controversies: they cannot be settled by saying "read this book". One observation though, that I haven't seen made on either side. Failing to find strong genetic causes for something does not imply that it's the environment; failing to find strong environmental causes does not imply that it's the genes; failing to find either does not imply that it's the interaction of genes and environment. I believe I've seen (but no cites) all three wrong arguments being made from time to time. All that failing to find the causes implies is that we have failed to find the causes.

Review: Selfish Reasons to Have More Kids

by jsalvatier 3 min read29th May 2012260 comments








  • No effect on intelligence.


  • Possibly a small effect on sexual orientation.

So how do adoption studies lead to these conclusions?




If parenting doesn’t matter, what does?




Don’t be a tiger parent




Have more kids


Other Topics


Here are some other topics Caplan discusses in his book:


What parts should I read?


Criticisms of Selfish Reason To Have More Kids

