IQ deficit is not so much a direct argument against open borders as it is a support to other arguments. Specifically, it is claimed that:
- Under open borders, the average IQ (IQ is a proxy measure for intelligence) of immigrants entering a particular country would be lower than the average IQ of people already in the country. There are different views on whether IQ differences are genetic or cultural, and whether they will persist across generations. However, no specific assumptions about these questions need to be made to complete the argument.
- The lower average IQ of immigrants means that they are more likely to go on welfare, commit crime, have skills not adapted to the economy, suppress the wages of natives in low-skilled jobs, vote the wrong way, slow down technological progress by providing cheap labor, and more bad news.
The argument is complex and multifaceted and it is best here to link to some proponents who make the case eloquently:
- Cognitive Decline: The Irreducible Legacy of Open Borders on the La Griffe Du Lion website.
- Benthamite Libertarian Collectivists Wrong On Open Borders by ParaPundit.
- A Smart Solution to the Diversity Dilemma by Jason Richwine of the American Enterprise Institute (his article focuses on many other issues than IQ).
- The Negative Externalities of Immigration by Richard Hoste.
On the other hand, economist Garett Jones, who has extensively studied the relationship between IQ and economic growth, and agrees with the broad claim that average IQ is an important determinant of economic growth, believes that his research supports more open borders (though perhaps not completely open borders). He is one of the signatories to the open letter to the US President on immigration. On his homepage, he writes:
As a macroeconomist, I investigate both long-term economic growth and short-term business cycles. My current research explores why IQ and other cognitive skills appear to matter more for nations than for individuals.
For example: A two standard deviation rise in an individual person’s IQ predicts only about a 30% increase in her wage. But the same rise in a country’s average IQ score predicts a 700% increase in the average wage in that country. I want to understand why IQ appears to have such a large social multiplier.
The story is much the same for math and science scores: A person’s individual score predicts little about how she’ll do in the job market, but the richest and fastest-growing countries in the world tend to do much better on math and science tests. If the IQ multiplier is even half as large as it appears to be, then health, nutrition, and immigration policies in developing countries should be targeted at raising the average intelligence of the world’s poorest nations.
An even more important implication of my research is that low-skilled immigrants should be allowed to work in the world’s richest countries: Low-skilled immigrants have little or no net effect on the wages of the citizens of rich countries, but their lives massively improve when they are allowed to work in these countries.
Critical discussion of IQ deficit arguments from a non-restrictionist perspective
- Intelligence, international development, and immigration on the Open Borders blog develops in detail a case for open borders and charter cities based on existing research about IQ differences.
- Garett Jones responds to my intelligence post, a further development of why low IQ immigration may not lead to all the negative consequences feared by restrictionists.
- Immigration externalities, a blog post by Jason Collins where he lays out the key points of contention between competing hypotheses: the intermediating role of institutions, and the debate about whether it is the high IQ fraction or the low IQ fraction that is more predictive.
- In a Just World, an Econlog post by Bryan Caplan in which he argues that the low IQs of some immigrants should not be used to deny them their basic human rights.
Using IQ as an argument for immigration restrictions
- IQ and double counting the harms of immigration by Vipul Naik, October 14, 2012, on the Open Borders blog, arguing that IQ does not offer an additional reason to oppose immigration. An excerpt:
This brings me to the crux of my objection to the IQ deficit concern. If lower immigrant IQ raises concerns about higher immigrant crime rates or wrong political beliefs, then that should show up in the evidence on immigrant crime rates and political beliefs. If it does show up there, then great, score a point for restrictionists, and now that we’ve done that, what additional information does immigrants’ IQ deficit give us? By saying that immigrants commit crime and that restrictionists have a low IQ which means they would commit more crime, it seems like restrictionists are double counting crime.
- Against High-IQ Misanthropy by Byran Caplan, September 15, 2010, on EconLog, where he explains how comparative advantage addresses many of the economic worries about low IQ and addresses how compositional effects paint a misleading picture. He doesn’t specifically address immigration, but it’s the subtext of his blog post.
- IQ With Conscience by Byran Caplan, April 18, 2017, on EconLog. Not specifically dealing with migration, the blog post argues that IQ realism should not entail draconian policy.
- IQ and Immigration: Only a Slight Caricature, by Bryan Caplan, May 6, 2010, on EconLog, where he writes:
Mr. Human Biodiversity: The average IQ of immigrants from Mexico is 11 points less than ours. Therefore, let’s hunt them down like animals and cast them back into the fiery chasm from whence they came!
Dr. Mainstream Intellectual: Only a monster like you would say such a horrible thing about their IQs!
What he’s saying, albeit indirectly, is that even if the IQ deficit is real, this is not a sufficient justification for immigration restrictions given the strong case in favor of open borders. Keyhole solutions would be more appropriate. Caplan is also chiding mainstream intellectuals for getting outraged about the statement on IQ differences (which ultimately is a factual assertion that can be proved or disproved by looking at the evidence) rather than tackling the real monstrosity: using IQ differences as a basis for immigration restrictions.
- In a quote discussing IQ and immigration issues on Slate, noted restrictionist economist George Borjas said:
In fact, as I know I told Jason early on since I’ve long believed this, I don’t find the IQ academic work all that interesting. Economic outcomes and IQ are only weakly related, and IQ only measures one kind of ability. I’ve been lucky to have met many high-IQ people in academia who are total losers, and many smart, but not super-smart people, who are incredibly successful because of persistence, motivation, etc. So I just think that, on the whole, the focus on IQ is a bit misguided.
IQ researchers’ views and influence on the immigration debate
- Did IQ Research Cause U.S. Immigration Restriction?, a blog post by Bryan Caplan.
- IQ researchers’ views of immigration, a systematic tabulation on the views held by various IQ researchers regarding immigration.