American IQ scores have rapidly dropped, proving the 'Reverse Flynn effect'

Honest question that keeps bothering me.

In the absence of reasonably strong natural selection pressure to select for IQ, how could IQ not be falling over time?

It is not. IQ doesn’t measure a kind of intelligence which inherits, and is subject to natural selection (there is even a debate whether such intelligence exists; or at least is of any significant between individuals).

IQ at best measures something that correlates with SAT. And with better education, less exposure to damaging pollutants, etc. it should always be on the rise (as demonstrated by the Flynn effect; an effect which this poor paper desperately tries to refute).

IQ research has always been about proving the superiority of one race over others, this superiority doesn’t exist, but that doesn’t stop these pseudo-scientist from trying. They bend the definition of “intelligence” and device test batteries (and in this case, interpret test battery) in skewed and bias ways to manipulate results like these. Regrettably media outlets like the Popular Mechanics and lifestyle journalists like Tim Newcomb take these researchers at their words and publish their results, despite their results pretty much being lies.

The heritability of IQ is very well established, usually estimated in the 50-80% range. You are fighting an uphill battle here because even if people haven’t seen the scientific evidence this effect is so strong that virtually everybody has seen anecdotal evidence of high IQ parents having high IQ children, but just seem to assert a very heterodox and counter-intuitive position without further elaboration.

It is incredibly arguable if during an obesity crisis if population wide health is actually improving and if population wide health isn’t improving that could certainly contribute to lower IQ. We’re also seeing population wide declines of health in other ways like sperm count. Food is becoming less nutritious as soil depletes. Our fish stocks being about to collapse is going to be another hit against brain health as omega 3s will become rarer in the diet.

I’m not fighting an uphill battle. Ever since The Bell Curve came out, there has been a slow but steady distancing of both psychological research and policy makers from the whole field of IQ research. Modern psychology couldn’t care less about on the heritability factor of IQ, and most policy makers don’t want to touch it with a 10 foot pole. Heck the SAT has even been renamed as they don’t want to be affiliated with anything resembling IQ any more.

The heritability of IQ is only well established within true believers of a pseudo-science tightly linked with the eugenics movement. Most psychologists today believe that the supposed heritability was observed because of bias within the research. And given the people who were doing these research in the 1970s and the 1980s, and their motivation for doing those, there is no question on what these biases were. Some of the researchers went so went quite far in bending the data such that it would fit their narrow—and racist—world view. They tried really hard to define intelligence such that it would make rich white people smarter, they were regrettably successful for far to long, but ultimately failed.

Your anecdotal evidence of high IQ parents (ugh!) having high IQ children is the same anecdotal evidence that sociologists have been describing for decades that high SES parents have high SES children, and is the main reason for why parents with high SAT scores are likely to have children with high SAT scores.

What IQ researchers discovered was basically the same thing that Marx described in 1867, class, however the eugenics were no communists, and instead of providing the simpler explanation, that society rewards the ruling elite, and wealth inherits, the eugenics went all conspiratorial and blamed other races for their perceived decline in society.

Have these heritability studies been done in other countries where some of these biases might not exist?

There aren't that many, but here's one:

https://www.sciencedirect.com/science/article/abs/pii/S01602...

It's a twin study. Here's a quote: "Mean IQ scores were modestly higher among those from higher SES backgrounds, but the magnitude of genetic influences on IQ was uniformly high across the range of SES." SES means "socio-economic status".

Honestly, the evidence for heritability of IQ is very strong. Arguing against it, in my opinion, borders on arguing that vaccines don't work. I actually understand why people do it (there's a lot of very bad history in how IQ data has been used). But I just think it's more important in the long run to tell the truth and find solutions based on the truth.

> Arguing against it, in my opinion, borders on arguing that vaccines don't work.

This is an interesting opinion. So vaccine research has produced a number of successful trials, the research is keeps furthering more knowledge, we develop new techniques, new models, new successful predictions, and new products which yield more successful trials. I consider this a healthy field of science and engineering.

Now how does IQ research fair next to vaccine research. The first IQ test was authored in 1908, not to measure intelligence among populations, but to assess learning disability. Since then IQ researchers have been trying to prove that IQ differences exists among populations. They have created and standardized new types of IQ tests that are supposed to show this difference exists. They have spent the past 100 years doing this, using fancy statistical methods, but have so far failed to convince the other fields of science (especially other fields within psychology), nor have they convinced policy makers (though they were pretty close during the eugenics craze). They have no theory of behavior other then this hypothetical general intelligence. They have no models that predict behavior, they have no products other then their intelligence tests, the tests are constantly criticized, have no successful double blind trials to show for them selves. The techniques are the same as in the 1970s, just plain old pen and paper tests with some factor analysis to spot the correlation they were hoping to spot (some would say, preconditioned or biased to spot).

If I were to be generous I would categorize IQ research among string theory as a scientific dead end. They had a theory, it didn’t go anywhere, and now the rest of the field has moved on. However given the history of IQ research and their ties to the eugenics movement, I’m not gonna give them this benefits. I believe IQ research, with the exception of Alfred Binet him self, was always about putting people in racial categories to show that one group was superior to another, with a made up construct they call intelligence.

IQ testing has numerous applications. For example:

* SAT tests largely amount to IQ tests and are used extensively for college admissions in the US. College degrees from top US universities remain the most sought after degrees in the world.

* Magnet schools in urban areas regularly utilize IQ tests or their equivalents to elevate students into advanced coursework. This enables students to rise above their socioeconomic status.

* European secondary schools regularly use tests that correlate with IQ tests to track students into programs leading to universities versus technical schools. These tests help coordinate society and deploy human capital where it is most needed.

* Even the US military uses IQ tests to avoid accepting recruits who don't meet a certain standard. This aids in ensuring the security of western nations.

IQ testing could be used in additional areas, such as:

* Encouraging higher IQ parents to have more children through subsidies, thereby increasing the likelihood of future technological innovations assisting all mankind.

* Assisting in identifying individuals who need more support from society.

* Better understanding the causes behind social ills like poverty, drug addiction, homelessness and the like. Understanding that an individual's IQ is a stronger determinant of economic outcome than other variables, such as race, is a step toward a society with more solidarity and less friction.

I appreciate that you have a bias against intelligence testing, and I understand its genesis (your mention of the "eugenics craze" makes that clear). I'm suggesting society aim toward an enlightened view of these things where people's IQs don't identify them as "greater" or "lesser". Wishing IQ away is unlikely to work, particularly in a world about to experience the arrival of super-intelligent AI systems.