Worldwide IQ in Decline

This chart was derived from a study at the University of Hartford (Connecticut). While people have tired desperately to come up with all sorts of hypotheses related to pollution and global warming (yes, global warming), the answer is quite simple to anyone who has taken even an introductory course in statistics.

Fertility rates are inversely proportional to intelligence. That is, the more intelligent you and your spouse are, the fewer children you are likely to have. Rudimentary statistics tells you that the average intelligence of the entire population will fall.




Now, compounding this are two additional factors:

1. One of the balances to the fertility rate problems has been the Darwinian one -- low IQ is not a survival characteristic. That is, peoples with low IQ tend to have lower life expectancies. Therefore they reproduced at lower rates. Modern science and technology has intervened to reduce the effects of life-threatening disease -- from malaria to Ebola.

2. As Charles Murray pointed out in Coming Apart, the tendencies for like to marry like are increasing. Since a child’s IQ is highly correlated to that of his parents, this means that instead of reverting to the mean, IQ is becoming more bi-modal – that is, greater concentrations at high levels (low fertility)  and low levels (high fertility).

All of this suggests strongly that we should expect the decline of the last 50 years to continue. Not a particularly positive trend in light of the fact that technology is also rapidly eliminating the sorts of jobs that people with lower intelligence can do.