THREAD: 12 Things Everyone Should Know About IQ

1. IQ is one of the most heritable psychological traits – that is, individual differences in IQ are strongly associated with individual differences in genes (at least in fairly typical modern environments). https://t.co/3XxzW9bxLE

2. The heritability of IQ *increases* from childhood to adulthood. Meanwhile, the effect of the shared environment largely fades away. In other words, when it comes to IQ, nature becomes more important as we get older, nurture less. https://t.co/UqtS1lpw3n
3. IQ scores have been increasing for the last century or so, a phenomenon known as the Flynn effect. https://t.co/sCZvCst3hw (N ≈ 4 million)

(Note that the Flynn effect shows that IQ isn't 100% genetic; it doesn't show that it's 100% environmental.)
4. IQ predicts many important real world outcomes.

For example, though far from perfect, IQ is the single-best predictor of job performance we have – much better than Emotional Intelligence, the Big Five, Grit, etc. https://t.co/rKUgKDAAVx https://t.co/DWbVI8QSU3
5. Higher IQ is associated with a lower risk of death from most causes, including cardiovascular disease, respiratory disease, most forms of cancer, homicide, suicide, and accident. https://t.co/PJjGNyeQRA (N = 728,160)
6. Higher IQ is associated with lower rates of most forms of mental illness. https://t.co/0jX1og7xHV (N = 1,049,663)
7. More generally, IQ tests are among the most reliable, predictive measures in psychology – one of the field's crowning achievements. https://t.co/a9z9GPQYuD

If IQ isn't a valid concept, no concept in psychology is valid.
8. Despite this, many people are allergic to the concept of IQ. Ironically, this includes many intellectuals. https://t.co/ThPkVT8apc
9. Perhaps as a result, there's some evidence that researchers are less likely to publish studies showing a link between IQ and grades – the reverse of the usual publication bias for positive findings. https://t.co/gTiKmmarTB; although see https://t.co/sYEgBnaJkO
10. The antipathy to IQ is unfortunate. IQ predicts all things good. Interventions to boost IQ (such as salt iodization) could greatly enhance human well-being. https://t.co/LHVqClN2kE

Conversely, IQ-denial could cause real harm by stalling the development of such interventions.
11. IQ testing has other potential benefits as well. One of my favourite studies of the last few years found that universal IQ screening boosts the number of poor, female, and minority students in gifted education. https://t.co/5at8wNjKe8

Figure: https://t.co/fogF8GyO8Z
12. Last but not least, here's a list of ten common myths about IQ. https://t.co/DOTDWhMoyS HT @StuartJRitchie

More from Life

You May Also Like

First thread of the year because I have time during MCO. As requested, a thread on the gods and spirits of Malay folk religion. Some are indigenous, some are of Indian origin, some have Islamic


Before I begin, it might be worth explaining the Malay conception of the spirit world. At its deepest level, Malay religious belief is animist. All living beings and even certain objects are said to have a soul. Natural phenomena are either controlled by or personified as spirits

Although these beings had to be respected, not all of them were powerful enough to be considered gods. Offerings would be made to the spirits that had greater influence on human life. Spells and incantations would invoke their


Two known examples of such elemental spirits that had god-like status are Raja Angin (king of the wind) and Mambang Tali Arus (spirit of river currents). There were undoubtedly many more which have been lost to time

Contact with ancient India brought the influence of Hinduism and Buddhism to SEA. What we now call Hinduism similarly developed in India out of native animism and the more formal Vedic tradition. This can be seen in the multitude of sacred animals and location-specific Hindu gods