Is Race-and-IQ Research a Crime?

I.

On 20 March 2026, Counsellor Pierre Thiriar in the Antwerp Court of Appeals published an opinion piece in which he describes the writings of American philosopher Nathan Cofnas as punishable under criminal law:

When [Cofnas] states that genetic variants influencing intelligence may be unevenly distributed across populations and that this can explain differences in cognitive performance, this constitutes not merely a neutral hypothesis, but the empirical basis for a hierarchical view of humanity.

Cofnas is currently a postdoctoral researcher at the department of philosophy and moral sciences at Ghent University, and his position was already threatened by petitions and protests. Now the most radioactive topic in biology has been called criminal by a judge. So is Thiriar right?

First, some terms. When scholars use the term “individual differences,” they are referring to one person being taller, brighter, wittier etc than another. The term “group differences” refers to variation in average height, smarts, wit etc between—for example, older/younger, male/female, black/white groups of people. Then there are causes of measured differences at the individual or the group level. That’s four different levels of analysis, and conflating or confusing them leads to slop.

Unlike wit or kindness, both of which are socially valued traits, it’s rare to hear intelligence mentioned without someone becoming excited—and not always in a good way. But intelligence research is a scientific golden child. It survived the replication crisis that cratered psychology, and intelligence has the most explanatory power of any single trait in the whole of the human behavioural sciences. It has scientifically well-known properties. It is measurable in ways that are neither culture-free nor significantly biased, and its distribution is roughly a bell-shaped curve with a fat centre and narrow tails. In a large city, you will run across a few people who can figure out how to build a thirty-storey building and a few who find it hard to interpret a subway map. But most of the people you encounter will fall somewhere in between.

We underestimate the range of healthy normal variation in intelligence because in work and play we tend to mingle with others who are similar to ourselves. People with low cognitive abilities (and no known pathologies) are often diagnosed as having learning disabilities. But while low cognitive ability does constitute an impediment to learning, it is part of the normal distribution, just as a person who solves protein structures is also part of the normal distribution. Lower cognitive ability is not necessarily evidence of a disorder.

As well as being measurable and varying among individuals, intelligence is linked with many important outcomes, including health, income, educational achievement, and even (albeit weakly) life expectancy. These links are found in thousands of large-scale studies. The top-line is that a person’s intelligence can be measured reasonably well, humans vary a lot, and someone who is lucky with their intelligence is liable to be lucky with other good outcomes. This is the observed (measured or phenotypic) level of analysis concerning individual differences in intelligence and what is associated with such differences (their correlates).

Next let’s consider the causes of the wide variation in intelligence.