How The Flynn Effect Reveals Changes In IQ Over Time

In 2013, philosopher James Flynn got on stage and did a TED Talk about "the Flynn effect," a term coined after him in the controversial 1994 book "The Bell Curve," written by psychologist Richard Herrnstein and author Charles Murray. The name of Flynn's TED Talk — "Why our IQs are higher than our grandparents" — at once supports and refutes conventional wisdom. On one hand, some people are inclined to think, "Oh, those old farts didn't know anything; we're so much more advanced than them." Such is the arrogance of many generations, especially when directed toward ancient peoples, who are often conceptualized as being dumb enough to shove sticks in their nostrils as a hobby. And yet on the other hand, how many folks nowadays look around them and think, "Oh my God, everyone is so stupid; I hate people." What gives here? Is society smarter or dumber?

The truth is that on paper, folks have been getting steadily smarter for about 100 years. At least, as far as we measure and reckon one specific type of testable, psychologically quantifiable "intelligent quotient," aka IQ. Per, IQ scores have been on the rise since 1932 by about three points per decade. This means, as Flynn said in his TED Talk, that folks in the early 1900s would have scored a 70 by modern standards — an intellectual disability according to the American Association on Intellectual and Developmental Disabilities. But does that mean everyone alive is highly intellectually gifted? Hardly. New evidence, in fact, suggests that IQ scores are not only plateauing, but dropping.

The rise of fluid intelligence

Before going any further, we've got to look at the original reason why IQ scores climbed steadily for decades, and the specifics of the Flynn effect. As James Flynn describes in his TED Talk and sites like ScienceDirect summarize, increases in IQ scores are due to an overall increase in fluid intelligence or creative problem-solving abilities applied to novel or abstract situations. The opposite would be crystallized intelligence, the skilled use of learned information over time, as Verywell Mind explains. 

To illustrate, Flynn describes a doctor of 100 years ago versus a doctor of today. Modern professions have to incorporate more and more complex information. Society, on a whole, also depends on a greater degree of challenging intellectual tasks like those performed by engineers, technicians, programmers, teachers, lawyers, etc. To demonstrate, Flynn states that in 1900, only 3% of Americans practiced intellectually demanding work. Nowadays it's 35%. 

This might make it seem like crystallized intelligence — intelligence based on quantities of learned information — ought to be on the rise, but no. People aren't remembering more information. In fact, Flynn calls younger people an "ahistorical" generation. Rather, folks have gotten better at particular pieces of IQ tests, like Raven's Progressive Matrices test and the similarity subtest of the Wechsler Adult Intelligence Scale. This indicates an improvement in abstract thinking, hypothetical reasoning, and cognitive flexibility. This is why overall IQ scores have risen, a trend defined as the Flynn effect.

Dwindling problem-solving abilities

So then, what does it mean that IQ scores have decreased? explains that this is a recent occurrence, one visible only within the past few years. And lest you think that we're only talking about the U.S., this seems to be happening in many European countries as well. The current study, published in the journal Intelligence, analyzes data gathered over 12 years, from 2006 to 2018. Specifically, researchers used IQ scores collected from online personality tests taken by adults participating in the Synthetic Aperture Personality Assessment Project. Spatial abilities went up, but that's it. Verbal reasoning and numerical skills took a dive. The biggest drop happened amongst young people. 

If we take the Flynn effect as true and link rising IQ scores with increased fluid intelligence, then decreased IQ scores — very simply — means a drop in fluid intelligence. And if fluid intelligence is connected to environmental pressures caused by the need for complex problem-solving, the tackling of abstract issues, and so on, then it stands to reason that test-takers haven't had to contend with such intelligence-boosting pressures. Such speculation is beyond the scope of the study, but researchers do suggest that changes in educational systems may be to blame, as says. Time will tell, and maybe more data collection from a broader population. Let's just hope that the skills needed by the younger generation aren't called to bear in the meantime. Either that, or that the Flynn effect itself is in error.