Are Humans Getting Smarter or Less Intelligent?

We may pay a price for abstract thinking. 


Observe the behavior of shoppers in a long supermarket line or drivers snarled in traffic, and you can quickly become disillusioned about humanity and its collective IQ. Reality TV and websites like People of Walmart inflame this consideration. Lots of songs, both popular and underground, even utter the phrase “only stupid people are breeding.” Apparently, many of us can relate.

And yet, we’re better at technology today than in times past. Never before have we been more productive, better educated, or more technologically savvy. I had a teacher in high school who said that at the time Einstein was considering relativity, few people in the entire world were intelligent enough to understand it. But just a generation later, everyone had the theory in high school and understood it well, or at least well enough to pass the test.

So at different times and in different ways, we get competing impressions as to whether humanity collectively is getting smarter or less intelligent than before. Of course, the problem with personal experience is that it’s myopic or shortsighted. So what do studies tell us? What’s really going on here? Well, things get more complex and thornier moving forward, as they often do.

Howard Gardner (right) of Harvard, the father of the multiple intelligences theory. Getty Images.

First, there’s an argument even in terms of what intelligence is. Harvard psychologist Howard Gardner for instance, proposes multiple intelligences, which has been a staple in educational spheres for some years (.  Types include: verbal, logical-mathematical, visual-spacial, bodily-kinesthetic, musical, interpersonal (between people), intrapersonal (understanding your own feelings, thoughts, and beliefs), naturalist (understanding the outdoors), and existential intelligence (understanding the deeper questions of life).

Traditionally, vocabulary was used as a metric for intelligence. Research has shown that it’s highly correlated with IQ. Yet, according to a 2006 study, American’s vocabulary has been in swift decline since its peak, in the 1940’s. There is some controversy however, as vocabulary tests have been shown to hold an inherent cultural bias.   

If you look at IQ as the most vital metric, note that it’s been rising globally over time. But that doesn’t tell the whole story. In fact, there’s an interesting trend. IQ has been rising in developing countries, while it may be slowing in developed ones. In a 2015, King’s College London study, published in the journal Intelligence, psychologists wanted to know what shape the world IQ was in. Researchers spent over six decades conducting the study. In total, they collected the IQ scores of 200,000 people from 48 different countries. They found that global IQ has risen 20 points since 1950.

More abstract thinking is a sign of greater intelligence. Getty Images.

India and China saw the most gains. But developing countries in general have seen a rise, due to improved education and healthcare systems. What follows is known as the Flynn effect, named after political scientist James Flynn. In 1982, he predicted that rising living conditions would improve a people’s collective IQ. A number of studies support the Flynn effect. In the King’s College London study, IQ grew at a more rapidly in the developing world, while the pace slowed in US and other developed countries. Many developing nations may someday close the gap.

Another reason, the human brain continues to evolve toward ever more abstract thinking. Flynn quotes a study looking at rural Russian peasants. The researchers told them, "All bears are white where there is always snow; in Novaya Zemlya there is always snow; what color are the bears there?" Most had answered that since they had never been there, they would not know, or that they had only seen black bears.

Another example is that if you asked someone in the 19th century what a rabbit and a dog had in common, they wouldn’t be likely to point out that they’re both mammals or that they’re warm blooded. Instead, they may say something like, both are furry, or both are used by humans. Here, people rely more on their experiences in the real world, rather than abstract, logical or “scientific” reasoning. Flynn said that this change in our faculties illustrated, "Nothing less than a liberation of the human mind.”

Abstract reasoning helps use build impressive technology and understand how to use it. Getty Images.

Flynn wrote, “The scientific world-view, with its vocabulary, taxonomies, and detachment of logic and the hypothetical from concrete referents, has begun to permeate the minds of post-industrial people. This has paved the way for mass education on the university level and the emergence of an intellectual cadre without whom our present civilization would be inconceivable."

Will we ever reach a maximum in what humans can comprehend? Will environmental changes alter our mental landscape? What about those monumental changes about to be brought on by the second industrial revolution, the coming tidal wave of robots and AI? The answer to all of these is, no one knows.

One thought, older folks usually complain that young people lack “common sense.” When something is gained in nature or in life, something else is often lost as a result. Perhaps, as our thinking grows more abstract, we tend to lose the practical aspects of our faculties. Despite this, as each generation becomes more dissimilar than those past, their newly updated faculties help them to change the world in ever more dizzying, sophisticated, and delightful ways.

Why did humans become so intelligent in the first place? To find out, click here: 

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The study's senior author and Integrative Physiology Professor Christopher Lowry described this fat as "one of the main ingredients" in the "special sauce" that causes the beneficial effects of the bacterium.

The finding goes hand in hand with the "hygiene hypothesis," initially proposed in 1989 by the British scientist David Strachan. He maintained that our generally sterile modern world prevents children from being exposed to certain microorganisms, resulting in compromised immune systems and greater incidences of asthma and allergies.

Contemporary research fine-tuned the hypothesis, finding that not interacting with so-called "old friends" or helpful microbes in the soil and the environment, rather than the ones that cause illnesses, is what's detrimental. In particular, our mental health could be at stake.

"The idea is that as humans have moved away from farms and an agricultural or hunter-gatherer existence into cities, we have lost contact with organisms that served to regulate our immune system and suppress inappropriate inflammation," explained Lowry. "That has put us at higher risk for inflammatory disease and stress-related psychiatric disorders."

University of Colorado Boulder

Christopher Lowry

This is not the first study on the subject from Lowry, who published previous work showing the connection between being exposed to healthy bacteria and mental health. He found that being raised with animals and dust in a rural environment helps children develop more stress-proof immune systems. Such kids were also likely to be less at risk for mental illnesses than people living in the city without pets.

Lowry's other work also pointed out that the soil-based bacterium Mycobacterium vaccae acts like an antidepressant when injected into rodents. It alters their behavior and has lasting anti-inflammatory effects on the brain, according to the press release from the University of Colorado Boulder. Prolonged inflammation can lead to such stress-related disorders as PTSD.

The new study from Lowry and his team identified why that worked by pinpointing the specific fatty acid responsible. They showed that when the 10(Z)-hexadecenoic acid gets into cells, it works like a lock, attaching itself to the peroxisome proliferator-activated receptor (PPAR). This allows it to block a number of key pathways responsible for inflammation. Pre-treating the cells with the acid (or lipid) made them withstand inflammation better.

Lowry thinks this understanding can lead to creating a "stress vaccine" that can be given to people in high-stress jobs, like first responders or soldiers. The vaccine can prevent the psychological effects of stress.

What's more, this friendly bacterium is not the only potentially helpful organism we can find in soil.

"This is just one strain of one species of one type of bacterium that is found in the soil but there are millions of other strains in soils," said Lowry. "We are just beginning to see the tip of the iceberg in terms of identifying the mechanisms through which they have evolved to keep us healthy. It should inspire awe in all of us."

Check out the study published in the journal Psychopharmacology.