Humanity is constantly improving

LABORATORY: Stagnant Flynn EffectPeople are getting dumber

Is humanity getting more and more stupid? Young people in the Botanical Garden of Tübingen don't seem to be worried about that. Most of them laugh, which is supposed to make it clear that at least they don't perceive the question as a problem - even if there might be truth in it.

"Right now, I'd rather say that humanity gets a little dumber when you watch the news."

"So if you look at the USA - Trump's following, which is not really getting any smaller. I don't know if you can always associate that with this IQ."

"Well, I'm at university now, so it seems to me that you are getting smarter - but I'm not entirely sure either!"

Inferential thinking as an advantage

In fact, IQ is not a guide to how people behave or what decisions they make.

Intelligence tests simply assess the ability to think logically, explains the psychologist Professor Elsbeth Stern from the Swiss Federal Institute of Technology in Zurich.

"Intelligence is primarily the ability to reasonably think and to process information efficiently. And you need it above all when you have to solve complex tasks. And then you have people who can do it more efficiently, who are better able to keep more information in parallel who then have an advantage. "

To assess logical reasoning, intelligence tests have questions like: 2,4,6,8 - what is the next number?

In this very simple example: the 10th

Or: forest is to trees as meadow is to greenery - grasses - vastness - flowers?

"Grass - I don't know - grass - I would have said flower spontaneously."

Correct would be: grasses.

Education trains the brain

The average IQ rose steadily in the developed countries of the western world in the 20th century. "Flynn Effect" - it is called after the researcher who first described the phenomenon, James Robert Flynn.

According to Elsbeth Stern, the main reason for this was education: in the course of the 20th century, the children went to school longer and longer. As a result, her brain was trained better.

"So you only develop intelligence when it is also required when you are given demanding tasks. Then you learn better reasoning and how to process information more efficiently."

But at some point it was over with the increase in intelligence. Scientists noticed that the IQ began to stagnate - at a different point in time depending on the country.

"In western countries, the environmental conditions, medicine, schooling and extracurricular learning opportunities have improved so much that people have had more and more opportunities to develop the intelligence provided for in their genes. And this is where the climax has been reached. "

It's not the genes

The economist Dr. Bernt Bratsberg and the political scientist Dr. In their study, Ole Rogeberg from the Frisch Center in Oslo compared the data of over 800,000 Norwegian men who were born between 1962 and 1991 and who had to take a standardized intelligence test when they were drafted into the military. The result: The IQ not only stagnated. He went back from the 1975 birth cohort.

Ole Rogeberg thinks this is worrying.

"The results that people get on an intelligence test are very important. Because in another study last year we found that people with low IQ are four times more likely to die than people with good results."

Because the intelligence that a person can develop is determined by their genes, some scientists previously believed that stagnation or decline in intelligence must also be due to genetic material. There was the thesis that especially people with low intelligence have many children - and that this could have led to a decrease in intelligence in the long term.

Bratsberg and Rogeberg have now refuted this thesis. Because in their study they also examined how siblings performed in the intelligence tests. So people with very similar genes. The result: The IQ of siblings in Norway also fell from birth cohort 1975 onwards.

"That means that it is not the genes, but some environmental influence that must have influenced the intelligence. And that depends on the year in which the children were born. It is not about genes - otherwise there would be no differences between children who have the same parents . "

Possible influences: media consumption and diet

Changes in the education system, increased media consumption, changes in diet - there are many factors that can influence IQ. Professor Elsbeth Stern from ETH Zurich suspects that education could play a decisive role. But whatever led to the worse results, there was nothing to be concerned about.

"And you shouldn't over-dramatize it. The changes are in a few points - so the turning point doesn't mean: By then everyone has become smarter - and then things went downhill. Rather, there were just such slight changes and they show up in this one Sample, particularly clear in the Norwegian sample. "