How much does IQ have to do with success?

What determines a person's intelligence? Many people take it for granted that the bigger the brain, the smarter the person, but anatomists have found that this is not true. Gauss, known as the "Prince of Mathematics," had a brain weight of 1,492 grams, about the same as that of an average person. The brains of linguist Hermann, number theorist Dirichlet, and mineralogist Hausmann have also been studied after death. Their brains were of normal weight and their brain sulci were nothing special.

After Einstein's death, his brain was stolen by Thomas, the doctor on duty, and cut into 240 pieces and hidden away. It was not rediscovered until more than 20 years later. Einstein's brain weighed 1,230 grams, which was lighter than that of an average person. The number of glial cells in certain brain regions was higher than that of normal people, which may be related to the increased metabolic activity of neurons. Einstein's inferior parietal lobe was more developed than that of an average person, which may be related to mathematical thinking and spatial cognition.

There is a certain correlation between brain structure and intelligence, but there is currently no clear standard to judge a person's intelligence or talent based on brain structure.

The most reliable way to measure intelligence is with an intelligence scale. The world's first IQ measurement took place in 1905, using an intelligence scale developed by French psychologist Binet Simon. Since the development of IQ measurement, there are already dozens of different scales. The most widely used one is the intelligence scale developed by American psychologist Wechsler. It includes 11 items, namely common sense, understanding, arithmetic, similarity, memory, words, images, building blocks, arrangement, puzzles, and symbols. It takes about 1 hour to complete the entire test.

The IQ measurement sets the average IQ of the main subjects as 100, and evaluates the IQ of each subject on this basis. According to statistics, half of the people have an IQ between 90 and 110, of which 25% are between 90 and 100 and 100 and 110, 14.5% are between 110 and 120, 7% are between 120 and 130, 3% are between 130 and 140, and 0.5% are above 140, and 25% are below 90. There is no obvious difference in IQ between people of different genders, constellations, and blood types, and IQ is not entirely determined by nature, but acquired training is equally important.

Are people with high IQs more successful? A US researcher conducted a survey on the relationship between IQ and wealth on 7,403 subjects and found that for every 1 point increase in IQ, the average annual income increased by $426. However, there is no significant linear relationship between IQ and wealth, but rather a complex quadratic function relationship, which means that many people with high IQs are "too smart for their own good". Researchers believe that IQ is not the main factor in determining economic success. Various psychological factors such as risk tolerance, ability to delay gratification, and personal motivation level are all important factors affecting economic success. To use the more popular saying now, success is determined by 20% IQ and 80% EQ.

Although IQ is not a panacea, people still hope to become smarter. In the science fiction movie "Lucy", the heroine Lucy took a certain drug, and her brain potential development increased from 10% to 100%. With the increase of IQ, she changed from a lamb to be slaughtered by the underworld to a "super body" who can control other people's minds. Unfortunately, there is no such drug in reality. The "nootropics" on the market are used for patients with memory loss and have side effects.

The contestants of the TV show "The Brain" have good memory, good observation, and fast calculation... These intelligences that can be used for performance only account for a small part of human intelligence and can be easily replaced by artificial intelligence. In 1983, Gardner, a psychologist at the Harvard Graduate School of Education, proposed the theory of multiple intelligences. He believes that intelligence is the ability of people to solve problems and create in specific situations. Everyone has eight main types of intelligence: language-text intelligence, logical-mathematical intelligence, spatial intelligence, motor intelligence, musical intelligence, interpersonal intelligence, introspective intelligence, and natural observation intelligence. This theory emphasizes the comprehensive cultivation of multiple intelligences, and also advocates helping students find careers and hobbies that suit their intelligence characteristics, and guiding them to eagerly pursue their inner interests.

Everyone has a unique brain. Instead of envying others' "high IQ" or "talent", it is better to seriously develop your own inner treasures. This requires people to have dreams, continue learning, improve cognition, and have the courage to practice.

(The author is an associate professor at Central China Normal University and a member of the Chinese Society for Neuroscience)