- What does it mean to be intelligent?
- What do IQ tests measure?
- Racial differences in IQ scores
- Brainier than our grandparents
- There is more to intelligence than IQ
What does it mean to be intelligent?
Human beings pride themselves on being the most intelligent species on earth. But what does it mean to be intelligent? Most psychologists agree that abstract reasoning, problem solving, and the ability to acquire knowledge are all aspects of intelligence. There is less agreement on other factors, like mental speed, general knowledge, and creativity.
What do IQ tests measure?
Anyone who takes an intelligence test will be given an IQ (intelligence quotient) score. This score allows comparisons with people of the same age, on the assumption that 100 is the average IQ. Roughly 97% of people score somewhere between 70 and 130. But what do IQ tests measure? To some extent they measure our knowledge and vocabulary. But they also depend on the size of working memory, speed of processing, and an ability to choose appropriate strategies for solving particular problems.
Racial differences in IQ scores
IQ tests have been around for almost 100 years and have generated a good deal of controversy in that time. For example, it has been found that African Americans, as a group, have IQ scores roughly 10 to 15 points lower than White Americans. Many psychologists believe that cultural differences, like educational opportunities and familiarity with the demands of IQ tests, are responsible for these differences in IQ.
Brainier than our grandparents
One curious discovery seems to bear out this interpretation. It has been found that IQ scores in America improved by 20 to 30 points over the course of the 20th century. It does not make sense to believe that this increase is due to big leaps in inherited intelligence from one generation to another. Instead, it seems likely that successive generations have been better schooled in what it takes to do well on the tests.
There is more to intelligence than IQ
For many psychologists, it seems absurd to reduce the whole of human intelligence to the single score obtained on an IQ test. Instead, these psychologists emphasise multiple intelligences. Someone who may be skilled at learning languages may not be musically talented. What's more, our intelligence seems to vary according to how familiar we are with particular situations. One group of 10-year-old street vendors in Brazil, with very little schooling, were adept at working out what to charge for candy and were good at giving the right change. However, they did much worse when given identical addition and subtraction problems that were presented like traditional school tasks.