Intelligence
Created | Updated Jan 28, 2002
Intelligence is something we all think we have but which actually is all too lacking in many of us. Intelligence is also something thats still quite mysterious and not really understood.
A common sense view of intelligence is that its how knowledgeable and intellectual a person is. For example if someone you know often makes statements such as: 'Yo man, I gonna hit the road and gonna go to that them shops for some beers and stuff' you may assume he is an imbecile. If on the other hand he regularly makes remarks such as 'A non-zero cosmological constant in General Relativity has effects similiar to the zero-point quantum vacuum energy' you may think hes a raving genius!
This is not neccessarily the case because one of the most popular ways in which psychologists have tried to define intelligence is that its a capacity for general learning. It measures a potential learning ability not how knowledgeable one is
The first intelligence tests - Binet and Terman
In 1904 the French minister of education wanted to find a way to determine school children with special needs. Alfred Binet was the one given the job of selection principles and it is he that devised the first proper tests to try to actually measure a persons 'intelligence'. The term IQ was coined by Lewis Terman of Stanford University in 1916. Terman had revised Binets tests and designed a test he called the Standard-Binet, which measured the 'IQ'
A theory of general intelligence - Spearman and Burt
It was the Englishman Charles Spearman who between 1904-1927 argued for the existance of a general factor of intelligence, which he called g. Sir Cyril Burt was one of Spearman's students, but he unfortunitly bought disrepute to the field by apparently making up data on 'twin studies' which was supposed to prove that intelligence is largely genetic
An alternative view - Thurstone
A guy named Louis Thurstone (1938) proposed one of the first theories of multiple intelligence. Rather than a single general factor of intelligence, g, argued Thurstone, there are a number of different intelligences that are largely independant of one another. He suggested 7 factors which he referred to as 'primary mental abilities'
Sternberg's Theory
Psychologist Robert Sternberg has proposed what he calles his 'triarchic' theory of intelligence in which intelligence is regarded as consisting of 3 main componants which work together. These componants he calls the practical, the analytic and the creative. The practical componant means special knowledge and skills for a given situation, the creative componant is the ability to generate new and original ideas and the analytic componant is the ability to plan and reason.
Gardner's Theory Of Multiple Intelligences
In the 80's a man named Gardner put forward some new theories about intelligence. His is a theory of multiple intelligences.
Gardner came up with 7 general types of intelligence:
Linguistic: Dealing with words and their meanings. Language stuff. Important for poets and writers! Verbal skills were part of what was measured by traditional IQ tests
Spatial: The ability to visualise things and manipulate them in your head. Architects and chess players seem to excel in this skill
Logical-mathematical: Part of traditional IQ tests. The ability to reason things out and to draw correct conclusions about things. Mathematicians and scientists will need this skill.
Musical: The ability to compose music and to understand it - pitch (notes), timber (the sounds of the different instruments) and rhythm are the main aspects of music. Important for musicians obviously!
Interpersonal: Social skills - the ability to understand and get along well with people in general. Useful for politicians, leaders and those working in the social sciences
Intra-personal: The ability to understand and control ones inner self. Motivators and coaches excel here
Body-kinesthetic: The ability to co-ordinate ones physical actions and to understand ones own body. Dancers and athletes would rate highly here
What is IQ?
IQ can be defined in two different ways:
Ratio IQ: IQ as an 'Intelligence Quotient' A persons mental age devided by their chronological age and multiplied by 100. For instance a person who was 10 years old but had the mind of a 20 year old would have an IQ of 20/10 x 100 or 200. Children usually have their IQ defined this way.
Deviation IQ: A measure of how rare a person with a certain intelligence is. The deviation IQ's are defined to obey a perfectly normal distribution (thats the famous bell-shaped curve showing the frequencies of the IQ's). This is the modern IQ definition for adults.
There are different deviation IQ scales because different tests have different numbers for whats called the mean, and standard deviation. Confused? Don't worry. The point is that all the different tests can be converted to the same deviation IQ scale for comparison, which by convention has a mean of 100 and a standard deviation of 16. To avoid confusion thats the scale we'll talk about here when we refer to IQ
The average IQ is in the range 90-110. Half the population falls into this really narrow range.
An IQ of 133 or better indicates a gifted person, and qualifies you to join
Mensa
, the society for the very intelligent. Only 1 in 50 people have an IQ this high or better.
An IQ of 150 or better indicates a potential genius
IQ Tests
We try to measure IQ with an 'Intelligence Test' The traditional form of IQ test consists of variations on the Stanford-Binet tests. These tests usually have a mix of verbal, logical and numerial questions, and are supposedly measuring g, a general form of intelligence.
Other types of intelligence test are called aptitude tests and are used to guage skills in various academic areas - most well known are the Wechsler Scales WAIS and WISC, and the infamous Scholastic Aptitude Test (SAT)
There are also types of test that have been developed to try to eliminate cultural or educational biases. These consist mainly of questions asking one to identify visual patterns. Ravens Progressive Matrics is a well known one of this type
There are loads of links to online tests at
The Uncommonly Difficult IQ Test Page.
A good one is the
Queendom Culture Fair IQ Test
(40 minutes, automatically scored).
These online tests are fun and you might learn a little about how smart you really are but of course they prove nothing
To really know your IQ you need to take a test validated by a professional psychologist and properly supervised.
IQ testing - Uses and Mis-uses
A major problem with IQ tests is that there is still no generally accepted theory of what intelligence actually is, so no one knows for sure what it is that IQ tests are measuring!
If there is a general form of intelligence, g, the IQ tests are supposed to measure it, but if on the other hand there is actually an independant set of multiple intelligences that we all have, then IQ could only be measuring the average of some of them. So summing up intelligence with a single number doesn't tell us our strengths and weakness in specific areas
Another big problem with IQ tests is their accuracy. All tests will have biases of some sort or another. Biases are questions that favour one group of people over another due to differences in culture or education. This is pretty serious, because, for instance it may discriminate against minority groups, such as other races. Another example of bias is of people who have had plenty of practice with IQ tests having an advantage over those who haven't
The way tests are administered and the way the results are used can also be grossly unfair. Unless instructions are understood and followed precisely, the results won't be reliable. Differences in IQ scores could be used to justify discrimination - racism for instance. Sterotyping people according to a single test number like IQ is ludicrous, but unfortunitly this is the purposes to which these tests are sometimes put.
Recently eminant biologist Stephen Jay Gould published a best selling book discussing these problems. He high lighted several part shocking abuses of IQ tests. For instance, IQ tests were used to determine positions in the US army in WWI. The tests were carried out in poor conditions such that certain minority groups were not given an opportunity to understand the instructions properly. Another example was the use of IQ tests in 1920's to discriminate against immigrants - some of the questions were ridicuously biased.
Despite all these problems with IQ tests they are more widely used today than ever. This is because they are so useful
Tests which are properly administered and designed do seem to capture some part of intelligence - the tests do seem to quite accurately predict academic and job performance. Thus they are used for selection in education and many professions. If properly used this actually helps stop discrimination because it identifies talent irrespective of race, religion etc.
At the turn of the century the top positions in French schools largely went to the upper classes, but Binets testing opened these positions to any one with talent, providing opportunities for many people that would never have had them otherwise
Another major use of IQ testing is in the study of intelligence itself and in helping people to discover their strengths and weakness
In conclusion, IQ tests have their uses, but until more is known, its best to simply regard IQ tests as a rough estimate of certain mental skills and not take them too seriously
Some people with ultra-high IQ's:
Chris Langan
has featured on the program 20/20 as 'The Smartest Man in America' His IQ is estimated at 195 and less than 1 in 100 million people would be expected to have a score this high.
He founded the
Mega Foundation
, devoted to helping the ultra-gifted. He claims to have developed a theory of everything called
CTMU
(Cognitive-Theoreotic-Model-of the Universe). Among other things this theory is supposed to prove the existance of God.
Marilyn vos Savant
is a woman who was listed in the World Guiness Book Of Records as having the highest ever recorded IQ in childhood. Her ratio IQ score of 228, corresponds to a deviation IQ score of 188.
Gregory Smith
was one of the youngest kids ever to enter College and his IQ is said to be off the scale. At 10 years of age he embarked on a college course aiming to become president of the US, design space stations and cure all the worlds major diseases.
Central debates about Intelligence
*Men are from Mars, Women are from Venus
There isn't believed to be any mean differences in IQ between the sexes, but it is thought that males display more extremes of intelligence.
In terms of specific skills, females do best at the verbal and social, where as males excel in spatial and logical ability
*A question of race
There appear to be differences in mean IQ between races, as summarized in the controversial best selling book 'The Bell Curve' The debate is focused on the cause of the difference, with critics contending that the IQ tests are biased or that differences in socio-economic status is to blame
Though there may well be real differences in IQ between races, this knowledge would appear to have no practical benefit, and because such knowledge could be used to support racist propoganda or other such political clap-trap a strong case can be made for dis-continuing this line of research
*Are we getting smarter?
Some studies in the 80's by a New Zealander, Flynn (1984, 1987) show something pretty interesting - all over the world, average raw scores on IQ tests have gone up massively! The gain is close to 14 IQ points over a 46 year period.
What is the cause? Are aliens bombarding our brains with some sort of ray? Some theories are that we really are getting smarter due to better nutrition and increased stimulation. On the other hand, perhaps we are not actually getting any smarter and people are scoring higher on the tests simply because they are becoming more familiar with the types of abstract question found in them
*Is intelligence something absolute or is it relative to each culture?
There are actually two quite different ways of looking at intelligence. The way Binet conceived of intelligence is quite different to the way that people like Terman, Spearman and Burt did so.
Binet didn't want to consider intelligence as a thing in itself, but as something more like a behaviour pattern which enables each person to adapt well to the envirnoment that they are in - or as he put it the ability to display 'good judgement'
Terman, Spearman and Burt on the other hand, wanted to consider intelligence as something innate, something which could be measured objectively irregardless of ones cultural background.
The British psychologist Robert Serpell studied life in Zambia and he found that things like the language, needs and beliefs of a society will to some extent determine what people regard as 'intellligence'. For example a Zambian who is an expert at building bush huts has a certain 'practical intelligence' in situations when that skill is neccessary.
*Is it our genes or our environment?
Extreme environmentalists such as Kamin(1947) hold that there isn't any evidence at all for genetic determination, saying that most differences in intelligence could be caused by the environment, such as diet and stimulation.
On the other hand geneticists such as Jensen (1969) and Eysenck (1979) maintain that genes play a fairly strong role in explaining IQ differences.
One way in which these theories are tested is by studying identical twins who have been seperated at birth. Recent twin studies appear to favour the genetic theory, but the degree to which differences in intelligence are caused by genes is still un certain. Figures for modern America range from 40% (Plonin, 1989) and 80% (Eysenck)
The quest to raise intelligence
It may seem that if differences in IQ have a large genetic componant then IQ cannot be much changed, but this is not the case.
To see why, consider the example of height. It is known that differences in height are 90% genetically determined, but despite this there have been substantial changes in average height in industralised nations over the past century, due to better nutrition.
Then theres the Flynn effect, which appears to demonstrate a substantial change in average IQ in only 50 years - human's couldn't possibly have changed genetically over such a short period - so the change in IQ must be due to changes in peoples envirnoment. If its confirmed, the Flynn effect offers great hope that intelligence can be substantially changed for the better.
Trouble is, of course, that no one has yet worked out a proven method through which we can all make ourselves smarter.
There are numerous programs which have been developed to try to make children smarter. For instance in the States, the Glen Doman Institute has a program which involves stimulating a childs senses. But an investigation by Spitz (1986, 1988) who surveyed many of them, could find no actual evidence that any of them worked.
Recently some research suggested that listening to classical music like Mozart could temporarily raise ones IQ, but lator studies didn't bear this out.
The most promising approach so far appears to come from special thinking strategies developed to improve specific areas. Each 'strategy' is a special technique or way of thinking about something. Techniques have been developed for things such as memory, reading andproblem solving, and they seem to vastly imrpove performance.
Champions of this approach are Tony Buzan and Edward De Bono. They've published a number of books in which they explain that the natural powers of the human mind are not being properly harnessed and outline the special techniques they've developed to remedy this.
Genius, IQ and madness
Genius and intelligence are not the same thing. Genius is beleived to be a combination of a number of different mental traits, which are:
*High IQ
*Intense concentration
*Creativity
*Rationality
*Persistance
*Specialist skills
So a person with a high IQ alone will not neccessarily be a genius, whereas a people with a very average IQ may well be. In general though, geniuses do have above average IQ's.
It has long been beleived that there is a connection between high IQ and mental illness. Some early studies seemed to suggest that the higher a persons IQ, the more suspectible they are to suffering from mental illness at some point their lives, but today the claim is still unproven. This could well turn out to simply be a popular myth.
Never the less through-out history there are examples of geniuses who did not remain completely sane. A famous example is that of the artist Vincent Van Gogh, who cut off his ear. So...should one start to feel strange urgings to shave off body parts, this could indicate signs of genius.
Some geniuses from history
Here are 10 people from history that many regard as true geniuses. The accomplishments of these people serves as an inspiration to us all!
*Charles Darwin(1809-1882)
He served as a naturalist on board several British science expeditions and developed the theory of evolution
*Albert Einstein(1879-1955)
He developed the special and general theory of relativity and won the Nobel prize in physics for quantum theory of light
*Wolfgang Mozart(1756-1791)
This Austrian musician composed some of the greatest opera, symphonies and quartets
*Sir Isaac Newton(1642-1727)
He developed the theory of gravitation and the mathematical calculus, as well as theories of optics
*William Shakespeare(1564-1616)
This Elizabethian play-wright wrote some of histories greatest plays
*Leonardo da Vinci(1452-1519)
He was a master painter, sculptor, architect, musician, engineer, inventor and scientist
*Rembrandt van Rijn(1606-1669)
Dutch baroque artist who ranks as one of the greatest painters in the history of Western art
*Galileo Galileo(1564-1642)
Mathematician, inventor and astronomer - invented the microscope and built a telescope with which he discovered the moons of Jupiter
*Benjamin Franklin(1706-1790)
US diplomat and statesman who conducted studies of electricity and invented the Franklin stove, bifocal eyeglasses and the lightening rod
*Thomas Edison(1847-1931)
Invented the light bulb and gramophone, the first storage battery and a system for distributing electric power. When he died he held 1093 patents!
Intelligence and the brain
The seat of intelligence lies somewhere in the mass of convoluted grey goo thats sitting inside our heads - this is the human brain
The major region of the brain is called the cerebrum and it consists of at least 10 billion nerve cells called neurons. Each individual neuron is on the average connected to about 10 000 other neurons by something called a dendrite
Its the region known as the cerebral cortex which appears to be associated with abstract thinking. The cerebral cortex is the outer most layer of the cerebrum and its what gives the brain its gooey appearance.
The major link with intelligence discovered so far involves the devision of the cerebrum into two hemispheres, the left and the right. It appears that verbal abilites are specificly linked to the left hand hemisphere
These fascinating discoveries were made by Roger Sperry and Robert Ornstein in the early 70's and have led to theories which attempt to devide intelligence into two different parts - logical, verbal thinking which is said to be 'left-brained' and creative, visual thinking which is said to be 'right brained'
Another major attempt to link intelligence to the brain lies in brain waves. Neurons give off electrochemical impsulses which can be detected using a machine known as an EEG (An electro encephalograph)
Recently a certain kind of brain wave has been discovered which appears to be linked to IQ. This is known as the 'evoked potential' - it occurs in response to a stimulus such as a bright light. The very bright appear to have more complex wave forms (Eysenck, 1988) and the theory is that this is because messages in the brains of bright people can travel more easily and memories are more readily layed down
Non-Human Intelligence
There have been some fascinating studies of animal intelligence. A rough attempt to estimate the intelligence levels of animals is to compare their brain weight to their body weight. As a general rule of thumb, the larger the brain to body ratio the more intelligence the animal seems to show. For example, the brain to body ratio in man is about 1:50, where as in chimpanzees the brain to body ratio is about 1:150.
The most intelligent animals aside from man appear to be the chimpanzees, followed by dolphins and dogs. Certain kinds of bird such as the parrot also show signs of high intelligence. Its been found that chimpanzees can be taught to speak a form of sign language. Marine labs in Hawaii, Flordia and the Bahamas have determined that dolphins can talk to each other using a complex systems of high pitched sounds.
Heres a recent translation of two dolphins speaking which proves their intelligence:
Dolphin One: Beep, Whistle, squeak, squeak. ('So why do you keep performing all these silly tricks for the humans - catching frisbees and jumping through hoops and so on?')
Dolphin Two: Whistle, Whistle, peep, peep ('You can get an endless supply of free fish from the humans!')
Dolphin One: Whistle, peep, beep, beep, squeak ('Great! I'm gonna get myself captured and get on the gravy train too!')
A recent study in New Zealand (2001) looked at a native parrot called the Kea. This bird has become famous for harassing tourists at ski-fields - it loves to peck at any colored object that looks interesting.
The Kea study found that the bird is so smart that in some intelligence tests it actually outperforms some apes!
Of great interest is the quest to design machines which behave intelligently, so-called artificial intelligence.
There is also the on-going search for extra-terrestrial intelligence, a search which has so far returned only negative results.
