IQ: What is it? How does one Get it?
Paul V. Hartman
Those involved in the study and research of IQ and how it is acquired have a method to segregate a human population into 5 groups: Very Dull (in many textbooks, the name is "retarded"), Dull, Normal (also called Average), Bright, and Very Bright. This division is based on what they call the "standard IQ test", which uses scores covering a range from a low of 50 to a high of 150.
As most people know, "IQ" when plotted in this 5 group distribution assumes a "bell shaped curve", as does most things when a large population is arranged in groups using any discriminator, such as skin pigmentation, hair color, or maximum height. Using hair color as the example, there will be a "median" in which the majority of the study will fall, which is brown, and as one moves away from the median, to the left might be "blond" and to the right might be "black".
Whoops. I was trying to be indifferent about direction, in my example. More accurately, I should have written "to the right might be "blond" and to the left might be "black". I can hear the leftist screams already.
IQ, or cognitive ability in humans, follows such a curve. The middle of the curve, and the apex of the bell, is given the number 100. That number is also the Median. The Average population, or Normal group, falls 10 points on either side of the median, so the range of "normal" is 90 to 110 in IQ scores.
Because it gets increasingly difficult to test dull people below an IQ of about 75, values below 50 become problematic: it is the area of the curve where the Y value is very close to the X horizontal line; the area of the curve known as "asymptotic."
The same thing happens at the upper end because the test is made up by people in the "Bright" group but with little contribution from those in the "Very Bright" group, who can't be bothered making up tests. (They tend to be a bit quirky. Not all but enough to take notice.) Nevertheless there is a woman named Marilyn vos Savant who writes a magazine column on puzzles and tests of knowledge, and who describes herself as having the "highest IQ score recorded", at 180 (*). Note that "savant" means "learned scholar" from the root word meaning "wise". How fortunate to be born to a parent whose last name would identify the IQ of a daughter! We can agree that if she is over 130 she is in the cognitive elite, but if there is a substantial difference between 130 and higher numbers no one can prove it. The statistical problem is "small sample size" and a thing known as "ceiling bumping".
Those with "average" cognitive ability, a score of 90 to a score of 110, make up half the human population. Above 110 to a score of 125 is the Bright group, and within this group will be found most physicians, science professors, dentists, lawyers, architects, engineers, and corporate executives. College professors in Education, Sociology, Literature, History, and similar non-scientific subjects come primarily from the Average group. (Indeed, college professors in "Education" may come primarily from the low end of "normal".)
The Very Bright group constitutes 5% of the population. (As does those in Very Dull.) Most of this group scores between 125 to 135 on the standard IQ test. MENSA, the British association for intelligent people, requires members to be in the 98th percentile (which equates to an IQ score of 132) meaning the top 2% of those with IQ scores. Those above 140 are in an even smaller group. You may have such a person as a friend and not know it.
The standard IQ test (for decades it has been the Stanford-Binet Intelligence Scale), is not a measure of knowledge, but a measure of ability. To illustrate this, consider a question which displays a pile of equal sized blocks stacked in a random arrangement, in which you view the pile from a particular direction. That direction is such that you cannot see how many blocks are behind the tallest ones: there may be several, or none. Your question is to view a series of 5 pictures supposedly showing what the stack of blocks looks like from another direction. You must select the only one that could qualify, knowing that the other four cannot represent that stack of blocks on the basis of what you know about the view that you DO see. The average person ponders the 5 views and ends up guessing. The Very Bright gets it straight off.
Repeat that type of query a dozen times and you will eliminate the Average from scoring high on guess alone, while the Very Bright will get them all correct.
An IQ test does not ask you to name the first 30 US presidents, in chronological order. That is a test of knowledge. A person with a high IQ has the capacity to learn a lot of things, the opportunity to do so, and probably the desire to do so. But this extra knowledge is not measured by the IQ test. The ABILITY to know, is what is measured, and the questions are designed to reveal that, and that only.
Another IQ test item can be a series of objects in which one of them does not quite fit the group as well as the others. Consider these objects: a square, an isosceles triangle, a circle, a quarter moon, and a pentagon, all of equivalent size. The odd one out is the crescent. All the others have even sides, though the number of sides varies. One can see how the IQ test, therefore, can be independent of such factors as education, cultural environment, parent income or where they live, immigrant status, or language.
IQ tends to be steady after the age of 10 in any particular person, over their life span. Thus one may test 8th graders and have a good idea of what their future will be like. IQ appears to be at least 80 % due to DNA, and only 20% due to education, social environment, and other factors. Thus, IQ is far and away genetically determined, and can be influenced only minimally by exterior factors like education and the culture lived in.
The cognitive elite gets rich when others struggle to stay even. They are increasingly segregated physically from everyone else in both the workplace (by their choice of work) and the neighborhood (by choosing to live where like-minded people live). Males and females in this group are increasingly likely to intermarry. They are, then, self-segregating. However, they are not necessarily happier than average IQ people. I threw this in as I know some people wonder about that.
Information in this essay was obtained from the 1994 book "The Bell Curve", by Richard Herrnstein and Charles Murray. It is worth reading if only for what it predicts in later chapters about "the coming custodial state" ever since Obama captured the White House and "changed" America.
(*) Since the IQ score range ends with 150, or more accurately, becomes asymptotic at that location, you can get IQ scores above 150 only by testing at a younger age, and then multiplying by a fudge factor to relate the score to an older group. Using this method, scores as high as 250 have been claimed. Such claims are absurd. If there are reliable ways to evaluate IQ above 150, or even 130, the method has yet to be proven. The sample size is extremely small. And anyway, what does it mean? Is the world's "richest man" made less well off when someone appears who is "more richer"?