Idiot Brain - What Your Head Is Really Up To

But don’t go thinking it’s all pointless speculation; there are many aspects of intelligence that are generally agreed on: it reflects the brain’s ability to do . . . stuff. More precisely, the brain’s ability to handle and exploit information. Terms such as reasoning, abstract thought, deducing patterns, comprehension; things like this are regularly cited as examples of superior intelligence. This makes a certain logical sense. All of these typically involve assessing and manipulating information on an entirely intangible basis. Simply put, humans are intelligent enough to work things out without having to interact with them directly.

For example, if a typical human approaches a gate held shut with large padlocks, they’ll quickly think, “Well, that’s locked,” and go find another entrance. This may seem trivial, but it’s a clear sign of intelligence; the person observes a situation, deduces what it means, and responds accordingly. There is no physical attempt to open the gate, at which point they’d discover, “Yep, that’s locked”; they don’t have to. Logic, reasoning, comprehension, planning; these have all been utilized to dictate actions. This is intelligence. But that doesn’t clarify how we study and measure intelligence. Manipulating information in complex ways inside the brain is all well and good, but it’s not something that can be observed directly (even the most advanced brain scanners just show us blurs of differing color at present, which isn’t especially useful) so measuring it can be done only indirectly by observing behavior and performance on specially designed tests.

At this point, you might think that something major has been missed here, because we do have a way of measuring intelligence: IQ tests. Everyone knows about IQ, meaning Intelligence Quotient; it’s a measurement of how smart you are. Your mass is provided by measuring your weight; your height is determined by measuring how tall you are; your intoxication level is calculated by breathing into one of those gadgets the police make you breathe into; and your intelligence is measured by IQ tests. Simple, right?

Not exactly. IQ is a measurement that takes the slippery, unspecified nature of intelligence into account, but most people assume it’s far more definitive than it is. Here’s the important fact you need to remember: the average IQ of a population is 100. Without exception. If someone says, “The average IQ of [country x] is only 85,” then this is wrong. It’s basically the same as saying, “ The length of a meter in [country x] is only 85 cm”; this is logically impossible, and the same is true for IQ.

Legitimate IQ tests tell you where you fall within the typical distribution of intellect in your population, according to a proposed “normal” distribution. This normal distribution dictates that the “mean” IQ is 100. An IQ between 90 and 110 is classed as average, between 110 and 119 is “high average,” between 120 and 129 is “superior,” and anything over 130 is “very superior.” Conversely, an IQ between 80 and 89 is “low average,” 70 to 79 is “borderline,” and anything below 69 is considered “extremely low.”

Using this system, over 80 percent of the population will fall in the average zones, with IQs ranging from 80 to 110. The further out you go, the fewer people you’ll find with these IQs; less than 5 percent of the population will have a very superior or extremely low IQ. A typical IQ test doesn’t directly measure your raw intelligence, but reveals how intelligent you are compared to the rest of the population.

This can have some confusing consequences. Say a potent but bizarrely specific virus wiped out everyone in the world with an IQ of over 100. The people left behind would still have an average IQ of 100. Those with IQs of 99 before the plague hit would now suddenly have IQs of 130+ and be classed as the crème de la crème of the intellectual elite. Think of it in terms of currency. In the US the value of the dollar fluctuates in accordance with what happens in the economy, but there are always 100 pennies to the dollar, so the dollar has values that are both flexible and fixed. IQ is basically the same: the average IQ is always 100, but what an IQ of 100 is actually worth in terms of intelligence is variable.

This normalization and adhering to population averages means that IQ measurement can be a bit restrictive. People such as Albert Einstein and Stephen Hawking reportedly have IQs in the region of 160, which is still very superior but doesn’t sound so impressive when you consider the population average is 100. So if you meet someone who does claim to have an IQ of 270 or some such, they’re probably wrong. They’ve been using some alternative type of test that isn’t considered scientifically valid, or they’ve seriously misread their results, which does undermine their claim to be a super genius.

This isn’t to say that such IQs don’t exist at all; some of the most intelligent people on record supposedly had IQs of over 250, according to the Guinness Book of Records, although the category of Highest IQ was retired in 1990 due to the uncertainty and ambiguity of the tests at this level.

The IQ tests used by scientists and researchers are meticulously designed; they’re used as actual tools, like microscopes and mass spectrometers. They cost a lot of money (so aren’t given away online for free). The tests are designed to assess normal, average intelligences in the widest possible range of people. As a result, the further to the extremes you go, the less useful they tend to be. You can demonstrate many concepts of physics in the school classroom with everyday items (for instance, using weights of different sizes to show the constant force of gravity, or a spring to show elasticity) but, if you delve into complex physics, you need particle accelerators or nuclear reactors and frighteningly complex mathematics.

So it is when you have someone of extremely high intelligence; it just becomes much harder to measure. These scientific IQ tests measure things such as spatial awareness with pattern completion tests, comprehension speeds with dedicated questions, verbal fluency by getting the subject to list words from certain categories, and stuff like that; all reasonable things to look into but not something that is likely to tax a super genius to the extent where it would be possible to spot the very limits of his or her intelligence. It’s a bit like using bathroom scales to weigh elephants; they can be useful for a standard range of weights, but at this level they’ll give no useful data, just a load of broken plastic and springs.

Another concern is that intelligence tests claim to measure intelligence, and we know what intelligence is because intelligence tests tell us. You can see why some of the more cynical scientist types wouldn’t be happy with this situation. In truth, the more common tests have been revised repeatedly and assessed for reliability often, but some still feel that this is just ignoring the underlying problem.

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