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What Are the Hazards of Having a High IQ?

Part 1: Being blessed with a high IQ doesn't mean you won't act dumb.

Key points

  • You could be very IQ-smart, yet be a poor planner, have subpar social skills, or make disastrous business decisions.
  • Although IQ tests effectively assess deliberative skills, they don't assess how much we're inclined to make use of them in real-life situations.
  • A supposedly smart person's assumptions and biases can negatively impact their ability to think objectively.
Przemyslawr Jahr, photographer/Wikipedia Commons
Source: Przemyslawr Jahr, photographer/Wikipedia Commons

Looked at contemporarily, probably the president whose native intelligence has been most frequently questioned is George W. Bush. According to Shane Frederick of Yale University, his IQ score has been estimated as above 120, which would place him in the top 10% of the population. Yet rarely is he seen as having a superior intellect. Bush himself has portrayed his thinking style as "not very analytical."

Keith Stanovich (Emeritus Professor, University of Toronto), who has published several books, including What Intelligence Tests Miss (2009) and Rationality and the Reflective Mind (2011), has done exhaustive research on the cognitive basis of rationality. Having so many times encountered people with high IQs whose words and deeds didn't suggest superior mental functioning, he concluded that the standard tests used to assess intelligence were deficient in evaluating such factors as (1) how critically an individual processed information, and (2) how well they could sidestep intuitive cognitive biases that blunt better judgment.

Standard tests are unquestionably effective in ascertaining one's native capabilities in logic, learning, abstract reasoning, and a variety of other well-established indicators of general intelligence. But they're limited in measuring abilities crucial to arriving at good decisions in actual life situations—that is, thinking rationally about matters all of us must cope with on a daily basis. For example, you could be very "IQ-smart," yet have poorly developed social skills or be prone to pernicious business investments.

IQ Testing and the Nitty-Gritty of Real Life

Looking at this paradox on a purely physical plane, David Perkins of Harvard University compares this conundrum to a person whose superior height (over 7 feet, perhaps) would seem to warrant his being considered for the uppermost echelon in basketball (i.e., the NBA). But the author emphasizes that height alone isn't nearly enough to ensure that the individual would embody sufficient athletic skills to succeed at that sport at any level.

So anyone who assumes that simply because someone is exceptionally tall they should excel at basketball just isn't thinking logically. And the same is true for assuming that because of a person's outstanding IQ "height" they must be intellectually brilliant. This is why Frederick sees it as crucial to explore the differences between rational thinking ability and formal/test appraisals of intelligence. He points out that in his experiments posing counterintuitive questions to high-IQ students, all too often he received responses that felt intuitively right to the respondent but were nonetheless incorrect. Thus he had to conclude that without careful reasoning, even those scoring high in standard intelligence tests were just as apt to get questions wrong as those with average IQs.

Noting that our brains use different systems to process information—one intuitive and spontaneous, the other deliberative and reasoned—he observed that using the former can "trip us up ... when we overvalue our own egocentric perspective." Contrariwise, using deliberative processing is core to dynamic problem-solving and can enable us to avoid the hazards of more impulsive, over-confident thinking.

What makes this so ironic is that although IQ tests do effectively assess deliberative skills, involving reasoning and the use of working memory, they don't assess how much we're actually inclined to employ them in real-life situations. Consequently, if people with high measured intelligence act on the basis of gut feelings, not taking the time or trouble to verify what they're intending to do through a painstaking rational process, they're likely to wind up doing something illogical or foolish.

Anyone can overthink things. Still, it's essential to conscientiously think things through before taking an action that could come back to haunt us. Additionally, if we develop the habit of analyzing beforehand the probable outcomes of what we say or do—particularly in the context of personal and professional relationships—we might be a lot more successful than individuals who fail to do so, even though their innate IQ may significantly exceed our own.

Native Intelligence and Decision-Making

Overall, Stanovich and several others have found only a weak correlation between inborn intelligence and successful decision-making. And that's primarily because a supposedly smart person's assumptions and biases (whether educational, social, cultural, economic, or environmental generally) can negatively impact their ability to think objectively.

Take the ludicrous circumstance of a person dropping their keys in the dark and then looking for them where there's a bright street light. If their lost keys are several yards removed from where they're searching, they could hardly be seen as smart—obviously not in any situation where their distraught emotions get the better of them, rendering their gifts for higher-order reasoning missing in action. Rather, their wrongheaded behavior would have to be construed as unthinking—or, well, "dumb." And while, admittedly, this example may seem far-fetched, it's not that far afield from what allegedly smart people can do (and at times embarrassedly admit to).

If in fact it's possible for smart people to act stupidly, it's because of their stubbornly entrenched predilections; their need to avoid what could cause them anxiety, anger, or grief; or their feeling rushed or under intense pressure. One particularly curious survey in the mid-1980s in Canada found that no fewer than 44% of the members of the high-IQ society, Mensa, believed in the pseudo-science of astrology. That might reflect well on their imaginations but hardly suggests the rationality or good judgment representing an intrinsic aspect of superior intelligence.

In the end, there may be little that's more important in avoiding careless, ego-based mistakes than possessing common sense—which, frankly, isn't all that common. And having a high (or even super-high) IQ doesn't guarantee that a person will exemplify this perhaps most enviable cognitive trait. In his aptly titled "The Surprising Downsides of Being Clever," award-winning science writer David Robson provides us with some facts that, at this point, might not surprise us at all. It's certainly suggestive that:

People who ace standard cognitive tests are in fact slightly more likely [than others] to have a 'bias blind spot'. That is, they are less able to see their own flaws, even . . . though they are quite capable of criticising the foibles of others. And they have a greater tendency to fall for the 'gambler's fallacy'—the idea that if a tossed coin turns heads 10 times, it will be more likely to fall tails on the 11th. [And also] why someone with an IQ of 140 is about twice as likely to max out their credit card.

This is the first part of a two-part post. Here's the link to the second part, "13 Reasons Why Having a High IQ Can Make You Less Happy,"

© 2021 Leon F. Seltzer, Ph.D. All Rights Reserved.


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