What is the essence of intelligence? Answers vary, but it comes down to how well you adapt to your environment—to the degree of skill and ingenuity you bring to that challenge. And in a world dominated by abstract concepts, complex systems, and symbolic information overload—a circumstance that wasn’t true for our Neanderthal ancestors—it’s no surprise that this ability is closely linked with reasoning speed, learning potential, and knowledge. In other words, intelligence is the capacity to problem solve by finding patterns and connecting ideas faster and better than others. The question is, What’s the best way to measure it?
Although most people hate IQ tests, few psychological findings are as conclusive as the correlation between IQ test scores on one hand and academic performance, job performance, and career success on the other.
Scoring highly on an IQ test can forecast significantly higher success levels in all areas of life. In fact, even though IQ tests were initially designed to predict only school achievement, more than a century’s worth of scientific research has shown they’re also predictive of other, seemingly nonintellectual achievements, like better, longer, and happier romantic relationships, creative and artistic talents, socioeconomic status, and even health and longevity. IQ tests have even been found to predict a person’s life expectancy as well as personality traits like self-control, prudence, and risk taking.
So while environmental and other factors play a role in all these things–and correlation doesn’t mean causality–there’s still arguably no single better way to measure someone’s adaptability potential (especially relative to others in similar circumstances) than through an IQ test.
That’s not to say that IQ tests are the only way to measure intelligence. In fact, we make informal inferences about others’ intelligence all the time, even after short interactions. It only takes a few minutes after meeting someone for most of us to judge how smart, competent, or quick-witted we think they are. After that point, we’re generally reluctant to change our initial views even after seeing solid contrary evidence. Psychologists have found there really is no second chance for a first good impression.
What’s more, our informal beliefs about others’ intelligence don’t need to be accurate to be consequential. We may think someone is smart when in fact they aren’t, but we will nonetheless treat that person as though they are–interpreting their behaviors as indicative of intelligence, just to confirm our initial prejudices.
But our intuitive judgments aren’t always wrong. Studies show that our informal evaluations of other people’s intelligence aren’t totally disconnected from their actual IQ scores. For example, our friends, romantic partners, and closest work colleagues all tend to have similar IQs to our own, even though we never explicitly selected them on that basis or tested their IQ scores. Likewise, when we’re asked to estimate the intelligence of acquaintances, classmates, or coworkers, those guesses do correlate to their actual IQ scores. On the other hand, people tend to be less accurate at estimating their own IQ scores; most of us think we’re more intelligent than we actually are.
Believing someone to be smart isn’t just a matter of guessing their IQ score. We usually take a wide range of signals into account as well. For instance, emotional intelligence can predict one’s ability to navigate stressful situations, and openness to experience can predict the ability to learn to think critically. Judgment and ambition also play important roles–determining, respectively, how well somebody might perform at a certain task, and how adamantly they’ll pursue their goals, independent of their actual IQ score.
All this explains why high IQ scorers don’t always have a reputation for being smart, and–conversely–why some of the most successful people may not have exceptionally high IQs.
IQ tests may get a bad rap, but they still set a useful benchmark for judging intelligence. At any rate, our curiosity to understand how smart people are wouldn’t vanish if we abolished IQ tests. Still, it’s wrong to assume that people’s success is purely a reflection of their intelligence (an idea that’s served as the basis for Social Darwinism and other false, and dangerous, theories). Contextual factors always matter. Other personality factors matter, too. And there’s no shortage of examples of smart people who make stupid decisions that cost them dearly. In the end, real life is the ultimate IQ test.