We all probably know someone who is intelligent, but does surprisingly stupid things. My family delights in pointing out times when I (a professor) make really dumb mistakes. What does it mean to be smart or intelligent? Our everyday use of the term is meant to describe someone who is knowledgeable and makes wise decisions, but this definition is at odds with how intelligence is traditionally measured. The most widely known measure of intelligence is the intelligence quotient, more commonly known as the IQ test, which includes visuospatial puzzles, math problems, pattern recognition, vocabulary questions, and visual searches. 

The advantages of being intelligent are undeniable. Intelligent people are more likely to get better grades and go farther in school. They are more likely to be successful at work. And they are less likely to get into trouble (e.g., commit crimes) as adolescents. Given all the advantages of intelligence, though, you may be surprised to learn that it does not predict other life outcomes, such as well-being. You might imagine that doing well in school or at work might lead to greater life satisfaction, but several large-scale studies have failed to find evidence that IQ impacts life satisfaction or longevity. University of Waterloo psychologist Igor Grossmann and his colleagues argue that most intelligence tests fail to capture real-world decision-making and our ability to interact well with others. This is, in other words, perhaps why “smart” people, do “dumb” things.

The ability to think critically, on the other hand, has been associated with wellness and longevity. Though often confused with intelligence, critical thinking is not intelligence. Critical thinking is a collection of cognitive skills that allow us to think rationally in a goal-orientated fashion, and a disposition to use those skills when appropriate. Critical thinkers are amiable skeptics. They are flexible thinkers who require evidence to support their beliefs and recognize fallacious attempts to persuade them. Critical thinking means overcoming all sorts of cognitive biases (e.g., hindsight bias, confirmation bias).

Critical thinking predicts a wide range of life events. In a series of studies, conducted in the U.S. and abroad, my colleagues and I have found that critical thinkers experience fewer bad things in life. We asked people to complete an inventory of life events and take a critical thinking assessment (the Halpern Critical Thinking Assessment). The critical thinking assessment measures five components of critical thinking skills including verbal reasoning, argument analysis, hypothesis testing, probability and uncertainty, decision-making, and problem-solving. The inventory of negative life events captures different domains of life such as academic (e.g., I forgot about an exam), health (e.g., I contracted a sexually transmitted infection because I did not wear a condom), legal (e.g., I was arrested for driving under the influence), interpersonal (e.g., I cheated on my romantic partner who I had been with for over a year), financial (e.g., I have over $5,000 of credit card debt), etc. Repeatedly, we found that critical thinkers experience fewer negative life events. This is an important finding because there is plenty of evidence that critical thinking can be taught and improved.

Is it better to be a critical thinker or to be intelligent? My latest research pitted critical thinking and intelligence against each other to see which was associated with fewer negative life events. People who were strong on either intelligence or critical thinking experienced fewer negative events, but critical thinkers did better.

Intelligence and improving intelligence are hot topics that receive a lot of attention. It is time for critical thinking to receive a little more of that attention. Keith Stanovich wrote an entire book about What Intelligence Tests Miss. Reasoning and rationality more closely resemble what we mean when we say a person is smart than spatial skills and math ability. Furthermore, improving intelligence is difficult. Intelligence is largely determined by genetics. Critical thinking, though, can improve with training and the benefits have been shown to persist over time. Anyone can improve their critical thinking skills: Doing so, we can say with certainty, is a smart thing to do.