Skip to main content

Verified by Psychology Today

3 Reasons Why Smart People Do Dumb Things All the Time

An investigation into the science of smart decision making.

Rawpixel com/Shutterstock
Source: Rawpixel com/Shutterstock

Every day, at least one smart person doesn’t wear a seatbelt, crosses the street without looking both ways, or hits reply-all when she really meant to reply to one person. The repercussions of these offenses, which range from mild embarrassment to untimely death, are familiar to all of us. We heed ample warnings from parents, teachers, friends, and colleagues—and if that doesn’t sufficiently caution us, we simply refer to those real-life what-went-terribly-wrong stories that someone you know always seems to know: So and so died because he didn’t wear a seatbelt, or got hit by a car because she crossed the street when she shouldn’t have.

When we hear these stories secondhand, it’s easy to dismiss the victims as stupid or careless. We might wonder, “Why weren’t they thinking?" At the same time, we don’t think twice about getting into a taxi and not wearing a seat belt or running across the street when cars are speeding toward us. (I am guilty of bot.) Somehow we are able to ignore our innate common sense and engage in this risky and foolish behavior. Why?

One answer, according to Heather Butler, an assistant professor of psychology at California State University, is that smart people aren’t actually all that smart. In a recent article for Scientific American, Butler tackles the subject of why smart people behave foolishly by differentiating between intelligence and critical-thinking skills. She argues that intelligence, which is largely measured by IQ and test scores, is largely unrelated to critical thinking, “a collection of cognitive skills that allow us to think rationally in a goal-oriented fashion, and a disposition to use those skills when appropriate.” In simpler terms, skilled critical thinkers rely on logic, facts, and evidence to help guide their opinions and behavior.

For a real-world example, look at the difference between climate change believers and deniers. Most of the scientific community (97 percent) strongly believes that climate change is a real threat to the environment, citing measurable data points, including increased CO2 in the atmosphere, droughts, temperatures, and sea surface temperatures. Meanwhile, as Motherboard puts it, climate change deniers, which make up as much as half of the U.S. Congress, chalk it up to “solar activity, corruption among scientists, Al Gore, and the discerning will of God.” They also claim that the Earth’s climate has always been changing, which is technically true, until you are presented with recent studies which suggest that the planet should now be entering a cooling, not warming period. This is not to say all climate change deniers are inherently stupid. Some skeptics are, in fact, objectively intelligent people, according to a study published in Nature Climate Change. Researchers found that their belief (or disbelief) stems from a conflict of interest “between the personal interest individuals have in forming beliefs in line with those held by others with whom they share close ties and the collective one they all share, in making use of the best available science to promote common welfare.” That is to say, these otherwise intelligent individuals simply choose party over country—or, in this case, facts.

A lack of critical thinking skills may not be the only reason why otherwise smart people engage in dumb behavior. The “What the Hell” effect has been closely associated with the psychology of dieting. Dieters who struggle with self-control know the scenario all too well: You promise to deny yourself sweets, but eventually you cave and take one bite. And since you already took that one bite, you think to yourself, “What the hell? I already ruined this diet,” and finish off the entire bag. This effect doesn’t only apply to eating or drinking: Many of us are quick to sacrifice our willpower (and best intentions) when it comes to goals related to personal relationships, shopping, or even work. You already texted your ex once? Might as well text him again. You already went over your budget? A couple hundred more dollars won’t make much of a difference. Yet, when they happen to us, we tend to interpret these actions as moments of weakness, not stupidity.

This brings us to the third reason why intelligent people make foolish mistakes: Smart people tend to think they are smarter and better than everyone else. In the cookie-binging example, a smart person might blame the person who baked the cookies instead of the person who ate them. Professor Andre Spicer refers to this as the self-serving bias:

Not everyone can be above average—but we can all have the illusion that we are ... We collect all the information we can find to prove ourselves right and ignore any information that proves us wrong. We feel good, but we overlook crucial facts. As a result, the smartest people ignore the intelligence of others so they make themselves feel smarter.

This explanation might best explain why so many of us think seat belts are optional, or that running into traffic is fine, or driving like a maniac is perfectly acceptable. We elevate our abilities, our luck, and our smarts so much that we believe we are invincible, and if something does happen to go awry, it’s not our fault. While self-serving bias helps to protect and boost our self-esteem, the obvious downside is that it might weaken our sense of personal responsibility and our ability to realize when we are, in fact, being stupid.