Why Smart People Make Stupid Decisions (And How to Avoid This)


The quality of your decisions today will determine the quality of your life tomorrow.

Our decisions influence how well we make use of our talents, efforts and resources. Better decision-making improves our capability to solve bigger, more complex problems—quickly and reliably.

In this increasingly complex, disruptive and uncertain period of human history—the best decision makers will innovate, succeed and leave the rest behind.

We should also be able to rely on the smartest people to make good decisions and provide the best answers to complex problems. After all, they are ‘experts.’

But, we know this isn’t always true. Recent political events and elections across the world— especially in Europe and America—have highlighted how inaccurate expert predictions and decisions can be.

Why do smart people make stupid decisions? And, how can you avoid making bad decisions?

Let’s dive in.

Smart people and Chimpanzees

In the most comprehensive study to date on expert predictions, Professor at the University of Pennsylvania , Phillip Tetlock, gathered a large group of experts to analyse their ability to predict future events. [1]

During this study, Tetlock asked the experts to predict the probability of various events occurring i.e. Would the dotcom bubble burst? And then, he would analyse how their thought processes came to these conclusions.

After 20 years of collecting and studying 82,361 forecasts from experts, Tetlock came to a comical conclusion. According to Tetlock, the average expert…

“Is not much better at predicting the future than a dart-throwing chimpanzee.”

Tetlock suggested that most of these experts would have made better predictions if they had made random guesses.

Fortunately, there were a few experts who made good predictions.These experts had a different approach to decision-making, thinking and solving problems.

Instead of falling prey to a ‘know it all’ attitude, they made modest predictions. But, only after analysing a wide range of external data and information.

They were comfortable with uncertainty and complexity. They were open to reviewing ideas that challenged their beliefs and assumptions.

In contrast, the experts who had the most knowledge in this study were on average, the least reliable. Even after reviewing the results, they struggled to admit they were wrong.

They were overconfident and held to their beliefs, regardless of any contradictory valid evidence.

There’s a scientific explanation for this type of bias that we all struggle with. But, before we discuss this, I have a quick question and challenge for you to illustrate this point.

Confirmation Bias: “I’m Right Because I Believe I Am.”

A father and son are in a car crash and are rushed to the hospital. The father dies. The boy is taken to the operating room and the surgeon says, “I can’t operate on this boy, because he’s my son.”

Question: How is this possible?

I’ll reveal the answer to this question shortly. In the meantime, let’s get back to discussing why smart people make stupid decisions.

There are several mental errors that affect our decision-making, but by far the most powerful is “confirmation bias.”

Confirmation bias refers to our tendency to look for and favour evidence that confirms our pre-existing beliefs, whilst simultaneously ignoring or devaluing information that contradicts our beliefs.

There’s a reason for this. We experience discomfort whenever we face ideas or information in conflict with our current beliefs.

To relieve this tension and discomfort, we seek to re-confirm our existing beliefs—even if they may still be wrong.

Don’t believe this could happen to you?

Let’s get back to the question I asked you earlier. What was your answer?

If you struggled to think of any reasonable answer, don’t beat yourself up. Confirmation bias affected your ability to uncover the correct answer.

And, in case you’re wondering, the correct answer is simple—the surgeon is the boy’s mother.

In hindsight this is obvious, but it’s possible that you unconsciously overlooked the possibility of a female surgeon. Instead, you searched for solutions to the problem that were wrong, but maintained your beliefs of the surgeon being male. [2]

I’m sure you can now see how confirmation bias affects our decision-making abilities and may lead us to making stupid mistakes.

It restricts the information we choose in making our decisions. It leads to a bias in interpreting this information and distorts our memory.

This is why smart people make stupid decisions.

The more knowledge you have, the more confirmation bias you will struggle with and the more likely you’ll reject ideas that differ from your own.

Once we become close minded, we are prone to making bad decisions, even more so than a person with much less knowledge than us.

Now that we’ve discussed this, how can you best combat your confirmation biases and avoid making bad decisions?

Disprove Yourself

“Great doubts, deep wisdom. Small doubts, little wisdom.”

—Chinese proverb

Here are two simple steps to help you avoid making bad decisions…

Step 1: Practice Self-Awareness.

You can’t change what you don’t know exists. This is why being aware of your own limitations in making rational decisions is so important.

Studies have shown that self-awareness exercises that encourage you to slow down and relax could also help you to improve your creativity and decision-making. [3]

Deliberately focusing your attention on what is important is a skill that develops with practice and patience. It’s simple and powerful.

Step 2: Disprove yourself.

It takes courage to admit you’re wrong after the fact. It takes even more courage to disprove and challenge your own assumptions before the decision.

Next time you’re faced with a problem or challenge, seek out all possible ideas that may contradict your current beliefs.

This will prepare you to make a well-rounded good decision, instead of an irrational bad decision based solely on your beliefs and emotions.

Another variation of this type of thinking (first principles) has also been used to create innovative, breakthrough ideas. Across history, great thinkers including the likes of philosopher, Aristotle and Billionaire Entrepreneur, Elon Musk, credit this for contributing to their success.

Overconfidence Kills

Smart people make stupid decisions because they struggle with the same challenge that we all do—overconfidence.

Overconfidence causes us to be close minded towards different ideas than ours. It makes us slow and rigid in adapting to change.

It prevents us from solving complex problems and dealing with uncertainty with confidence.

And, worst of all, it leaves us vulnerable to making bad decisions that could cost money, time and possibly, lives.

Next time you feel absolutely certain about a decision, remember that you may be wrong.

Stay open-minded to the possibility that there is a lot more information that you don’t know yet.

After all, the wisest person in a room listens more than the others because they know there’s still more knowledge to learn.

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1. Tetlock, P.E, Expert political judgment: How good is it? How can we know?Princeton University Press. 2005.

2. This popular riddle is often cited as a demonstration of our tendency for gender bias in some research studies.

3. H.A. Slagter et al., “Mental training affects distribution of limited brain resources”(2007) PLoS Biology, 5(6): e138.