For many people, intuition is pineapple on their decision-making pizza. You either love or hate it. And your choice puts you in one of two schools of thought led by star psychologists.

Intuition-skeptics often swear by Nobel Prize winner Daniel Kahneman. He’s a psychologist and economist who called out a long list of mental biases that display how bad we, humans, can be with logic.

On the opposite front, the name Gary Klein often comes to mind. The psychologist and prestigious consultant coined naturalistic decision-making, which celebrates intuition and combines it with analysis.

In 2009, Kahneman and Klein confronted their work about intuition. Like many, I’d expected the result to be a bloody war of intellect. What came out instead was an elegant article titled “Conditions for intuitive expertise: A failure to disagree.”

We’ll go through the main questions Kahneman and Klein answered in their paper and a joint interview.

When can you trust your gut?

“It depends on what you mean by trust,” Klein said. “If you mean, My gut feeling is telling me this; therefore I can act on it and I don’t have to worry, we say you should never trust your gut.”

Klein suggests you consider intuition as a piece of the puzzle, not the entire picture. Good decision-making requires you to add other elements to the equation — like context, previous experience, and external opinions.

“You need to take your gut feeling as an important data point, but then you have to consciously and deliberately evaluate it, to see if it makes sense in this context,” Klein added. “You need strategies that help rule things out.”

The catch? Not everyone has precise decision-making strategies ready to be executed nor enough time to carry out a detailed analysis. That’s why Kahneman sees intuition as a necessary compromise.

“When you are under time pressure for a decision, you need to follow intuition,” Kahneman said. “My general view, though, would be that you should not take your intuitions at face value.”

Kahneman and Klein answered the same question differently but their insights complete each other. You can only trust your intuition if you keep in mind two things.

1. Intuition isn’t enough: It should be a part of the decision-making process, not all of it.
2. Intuition is often a necessity: It’s a shortcut we take when we lack time and resources.

This overview doesn’t take into account the quality of your intuitive judgment. The said quality varies according to the context and your past experience which is what we’ll see in the following section.

Under which conditions can you develop a reliable intuition?

The short answer is high validity environments.

High validity environments involve situations you can predict. For instance, eye surgeons work in a high validity environment because all patients share the same eye structure and encounter similar problems. Upon treating hundreds of cases, eye doctors can develop reliable gut feelings that help them diagnose illnesses faster and react better to potential problems during surgeries.

In contrast, low validity environments come with great amounts of uncertainty. For example, picking single stocks is a zero-validity environment because the market is unpredictable. No stockbroker can develop single-picking expertise. At best, It’d be a whim based on one’s personal taste and reflexes, not skill. That’s why solutions like index funds exist: they make up for biases and risks by diversifying investment portfolios.

Kahneman and Klein agree on the high validity v.s low validity thing but disagree on the gray area in between.

Kahneman thinks intuition doesn’t work well in not-high-enough validity environments like project management. Klein, on the other hand, says that as long as you have feedback on your decisions, your intuition can become reliable.

“Most corporate decisions aren’t going to meet the test of high validity. But they’re going to be way above the low-validity situations that we worry about,” Klein explained. “Many business intuitions and expertise are going to be valuable; they are telling you something useful, and you want to take advantage of them.”

Klein’s words sound promising until you put them next to Kahneman’s. The latter emphasizes the dangers of uncertainty even when experts are involved.

“I would be wary of experts’ intuition, except when they deal with something that they have dealt with a lot in the past. But when problems are unique, or fairly unique, then I would be less trusting of intuition than Gary is,” Kahneman said. “One of the problems with expertise is that people have it in some domains and not in others. So experts don’t know exactly where the boundaries of their expertise are.”

What makes it hard to pick a side here is the absence of a clear measurement of what’s a high-enough validity. It’s often a case-by-case approach in environments like running a business, sales, and even picking a destination for summer vacation.

When you face a decision, observe your environment and ask yourself: “Do the problems I encounter require the same solutions? Do the same actions produce the same results? Can I predict the outcomes using a formula?”

The more yeses you get, the higher the validity of your environment. From there, you can determine whether or not your intuition’s quality can appreciate over time.

Since the back and forth between Kahneman and Klein can be tricky to follow, here’s a recap of what we just saw.

• Your intuition develops like a muscle in high validity environments — like repairing the same car malfunctions or conducting eye surgeries.
• Your intuition is worthless in low validity environments— like picking single stocks or the lottery.
• In-between environments are an area of disagreement. Klein’s school of thought claims your intuition improves if you get constant feedback on your actions — like managing projects in a company or developing software.

Now that we’ve covered the theory, let’s get practical.

How do you integrate intuition into your decision-making?

Say you want to rent a new place and had visited two so far. As soon as you stepped in the first, your gut went berserk, commanding you to run away. The second pleased your intuition so much that you wanted to immediately sign the lease.

Before you make your decision, the idea is to ask yourself two questions.

1. Is rental a high validity environment for me?
2. How can I structure my decision?

Unless you’re a real estate agent, the answer to the first question is “no,” which means you shouldn’t give your intuition much weight in a rental decision. This brings us to the second question.

We’ll use two methods to analyze both options with as much rationality as possible. The first method comes from Kahneman and I use it when my intuition pushes me away from a decision. The second trick was invented by Klein, and it’s effective when intuition pushes you toward a decision.

1. Checklists

Keeping the rental example, a simplified checklist can look like this.

• Is the house well equipped?
• Is the neighborhood calm and safe?
• Is it well-situated?
• Did my contact in real estate recommend it?
• Am I excited about moving in?

“The checklist doesn’t guarantee that you won’t make errors when the situation is uncertain,” Kahneman indicated. “But it may prevent you from being overconfident.” He also added that “overconfidence is a powerful source of illusions,” and of course, you don’t want your decisions to be based on an illusion.

2. Premortem analysis

Gary Klein came up with this debiasing technique to regulate his clients’ overeagerness to an upcoming decision. Here’s how he described it.

“A premortem is the hypothetical opposite of a postmortem. A postmortem in a medical setting allows health professionals and the family to learn what caused a patient’s death,” Klein wrote for Harvard Business Review. “A premortem in a business setting comes at the beginning of a project rather than the end, so that the project can be improved rather than autopsied.”

Though Klein designed premortem for businesses, you can apply it to other contexts. With a rental, you can imagine potential issues that can ruin your stay in the house you feel compelled about.

Here’s an example.

• The house will cost a fortune to maintain because of the poor construction standards on which it was built.
• Rave parties will occupy the free space behind your yard.
• Pollution and noise will catch up to your neighborhood once the nearby construction projects come to an end.

From there, you can either look for countermeasures or reexamine your decision. Perhaps you should ask a professional for maintenance costs and ask around about the surroundings. Depending on the results of your analysis you can lock your choice or drop it.

Closing thought

Intuition is a shortcut that doesn’t always lead you where you want to go. That’s why you want to keep your rationality turned on like a GPS that shows you a bigger chunk of the map.

Lean into your gut feeling in predictable contexts and question it in environments full of randomness. Either way, try to complete your decision with analysis and keep your expectations low.