When to Trust Your Gut (and When to Ignore It)

Mike Lamb
Jul 16
8 min read

We’re often told to trust our instincts – but is intuition really the best guide for making big decisions?

It’s the snap judgment in an emergency that saves a life, or the lightning-fast thinking of an elite athlete making a pass no one else saw coming. In the right context, intuition can be a powerful asset. But it can also lead us astray – making us prone to bias, blind spots and oversimplification.

So, when should you trust your gut, and when should you slow down and think things through?

Before we dive in, here’s the short iluli explainer:

What is intuition?

Albert Einstein said it was the source of his genius. It has sparked some of the most significant and influential innovations in history. We all use it to make decisions. Yet science and psychology still haven’t reached a conclusive consensus on what intuition actually is.

Joel Pearson, a psychologist and neuroscientist, describes it as “knowing what without knowing why.”

So, where do hunches and gut feelings – that sense that something just feels right – come from? Nobel-prizewinning psychologist Daniel Kahneman proposes that we have two modes of thought:

System 1 specialises in rough-and-ready thinking: fast, intuitive, and emotional. It’s the unconscious mind conjuring up answers without pausing to do the working out.
System 2 handles slow-and-steady thinking: deliberate, analytical and rational. It’s the mind consciously processing the available information and methodically solving a problem by working through the data.

System 1 can feel mysterious – even magical. So much so that you might be tempted to dismiss advice like “trust your gut” and “follow your heart” as superstitious pseudoscience. But, time and again, fast and intuitive System 1 thinking shows up like a “sixth sense” – a superpower that kicks in when we need it most. You might be someone who spends hours comparing Amazon reviews before buying a new toaster (System 2), but you probably still deferred to System 1 for the really important decisions – like getting married, choosing a home or whether to accept that big job offer.

The power of a “funny feeling”

On the night of 26th September 1983, the world came dangerously close to nuclear armageddon. Just after midnight, alarms rang out inside a secret Soviet bunker. Known as Serpukhov-15, the facility was the Soviet Union’s command centre for monitoring the early warning satellites it had positioned over the United States.

The piercing siren and flashing red screens meant that an attack was underway. Within seconds, the electronic maps on the facility’s control panels were showing that the U.S. had launched five nuclear missiles from a base in Dakota.

Stanislav Petrov was the duty officer sitting in the commander's chair that night. He had a monumental decision to make. Should he call up his superiors, who would almost certainly initiate a retaliatory nuclear attack on the U.S.? Or should he break protocol and do nothing?

With stakes that couldn’t have been any higher and limited time for a complete analysis of the incoming data, Petrov had to employ System 1 thinking, and decided it must be a false alarm. 23 minutes later – when no missiles appeared – he knew he’d made the right call.

Reflecting on how he came to the fateful decision, he later recalled: “I had a funny feeling in my gut.”

Stanislav Petrov’s intuition may have literally saved the world.

Like the lifesaving hunches of firefighters who evacuate buildings moments before they collapse (there’s more about the chief firefighter mentioned in the video here), intuition can drive some of the most consequential decisions we’ll ever make.

But there’s more to this than anecdotes and lucky guesswork. A growing body of scientific research shows that snap judgments outperform slower, more deliberate reasoning – at least when the conditions are right.

A neurological perspective

In his book Incognito: The Secret Lives of the Brain, neuroscientist David Eagleman offers a fascinating explanation of how and why these “funny feelings” work.

A cartoon image a brain surrounded by magnifying glasses, a clipboard and graphs.

In a famous experiment conducted by American scientist Antoine Bechara, volunteers were asked to select cards at random from any of the four decks of cards laid out in front of them. Each card would either reveal a financial gain or a loss. What the subjects weren’t told was that the decks had been fixed. Two were “good” and the other two were “bad”. Choose cards from the latter, and they would end up with a loss.

It took about 25 draws before the subjects were able to say which were the good decks.

But here’s where things get really fascinating:

The investigators also measured the subject’s skin conductance response, which reflects the activity of the autonomic (fight-or-flight) nervous system. And here they noticed something amazing: the autonomic nervous system picked up on the statistics of the deck well before a subject’s consciousness did. That is, when subjects reached for the bad decks, there was an anticipatory spike of activity – essentially, a warning sign. This spike was detectable by about the thirteenth card draw. So some part of the subjects’ brains was picking up on the expected return from the decks well before the subjects’ conscious minds could access that information. And the information was being delivered in the form of a ‘hunch’: subjects began to choose the good decks even before they could consciously say why.

The exercise was repeated with patients who had damage to the ventromedial prefrontal cortex – the part of the brain crucial for decision-making. Researchers found that these patients didn’t experience the intuitive “warning signal.” Even after their conscious minds had figured out which decks were favourable, they continued to choose cards from the bad ones.

“In other words,” says Eagleman, “the gut feeling was essential for advantageous decision making.”

When to slow down and think

So, science says that snap decisions are best? Well, not quite…

Cartoon signs in a variety of shapes saying "halo effect", "anchoring", "availabily heuristic", "hingsight bias", "framing" and "planning fallacy".

If you’ve watched the explainer video, you’ll be familiar with the bat and ball puzzle¹ made famous in Daniel Kahneman’s seminal Thinking, Fast and Slow. Did you get the correct answer? Here’s another one that featured in the same test:

If it takes 5 machines 5 minutes to make 5 widgets, how long would it take 100 machines to make 100 widgets?

Was the first answer that popped into your head 100 minutes? It’s the knee-jerk error most of us make before our analytical thinking kicks in.²

Intuitive thinking works by taking shortcuts. System 1 takes complexity and messiness and distils it into something much simpler. This can be hugely advantageous when we need to make an urgent, high-stakes decision where detailed analysis is not an option.

But as Daniel Kahneman showed, this simplification makes us prone to a whole range of biases and blind spots. In the case of the maths question above, our intuition generates a rapid answer by replacing the mildly difficult question with a much simpler one, and answers that one instead.

In the real world, this has significant consequences. Particularly when we’re often not consciously aware of which system we’re using.

Research has found that the way people answer the bat and ball question can predict their susceptibility to fake news. It’s not about intelligence, but thinking styles. People who rely on fast, intuitive thinking (System 1) are more likely to believe in conspiracy theories than those who engage in slower, more analytical reasoning (System 2). It’s why even highly intelligent, successful people can end up insisting the moon landings were faked.

In his book Superforecasting (the subject of an upcoming iluli video), the American psychologist Philip Tetlock sets out the attributes common to people who have an incredible ability to accurately predict the future. One of the key insights? They’re not System 1 thinkers.

As Tetlock writes:

A defining feature of intuitive judgment is its insensitivity to the quality of the evidence on which the judgment is based. It has to be that way. System 1 can only do its job of delivering strong conclusions at lightning speed if it never pauses to wonder whether the evidence at hand is flawed or inadequate, or if there is better evidence elsewhere.

The people who make the best judgements about the future are methodical, analytical and constantly on the lookout for new evidence to disprove and improve their forecasts.

When to trust your gut

Our unconscious brain is constantly processing far more than we realise. This makes intuition a powerful tool – used in the right context. But under what circumstances should we trust our gut?

Speech bubbles with the phrases "first impressions never lie", "trust your instincts", "look within", "heed your inner voice" and "do what feels right"

This was the subject of intense debate between two of the leading thinkers in this field – Daniel Kahneman and Gary Klein. Kahneman, as you’ll have gathered by now, was an intuition-sceptic. He recommended consulting intuition only after careful analysis of objective facts. Klein, however, saw intuition as a skill that could be honed. For him, good decision-making began with intuition, which could then be refined through analytical thinking.

The pair engaged in an “adversarial collaboration” to see if they could reach a consensus. And they did… sort of. Kahneman conceded that: “There are some conditions where you have to trust your intuition.” Even though he was strongly of the view that intuition should be suppressed as long as possible in most circumstances.

Kahneman and Klein identified two key factors which determine when intuition is reliable: structure and feedback. They explained in a joint interview with McKinsey Quarterly:

First, there needs to be a certain structure to a situation, a certain predictability that allows you to have a basis for the intuition. If a situation is very, very turbulent, we say it has low validity, and there’s no basis for intuition. For example, you shouldn’t trust the judgments of stock brokers picking individual stocks. The second factor is whether decision makers have a chance to get feedback on their judgments, so that they can strengthen them and gain expertise. If those criteria aren’t met, then intuitions aren’t going to be trustworthy.

Klein also emphasised experience as critical: “If the experience is low, then your intuition won’t be very helpful, and you should bring in your intuitions at the end.” Additionally, time pressure, clarity of goals, and whether decisions are made individually or collaboratively influence the usefulness of intuition. In team settings, a vague “this just feels right” probably won’t cut it with your colleagues.

Fast or slow? How to hone your intuition

Ultimately, the power of intuition comes from experience and context. A chess grandmaster can spot a winning move in seconds because their subconscious has absorbed thousands of patterns over countless games. A chief firefighter who senses an imminent threat in a burning building is drawing upon years of subtle clues – many picked up without even realising it. In both cases, the environment is structured and feedback-rich. They’ll quickly find out whether they made the right call.

For a novice, those instinctive insights simply aren’t available. A gut feeling without experience is just guesswork.

The key to better intuition is knowing when it’s likely to help – and when it might mislead. Use it confidently in areas where you have genuine expertise and consistent feedback. But cautiously in unfamiliar and chaotic situations.

Malcolm Gladwell’s book Blink popularised the idea that many of our decisions are made in a heartbeat. When asked how people could sharpen their intuition, Gladwell pointed to the importance of humility. People who remain open to feedback, who learn from mistakes, and who acknowledge they don’t have all the answers tend to develop more reliable instincts over time.

“If people are part of an environment where they are provided with timely, accurate and constructive feedback, it's a lot easier to build on that knowledge base,” Gladwell said. “And it's a lot easier to be self-critical.”

Rather than picking sides in an imaginary battle between intuition and analysis, we should think of them as teammates with complementary skills. Great decision-makers know when to lean on instinct and when to slow down and think.

Need help deciding? In his book The Intuition Toolkit, Joel Pearson recommends using the acronym SMILE:

Self-awareness: If you’re feeling emotional, challenge your intuition.
Mastery: Only trust your gut in areas you know a lot about.
Impulses and addictions: Recognise that cravings and compulsions are not intuition.
Low probability: Gut feeling won’t help with statistics – use analysis instead.
Environment: Snap decisions are more suited to familiar and predictable situations.

This is the question: A bat and a ball cost $1.10. The bat costs $1 more than the ball. How much does the ball cost?
Interestingly, separate research has found that people are more likely to answer these questions correctly when reading them rather than listening to them. The takeaway? Readers are less likely to be led astray by intuition.