“Just go with your gut.” This is a piece of advice everyone has heard at some decision-making stage of their lives. The gut, in this case, means the opposite of reason. It’s something we tend to consider as an elaborate remnant of our animal instinct. When we are told to rely on intuition, it is an invitation to check in with our emotions and to stop worrying, for a moment, about whether something we feel can be explained factually. Still, in many cases, snap judgments amount to plain old bias. When, if ever, should we trust our guts over our heads? Can we opt out of our instinctive reactions?

To answer that question, it is key to understand how our intuition works in the first place. Gut reactions happen when our brain is on autopilot, to help us process all the information we r...