Instinct and Decision Making: When "Going with Your Gut" Spells Trouble

"I rely on myself very much," Donald Trump has said, "I just think that you have an instinct and you go with it." There is certainly a place for instinct or intuition in decision making. Malcolm Gladwell popularized this notion in his 2005 book, Blink. Unfortunately the subtitle of that book - "The Power of Thinking Without Thinking" - led many to conclude that intuition can substitute for study, knowledge and experience. Even Gladwell acknowledged that the former must draw on the latter.

So, relying on your instincts, your intuitive responses, can be tricky. Write down the first answer that comes into your mind for the following problem. Don't read further until you have done this:

A bat and ball cost $1.10. If the bat costs one dollar more than the ball, how much does the ball cost?

If you answered ten cents, you are in very good company. More than 80 percent of students at most colleges agree with you, as do more than 50 percent of students at Harvard, Princeton, and MIT. Yet, the correct answer is five cents ($ .05 plus $1.05 = $1.10).

In his fascinating 2011 book, Thinking, Fast and Slow, Nobel behavioral economist Daniel Kahneman uses this exercise to highlight the fact that our gut response, our intuition, can cause problems. There is, he argues, an important difference between two ways we think. Our fast system (System 1) uses our mental models (heuristics) to come up with quick answers. In routine situations, these mental models or instincts work, saving us time and effort. But our slow system (System 2), where we question assumptions and engage in more careful and logical thinking, is sometimes needed. The baseball and bat problem is an example of that.

Using System 1 thinking on a System 2 problem doesn't work. In 2003, Vice-President Dick Cheney, no doubt with a mental model about American power and American values in mind, said that U.S. forces would be "greeted as liberators" when they overthrew Saddam Hussein, that the war would go "relatively quickly," and that this victory would spark a wave of democratization across the Middle East. Clearly, intuition failed. His instincts hid some very faulty assumptions and ignored some essential information about the Middle East.

The Vietnam War was pursued on the intuitive notion that the loss of South Vietnam would cause a "domino effect." Other Southeast Asia nations would fall to communism. They didn't. Writing years later in In Retrospect: The Tragedy and Lessons of Vietnam, former Defense Secretary Robert McNamara said that "Our misjudgments of friend and foe alike reflected our profound ignorance of the history, culture, and politics of the people in the area, and the personalities and habits of their leaders . . . We failed to analyze our assumptions critically, then or later. The foundations of our decision making were gravely flawed."

This, of course, is hardly just a recent problem. As the Civil War loomed, the North "knew" the South lacked the resources to put up much of a fight, just as the South "knew" that the North lacked the stomach for a protracted conflict. Nor is it just an American problem. Napoleon trusted his instincts and ended up losing his army in the Russian winter. Adolph Hitler routinely discounted the advice of his generals, trusting in his instincts. For a while, he seemed brilliant and unstoppable, until that intuition led him into Russia, where he repeated Napoleon's mistake.

Intuition, when grounded in objective data and using System 2 thinking, can be helpful. But when data are not sought, not carefully evaluated, or are discounted, and when assumptions are not tested, failure awaits. This is where our new president - and any decision maker - needs to be careful. As a candidate and now president-elect, Donald Trump has exhibited a disturbing tendency to over-rely on his instincts. He has claimed that vaccination causes autism, despite the weight of scientific evidence. He believes that global warming is a "hoax," without considering the evidence of thousands of studies to the contrary. He "knows" he won the popular vote because three million fraudulent votes went to Hillary Clinton, without data to back this up. He discounted the joint intelligence assessment that Russia directed a campaign to interfere with the American election because "They have no idea if it's Russia or China or somebody. It could be somebody sitting in a bed some place."

In our daily lives, filled as they are with challenges and problems to be solved, we like to think of ourselves as smart, with good instincts. Going with our "gut" has served us so well in the past (though we tend to forget when it has not). But when we don't do our homework first, our intuition can fail. In our personal lives, the damage might be limited. For leaders, the consequences can be catastrophic.