MANY people think that the key to success is to cultivate and doggedly maintain an optimistic outlook. This belief in the power of positive thinking, expressed with varying degrees of sophistication, informs everything from affirmative pop anthems like Katy Perry’s “Roar” to the Mayo Clinic’s suggestion that you may be able to improve your health by eliminating “negative self-talk.”
But the truth is that positive thinking often hinders us. More than two decades ago, I conducted a study in which I presented women enrolled in a weight-reduction program with several short, open-ended scenarios about future events — and asked them to imagine how they would fare in each one. Some of these scenarios asked the women to imagine that they had successfully completed the program; others asked them to imagine situations in which they were tempted to cheat on their diets. I then asked the women to rate how positive or negative their resulting thoughts and images were.
A year later, I checked in on these women. The results were striking: The more positively women had imagined themselves in these scenarios, the fewer pounds they had lost.
My colleagues and I have since performed many follow-up studies, observing a range of people, including children and adults; residents of different countries (the United States and Germany); and people with various kinds of wishes — college students wanting a date, hip-replacement patients hoping to get back on their feet, graduate students looking for a job, schoolchildren wishing to get good grades. In each of these studies, the results have been clear: Fantasizing about happy outcomes — about smoothly attaining your wishes — didn’t help. Indeed, it hindered people from realizing their dreams.
Why doesn’t positive thinking work the way you might assume? As my colleagues and I have discovered, dreaming about the future calms you down, measurably reducing systolic blood pressure, but it also can drain you of the energy you need to take action in pursuit of your goals.
In a 2011 study published in the Journal of Experimental Social Psychology, we asked two groups of college students to write about what lay in store for the coming week. One group was asked to imagine that the week would be great. The other group was just asked to write down any thoughts about the week that came to mind. The students who had positively fantasized reported feeling less energized than those in the control group. As we later documented, they also went on to accomplish less during that week.
Positive thinking fools our minds into perceiving that we’ve already attained our goal, slackening our readiness to pursue it.
Some critics of positive thinking have advised people to discard all happy talk and “get real” by dwelling on the challenges or obstacles. But this is too extreme a correction. Studies have shown that this strategy doesn’t work any better than entertaining positive fantasies.
What does work better is a hybrid approach that combines positive thinking with “realism.” Here’s how it works. Think of a wish. For a few minutes, imagine the wish coming true, letting your mind wander and drift where it will. Then shift gears. Spend a few more minutes imagining the obstacles that stand in the way of realizing your wish.
This simple process, which my colleagues and I call “mental contrasting,” has produced powerful results in laboratory experiments. When participants have performed mental contrasting with reasonable, potentially attainable wishes, they have come away more energized and achieved better results compared with participants who either positively fantasized or dwelt on the obstacles.
When participants have performed mental contrasting with wishes that are not reasonable or attainable, they have disengaged more from these wishes. Mental contrasting spurs us on when it makes sense to pursue a wish, and lets us abandon wishes more readily when it doesn’t, so that we can go after other, more reasonable ambitions.
In a recent study on healthy eating and exercise, we divided participants into two groups. Members of one group engaged in mental contrasting and then performed a planning exercise designed to help them overcome whatever obstacles stood in their way. Four months later, members of this group were working out twice as long each week as the control group and eating considerably more vegetables. In other studies, we found that people who engaged in mental contrasting recovered from chronic back pain better, behaved more constructively in relationships, got better grades in school and even managed stress better in the workplace.
Positive thinking is pleasurable, but that doesn’t mean it’s good for us. Like so much in life, attaining goals requires a balanced and moderate approach, neither dwelling on the downsides nor a forced jumping for joy.
*Gabriele Oettingen, a professor of psychology at New York University and the University of Hamburg, is the author of “Rethinking Positive Thinking: Inside the New Science of Motivation.”
A version of this op-ed appears in print on October 26, 2014, on page SR9 of the New York edition with the headline: The Problem With Positive Thinking.