If I asked you to judge how smart someone is, you’d know where to start. But if you were going to assess how wise that person is, what qualities would you consider?

Wisdom is the ability to make sound judgments and choices based on experience. It’s a virtue according to every great philosophical and religious tradition, from Aristotle to Confucius and Christianity to Judaism, Islam to Buddhism, and Taoism to Hinduism. According to the book From Smart to Wise, wisdom distinguishes great leaders from the rest of the pack. So what does it take to cultivate wisdom?

In an enlightening study led by psychologists Paul Baltes and Ursula Staudinger, a group of leading journalists nominated public figures who stood out as wise. The researchers narrowed the original list down to a core set of people who were widely viewed as possessing wisdom—an accomplished group of civic leaders, theologians, scientists, and cultural icons. They compared these wise people with a control group of professionals who were successful but not nominated as wise (including lawyers, doctors, teachers, scientists, and managers).

Both groups answered questions that gave them a chance to demonstrate their wisdom. For example, what advice would they give to a widowed mother facing a choice between shutting down her business and supporting her son and grandchildren? How would they respond to a call from a severely depressed friend? A panel of experts evaluated their answers, and the results—along with several follow-up studies—reveal six insights about what differentiates wise people from the rest of us.

1. Don’t wait until you’re older and smarter. The people with the highest wisdom scores are just as likely to be 30 as 60. It turns out that the number of life experiences has little to do with the quality of those experiences. According to the data, between ages 25 to 75, the correlation between age and wisdom is zero. Wisdom emerges not from experience itself, but rather from reflecting thoughtfully on the lessons gained from experience. Further research shows that intelligence only accounts for about 2% of the variance in wisdom. It’s possible to be quick on your feet and skilled in processing complex information without reaching sensible solutions to problems. Cultivating wisdom is a deliberate choice that people can make regardless of age and intelligence. Here’s how they do it.

2. See the world in shades of grey, not black and white. Imagine meeting a 15-year-old girl who plans to get married next week. What would you tell her?

Here’s a response that scored low in wisdom:

“A 15-year-old girl wants to get married? No, no way, marrying at age 15 would be utterly wrong. One has to tell the girl that marriage is not possible. (After further probing) It would be irresponsible to support such an idea. No, this is just a crazy idea.”

In contrast, wise people embraced nuance and multiple perspectives. Consider one answer that received high marks for wisdom:

“Well, on the surface, this seems like an easy problem. On average, marriage for 15-yearold girls is not a good thing. But there are situations where the average case does not fit. Perhaps in this instance, special life circumstances are involved, such that the girl has a terminal illness. Or the girl has just lost her parents. And also, this girl may live in another culture or historical period. Perhaps she was raised with a value system different from ours. In addition, one has to think about adequate ways of talking with the girl and to consider her emotional state.”

Wise people specialize in what strategy expert Roger Martin calls integrative thinking—"the capacity to hold two diametrically opposing ideas in their heads”—and reconcile them for the situation at hand. In the words of the philosopher Bertrand Russell, “fools and fanatics are always so certain of themselves, but wiser people so full of doubts.”

3. Balance self-interest and the common good. A second defining quality of wisdom is the ability to look beyond our personal desires. As psychologist Robert Sternberg puts it: “wisdom and egocentricity are incompatible… people who have gotten where they are by not taking other people's interests into account or even by actively thwarting the interests of others… would not be viewed as wise.”

This doesn’t mean that wise people are self-sacrificing. In Give and Take, I report evidence that well-being and success both suffer if we’re too focused on others or on ourselves. It’s neither healthy nor productive to be extremely altruistic or extremely selfish. People who fail to secure their oxygen masks before assisting others end up running out of air, and those who pursue personal gains as the expense of others end up destroying their relationships and reputations. Wise people reject the assumption that the world is a win-lose, zero-sum place. They find ways to benefit others that also advance their own objectives.

4. Challenge the status quo. Wise people are willing to question rules. Instead of accepting things as they have always been, wisdom involves asking whether there’s a better path. In Practical Wisdom, psychologist Barry Schwartz and political scientist Kenneth Sharpe describe a Philadelphia man who was convicted of holding up a taxi driver with a gun. The sentencing guidelines called for two to five years in jail, but the facts of case didn’t fit: the man used a toy gun, it was his first offense, he had just lost his job, and he stole $50 to support his family. A wise judge gave him a shorter sentence and permission to hold a job outside of jail during the day so that he could take care of his family—and required him to repay the $50.

5. Aim to understand, rather than judge. By default, many of us operate like jurors, passing judgment on the actions of others so that we can sort them into categories of good and bad. Wise people resist this impulse, operating more like detectives whose goal is to explain other people’s behaviors. As psychologist Ellen Langer is fond of saying, “Behavior makes sense from the actors’ perspective, or else they wouldn’t do it.” Over time, this emphasis on understanding rather than evaluating yields an advantage in predicting others’ actions, enabling wise people to offer better advice to others and make better choices themselves.

6. Focus on purpose over pleasure. In one surprising study, Baltes’ team discovered that wise people weren’t any happier than their peers. They didn’t experience more positive emotions, perhaps because wisdom requires critical self-reflection and a long-term view. They recognized that just as today’s cloud can have a silver lining tomorrow, tomorrow’s silver lining can become next month’s suffering. However, there was a clear psychological benefit of wisdom: a stronger sense of purpose in life. From time to time, wisdom may involve putting what makes us happy on the back burner in our quest for meaning and significance.

On the way to success, many people pursue money and power over wisdom. As Benjamin Franklin once wrote:

“Who is wise? He that learns from everyone.

Who is powerful? He that governs his passions.

Who is rich? He that is content.

Who is that? Nobody.

But a truly wise person would refuse to accept that conclusion.

For more on balancing self-interest and the common good, see Adam's book Give and Take: A Revolutionary Approach to Success, a New York Times and Wall Street Journal bestseller. Follow Adam here by clicking the FOLLOW button above and on Twitter @AdamMGrant