I don’t know about you, but I feel strongly that policy makers sitting in Washington D.C. think tanks won’t solve our biggest social problems, whether it’s education reform or malnutrition. Top-down thinking should be a Cold War-era relic. By contrast, social entrepreneurs are solving big problems from the bottom up, with a lot of what I call “little bets,” or low-risk actions taken to discover, develop, and test ideas.

The subject of the new film “To Catch a Dollar,” Grameen Bank founder Muhammad Yunus is one of the best-known examples of a person who has made a series of little bets to build up to a groundbreaking innovation. Like any effective entrepreneur (social or otherwise), the way he discovered what problems to solve was to get out of his office and into the world.

In 1974, Yunus taught economics at Chittagong University in Bangladesh. That year, a severe famine ravaged India, sending starving people from the countryside into cities in search of food. Yunus began to dread his own lectures. “What good were all my complex theories when people were dying of starvation on the sidewalks and porches outside my lecture hall?” he asked himself. “Nothing in the economic theories I taught reflected the life around me.” So he decided to do something quite unconventional: Yunus the economist became Yunus the anthropologist.

In the village of Jobra, a small town outside Chittagong, Yunus absorbed himself in the lives of some of India’s poorest people, seeking to understand poverty from what he called the “worm’s-eye view.” He spent time with women who separated rice from straw with their bare feet ten hours per day. He toiled with farmers in the fields to try to help them improve their irrigation systems and crop yields. And he went from home to home to understand how people made their living. The insights he gained informed his little bets. “I tried a great number of things,” Yunus wrote, “Some worked. Others did not.”

Helping a small group of farmers improve their crop yields, for example, only went so far. The impact was relatively small. What kept people in poverty wasn’t a lack of effort. In the end, he found that it was a lack of formal credit. Poor people who could not get a conventional loan relied on high-interest-rate loans from middlemen to buy needed supplies, leaving them just enough profit to survive from day to day.

Yunus never intended to be a moneylender. By immersing himself in the lives of the poor, he discovered a core problem that others had overlooked.

Yunus’ approach, as well as the approach taken by Teach for America’s Wendy Kopp, and leaders at KIVA and KIPP Schools, provide important lessons for us all. The crux of our social problems can only be understood at the worm’s-eye view. We can only discover answers and solutions through hundreds, if not thousands, of little bets.

One can only hope that policy makers will soon see the light and look to social entrepreneurs for the right questions and the right answers.