In Matthew 26:11, Jesus says, "The poor you will always have with you." Christians like to argue about what he meant, but here's something Jesus might recommend:

Reading the clear, calm and revelatory book "Poor Economics," from Abhijit Banerjee and Esther Duflo. It is gloriously instructive, and bracing testimony in itself to the gold standard of the Enlightenment: the scientific method.

The authors, both economists at MIT, spent 15 years in the field, running randomized controlled trials to test various approaches to combating poverty. They bring both rigor and humility to a predicament typically riven by ideology and blowhards.

The authors define the poor as those living on 99 cents or less each day, some 585 million in 2005, about 13 percent of the world.

"What is striking is that even people who are that poor are just like the rest of us in almost every way," they report. "We have the same desires and weaknesses; the poor are no less rational than everyone else -- quite the contrary. Precisely because they have so little, we often find them putting careful thought into their choices. They must be sophisticated economists just to survive. Yet our lives are as different as liquor and liquorice."

The reasons are multiple and surprising -- without clean water, Social Security, a safe place to store money, immunizations and the ability to read the news, life is perilous and booby-trapped. Those supports -- nearly invisible in the daily lives of Europeans and North Americans -- make our secure existence possible.

Now consider intestinal parasites in Kenya. "Kids in Kenya who were treated for their worms at school for two years, rather than one (at the cost of $1.36 per child per year) earned 20 percent more as adults every year," or some $3,269 over a lifetime.

This modest intervention is unsexy, but truly potent. Banerjee and Duflo are just as keen about examining the tactics that fail, including one in which the authors tried to encourage public nurses to show up to their jobs -- a chronic difficulty in rural India -- by docking pay. After an initial burst of compliance, attendance was made worse as nurses figured out just how willing their supervisors were to look away.

Here are tough lessons, and "Poor Economics" serves them up. Offering a discrete amount of food helps poor families finish complete their cycles of immunizations, and pays for itself in efficiency. Micro-lending, despite its explosive-growth, isn't for everyone, partly because not all people are entrepreneurial.

This makes for refreshing fare in a debate frequently caught between the polarized views of Jeffrey Sachs and William Easterly.

Sachs argued in "The End of Poverty" that the rich countries can vanquish global destitution with a $195 billion infusion of foreign aid; Easterly's "The White Man's Burden" sees aid doing more harm than good -- corrupting local institutions and preventing people from finding solutions of their own.

By contrast, "Poor Economics" moves case by trial-tested case to ask when and where a tactic helped, and when and where it hurt. India is still haunted by Sanjay Gandhi's aggressive sterilization campaign in the mid-1970s, which engendered the memorable 1977 political slogan against his mother: "Get rid of Indira and save your penis." To this day, pockets of Indian slum-dwellers resist polio drops, believing they will secretly sterilize children.

"Small changes can have big effects," the authors write. Banerjee has advised the government of India and the World Bank, and Duflo won a MacArthur Genius grant in 2009. She was also chosen last week as one of Time Magazine's most influential people.



For readers disheartened by the revelations of falsehood in "Three Cups of Tea," the timing is perfect for "Poor Economics." It welcomes us to the grown-up table.