Appealing for peace 50 years ago, President John F. Kennedy told the Irish Parliament, “The problems of the world cannot possibly be solved by skeptics or cynics, whose horizons are limited by the obvious realities. We need men who can dream of things that never were and ask, why not?”

Today, more and more people are dreaming of a world free of poverty.

In April, the Development Committee of the World Bank set the goal of ending extreme poverty by the year 2030. More recently, the United Nations General Assembly working group on global goals concluded that “eradicating poverty in a generation is an ambitious but feasible goal.” As one who wrote in 2005 that ours was the generation that could end extreme poverty, I am pleased to see this idea take hold at the highest levels.

Are these errant dreams as the world barrels toward more confusion, conflict and climate change, or is there something substantial in the recent wave of high-level interest in the idea? The evidence is on the side of the optimists. And the evidence also supports both those who favor more markets and those who favor more public-private strategies. It’s all a matter of context.

The global picture will surprise doomsayers. According to the World Bank’s scorecard, the proportion of households in developing countries below the extreme-poverty line (now measured as $1.25 per person per day at international prices) has declined sharply, from 52 percent in 1980, to 43 percent in 1990, 34 percent in 1999, and 21 percent in 2010. Even sub-Saharan Africa, the region with the most recalcitrant poverty, is finally experiencing a notable decline, from 58 percent in 1999 to 49 percent in 2010.