Because when it comes to nutrition, life expectancy, infant and child mortality rates, and education, great progress is being made throughout the world. That is especially true of poor countries. In sub-Saharan Africa, absolute improvements in human well-being are taking place, while the quality-of-life gap with the rest of the world is also being narrowed.

According to the latest data, the share of humanity living on less than $1.90 per person per day, adjusted for purchasing power, shrunk from 42.2 percent in 1981 to 10.7 percent in 2013 (the last year for which data is available). That's a reduction of 75 percent over a comparatively short period of 32 years.

According to researchers at the Brookings Institution, "Poverty reduction of this magnitude is unparalleled in history: never before have so many people been lifted out of poverty over such a brief period of time."