Social enterprises can become easily distracted building and managing their business instead of focusing on the problem they are trying to solve -- even if the solution involves running a healthy business.
The rescue of the bottom billion is only a reality if Mr. Sachs and Mr. Easterly put their outstanding intellectual skills to work instead of trying to win a debate that academics will perpetuate so long as they exist.
Leading lights of the aid movement -- Geldof, Bono, Sachs and Easterly -- continue to bicker with politicians and amongst themselves without taking a visible role in reform of the levers of assistance.
Calling 63 countries "potentially well governed" is like saying Paris Hilton is potentially a virgin; ignoring bad government is a formula for the same kind of bad aid policy that produced decades of failure.
Sub-Saharan Africa faces a constellation of special challenges, with greater or lesser impact in different parts of the region. These challenges should be addressed forthrightly and in an integrated manner.