It is tough being an optimist these days.
First, I had a conversation with a journalist yesterday who was looking to write a story which challenged the claim by Bill Gates in his annual letter that "By 2035 there will be almost no poor countries in the world".
Mr. Gates is possibly correct if GDP per capita increases at about 3.5% for 20 years straight. That will double GDP/capita by 2035 and so for countries that are at $500 per capita income they will get to the approximately $1000 threshold for what the World Bank classifies as "low income".
These are difficult and challenging targets but not ridiculous ones. However, countries that are no longer classified as "low income" contain a lot of poor people (with India and the obvious case in point).
So even with increasing growth-poverty elasticities in Africa and better governance (and the majority of the countries Mr Gates is talking about are from this region), poverty will certainly not be abolished by 2035 although I believe it will be much much lower than it is now.
Second, Angus Deaton--one of my heroes--has, I think, been unfair on Jeff Sachs in his Lancet review of Nina Munk's book "The Idealist: Jeffrey Sachs and the Quest to End Poverty".
The basic critique of the Millennium Village Project initiative is: (a) it is an untested approach which is unlikely to work beyond the initial "sugar rush" of funds because it was conceived of outside of the contexts it is supposed to operate within, (b) the approach is not being properly evaluated --either for short term or long run effects and (c) it is the brainchild of Jeff Sachs who you either love or hate (neither for me).
But the review by Angus Deaton is too dismissive of the MVP idea in the absence of evidence (evidence we all believe should have been collected--see this letter from Bump, Clemens, Demombynes and me from the Lancet in 2012).
We should critique Jeff Sachs for not investing in evaluation (because perhaps he has such strong beliefs about the MVP--who know why?) but then you cannot dismiss the MVP idea in the absence of evidence simply because you also have strong beliefs on the other side.
Of course we need different blends of idealism, realism, optimism and pessimism for different challenges, contexts and times. Balance is key and in the weak accountability world inhabited by international development that is perhaps the most difficult thing to be optimistic about.