Given the total income and wealth available in the world today, we could easily overcome poverty, which would require raising the share of the bottom half from three to roughly five percent. Unfortunately, the trend is going in the opposite direction.

I think one big improvement would be if we somehow made it cheaper and easier for developing countries to learn from the sad experience of some of the developed countries, and also from some of the positive experiences we have of building good transportation systems, like high-speed rail.

A few hundred years ago, perhaps 85 or even 90 percent of humanity lived below a standard of living that today only 40 or 45 percent fail to reach. But at that earlier time only part of this poverty could have been eradicated, and this at substantial cost not only to the pleasures of the affluent, but also to their well-being and to human culture. In our time, nearly all severe poverty could be eradicated at a cost to the affluent that is truly trivial.

Think of US slavery in 1850, or the subjection of women. Both of these injustices could have been - and were! - defended by pointing out, quite correctly, that this situation of slaves and women had been improving throughout the preceding century. Slaves, in particular, were worked less hard, beaten and raped less frequently, better fed, and less often ripped apart from their families. So would a celebration of moral progress have been appropriate in 1850? Surely not. Slavery could have been and should have been abolished - then, if not before.

It is for the poor people's sake, above all, that we urgently need more unity and better organization and need to concentrate our reform efforts in order to really to achieve reforms, one by one.

Given the total income and wealth available in the world today, we could easily overcome poverty, which would require raising the share of the bottom half from three to roughly five percent. Unfortunately, the trend is going in the opposite direction.

Over the period from 1988 to 2005, the income share of the top five percent has grown by about 3.5 percent of global household income, and the shares of all the other groups have diminished. The greatest relative reduction was in the bottom quarter, which lost about one third of its share of global household income, declining from 1.155 to 0.775 percent, and now is even more marginalized.