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.

There is at the global level a very small number of actors who can meaningfully weigh in on global institutional design, who are able - through powerful governments and most effectively through the government of the United States - to exert substantial influence on international negotiations, which are routinely conducted behind closed doors.

I think that many citizens understand how our system works, or rather, fails to work, for structural reasons. But who has the capacity and the incentives to bring change? The banks and other corporations love the system because it allows them to buy legislation that serves their own interests even at the expense of the vast majority of citizens. Incumbent politicians love the system because it allows them to raise millions of dollars toward defending their seats.

It is irrational to charge high prices for socially valuable innovations as this guarantees that they will be underutilized. It is much better to sell them at cost and then to reward the innovator in some other way. This is not always possible, because in some cases the value of an innovation is in the eye of the beholder; it's very difficult to value how much a new Madonna song is worth, for example. But in the case of medicines, green technologies and seeds in agriculture, such an alternative reward mechanism is fairly straightforward.

In order to prepare for meaningful change, we have to look at both sides of the problem. We need to examine the output of our political system, which is often very hostile to the poor abroad and hostile also to the poor and middle class domestically. And we must also look at the procedures through which this output is produced.

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.

The bottom quarter of the human population has only three-quarters of one percent of global household income, about one thirty-second of the average income in the world, whereas the people in the top five percent have nine times the average income. So the ratio between the averages in the top five percent and the bottom quarter is somewhere around 300 to one - a huge inequality that also gives you a sense of how easily poverty could be avoided.