Severe poverty is getting better by some measures, but it's also becoming ever more scandalous because it is now so easily avoidable.

Each powerful player, or coalition of players, will make concessions in areas where it has relatively less at stake in exchange for other such players making reciprocal concessions in other areas where it has relatively more at stake. Such trades are collectively rational insofar as they get each of the powerful players more of what it wants. But such trades are also dangerous because the whole international rule-system will become incoherent and therefore vulnerable to crises that will continue to become increasingly severe.

To make a proper moral appraisal of the prevalence of severe poverty today, we should focus not on comparisons with times past, when the global average income was much lower, but on a comparison with what would be possible in our time, given the current global average income and level of technological and administrative development.

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.

Feudalism is an economic system where a few people own all the land and the others have no option but to be serfs on such a feudal estate. We now condemn feudalism. We condemn not merely the feudal lords but we condemn the whole structure of rules that sustained feudalism. I am asking people to think similarly about the world economy.

One citizen, or a few, may be powerless if all the rest are determined to benefit from the imposition of unjust supranational rules. But this excuse cannot work for large numbers. Just imagine 10 million US citizens saying in unison: "I am just one powerless citizen. There is nothing I can do to change my government's policies!"

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.