Though people could, in principle, cross national borders to reach places where their work is more highly rewarded, they are in fact prevented from doing so. As a result, huge differences also persist in the price of labor, as you can see when you get a haircut in rural India or hire a driver or babysitter in Bolivia. You can easily buy such services at one-fiftieth the price you would pay in London, Hamburg or Manhattan.

With the Health Impact Fund, the innovation is paid for separately, through publicly funded health impact rewards, and the product is sold at the cost of production to all. Here, the cruel injustice of preventing the poor from buying at cost - evidenced by today's suppression of the trade in generic versions of patented medicines - would no longer be needed.

The global financial crisis is a great opportunity to showcase and propagate both causal and moral institutional analysis. The crisis shows major flaws in the way the US financial system is regulated and, more importantly, in our political system, which is essentially a bazaar of legalized bribery where financial institutions can buy themselves the governmental regulations they want, along with the regulators who routinely receive lucrative jobs in the industry whose oversight had formerly been their responsibility, the so-called revolving-door practice.

By using general consumption PPPs, the World Bank is, in effect, saying to the poor: "Sure, you cannot buy as much food as the dollar value we attribute to your income would buy in the United States. But then you can buy much more by way of services than you could buy with this PPP equivalent in the United States." But what consolation is this? The poor do not buy services - they are services, on their luckier days.

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.

Domestic power structures are shaped in good part by global arrangements.

The bottom half of humanity is living in severe poverty; not all of them are malnourished or severely deprived now, but they are extremely vulnerable to even small upsets in their income or in the prices they face of basic necessities, and when something like this happens, they can be thrown off kilter in terms of a disease of a family member or a change in food prices; anything like that can throw them into destitution.