Car prices play a large role in calculating PPPs even while they play no role whatsoever in the consumption or consumption needs of the poor. And the prices of rice, bread and beans play a small role in calculating PPPs even though they play a huge role in meeting the consumption needs of the poor. So the World Bank's method of comparing and converting everything at general purchasing power parities into US dollars is highly distorting within an exercise whose purpose it is to determine whether households are or are not capable of meeting their basic consumption needs.

We should not think of poverty eradication as a matter of collecting money and giving it to the poor so much as of reforming the global rules that are disadvantaging the poor and making it impossible for them to fend for themselves.

Poverty persists, essentially, because the people at the bottom - the bottom quarter and also the bottom half - see the gains from the rising global average income wiped out by severe declines in their relative share.

The fact that oppressive and corrupt regimes can borrow money in the name of the whole country means that the country's future generations will be weighed down by interest and repayment burdens, even if the money has been frittered away in some frivolous way, embezzled or used for weapons to suppress the country's population.

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.

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.

Social rules are susceptible to moral analysis. This is, again, relatively familiar in the domestic case, where we now condemn slavery as unjust. And when we affirm this judgment, we're not merely saying that all those people who owned slaves were unethical people; they shouldn't have done that. We do believe this, but that's only part of the point. We also believe that the fugitive slave laws were unjust.