According to the article, “Both groups [the United Nations and the IIASA] foresee India becoming the world’s most populous country, with its numbers peaking around 2070 and declining to around 1.5 or 1.6 billion by 2100. Where they differ most is in their estimates of the coming population decline in China and of the coming population explosion in Africa south of the Sahara—where most of the world’s growth is going to occur.” Why do the groups, the United Nations and the IIASA, differ on their projections for the growth of the world’s population, and how much uncertainty exists?

i do agree with robert moses’ statements about wiping out cities that are an “impediment to new growth”. in order to have a positive community, the city must continue to grow either in terms of size or economics. therefore wiping out cities that restrict growth benefits the overall society and all the people living in it. similar to a social contract, i believe that if a person was to live in a community they must sacrifice some of their rights, in this case property, for the overall good of the people. as long as these people living in the cities are reimbursed and the purpose of wiping out the cities is to serve the public, there is no problem with robert moses’ core idea.