What kind of people are going to live in these cities that will be growing so quickly the next couple decades? Will retirees want to be in them? Families? Or will they have to flee because they won’t be able to afford them? Hoornweg: All of the above. With good city management, a city is attractive to everybody. There are really interesting studies coming out of the Santa Fe institution that basically say that if there were no externalities for traffic or whatever, the human population would like to live in one city, because we really like being with each other.