“The most powerful driver of immigration is having a stock of the diaspora already in the country because migration from a poor country to a rich one is daunting, it’s costly, and the poorest people can’t move. So what we get is people leaving countries where they have some money, but where they have good connections. And so as the migration builds up a stock of the diaspora, that’s why migration accelerates.”
“Some diversity is good. It gives the society more innovation, gives it more variety. But if you have too much diversity, trust starts to erode; cooperation erodes; generosity erodes. And so there is a right amount of diversity. I can’t tell you how much the right amount is, but that’s what every society’s got to antagonise about.”
* See here for audio/video feeds of a lecture given by Collier to the LSE recently on the topic
'Exodus: immigration and multiculturalism in the 21st century'.