From The Economist:
A HUNDRED-DOLLAR BILL is lying on the ground. An economist walks past it. A friend asks the economist: “Didn’t you see the money there?” The economist replies: “I thought I saw something, but I must have imagined it. If there had been $100 on the ground, someone would have picked it up.”
If something seems too good to be true, it probably is not actually true. But occasionally it is. Michael Clemens, an economist at the Centre for Global Development, an anti-poverty think-tank in Washington, DC, argues that there are “trillion-dollar bills on the sidewalk”. One seemingly simple policy could make the world twice as rich as it is: open borders.
Workers become far more productive when they move from a poor country to a rich one. Suddenly, they can join a labour market with ample capital, efficient firms and a predictable legal system. Those who used to scrape a living from the soil with a wooden hoe start driving tractors. Those who once made mud bricks by hand start working with cranes and mechanical diggers. Those who cut hair find richer clients who tip better.
“Labour is the world’s most valuable commodity—yet thanks to strict immigration regulation, most of it goes to waste,” argue Bryan Caplan and Vipul Naik in “A radical case for open borders”.