A world with a sudden limit on air travel would be tremendously different from the one we live in now.

In 1491 the Inka ruled the greatest empire on earth. Bigger than Ming Dynasty China, bigger than Ivan the Great’s expanding Russia, bigger than Songhay in the Sahel or powerful Great Zimbabwe in the West Africa tablelands, bigger than the cresting Ottoman Empire, bigger than the Triple Alliance (as the Aztec empire is more precisely known), bigger by far than any European state, the Inka dominion extended over a staggering thirty-two degrees of latitude—as if a single power held sway from St. Petersburg to Cairo.

Historically, large-scale global trade has served two functions: 1) the exchange of goods between willing sellers and buyers described in Econ 101 textbooks; 2) as a tool of state aggrandizement, in which the private parties are stand-ins for governmental interests.

Compared with U.S. cities, Japanese cities bend over backward to help foreigners. The countryside is another matter.

The way I think of it, economics and ecology occupy two intellectual silos, isolated from each other. Even when they do take each other into consideration, it's not uncommon for ecologists to spout absolute nonsense about economics, and vice versa.

The human propensity is to believe that flukes of good fortune will never come to an end.

The Japanese are great at inventing complex systems of rules, and not so great at explaining those rules to foreign visitors.