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

The Japanese drive on the left side of the road. Most streets literally do not have names.

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.

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

The embrace of a new technology by ordinary people leads inevitably to its embrace by people of malign intent.

Major power and telephone grids have long been controlled by computer networks, but now similar systems are embedded in such mundane objects as electric meters, alarm clocks, home refrigerators and thermostats, video cameras, bathroom scales, and Christmas-tree lights - all of which are, or soon will be, accessible remotely.

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