Scientists have established huge numbers of links between particular diseases and snippets of DNA, but in the great majority of cases, this has not yet been translated into treatments that can help cure patients. These treatments will come - tomorrow, or the day after.

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

Smartphones can relay patients' data to hospital computers in a continuous stream. Doctors can alter treatment regimens remotely, instead of making patients come in for a visit.

A whole bunch of big technological shocks occurred when Asian innovations - paper, gunpowder, the stirrup, the moldboard plow and so on - came to Europe via the Silk Road.

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.

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

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