Ivan Petrovich Pavlov trained his dogs to respond in given ways: if the dinner bell rang, but food did not appear, they salivated. This prompts the observation that there is a lot of Pavlovian conditioning in America these days.

The most unnerving, if least cosmic, concerns David Letterman, the CBS late-night television host. Last week on his show, he revealed that he had had affairs with an unspecified number of staff members and that somebody was trying to shake him down for $2m to keep it quiet. Later, a CBS producer was arrested and charged with attempted extortion.