When you sit in a chair, you are not actually sitting there, but levitating above it at a height of one angstrom (a hundred millionth of a centimetre), your electrons and its electrons implacably opposed to any closer intimacy.

My favourite fellow of the Royal Society is the Reverend Thomas Bayes, an obscure 18th-century Kent clergyman and a brilliant mathematician who devised a complex equation known as the Bayes theorem, which can be used to work out probability distributions. It had no practical application in his lifetime, but today, thanks to computers, is routinely used in the modelling of climate change, astrophysics and stock-market analysis.

18th century scientists, the French in particular, seldom did things simply if an absurdly demanding alternative was available.

For a long time, I'd been vaguely fascinated by the idea that Charles Lindbergh flew the Atlantic and Babe Ruth hit 60 home runs in the same summer.

Entirely incidentally, a little-known fact about Shakespeare is that his father moved to Stratford-upon-Avon from a nearby village shortly before his son's birth. Had he not done so, the Bard of Avon would instead be known as the rather less ringing Bard of Snitterfield.

There is more difference between a zebra and a horse, or between a dolphin and a porpoise, than there is between you and the furry creatures your distant ancestors left behind when they set out to take over the world.

So here I am, my affections torn between a postal service that never feeds me but can tackle a challenge and one that gives me free tape and prompt service but won't help me out when I can't remember a street name. The lesson to draw from this, of course, is that when you move from one country to another you have to accept that there are some things that are better and some things worse, and there is nothing you can do about it. That may not be the profoundest of insights to take away from a morning's outing, but I did get a free doughnut as well, so on balance I guess I'm happy.