Physics is really nothing more than a search for ultimate simplicity, but so far all we have is a kind of elegant messiness.

We are so used to the notion of our own inevitability as life's dominant species that it is hard to grasp that we are here only because of timely extraterrestrial bangs and other random flukes. The one thing we have in common with all other living things is that for nearly four billions years our ancestors have managed to slip through a series of closing doors every time we needed them to.

Black bears rarely attack. But here's the thing. Sometimes they do. All bears are agile, cunning and immensely strong, and they are always hungry. If they want to kill you and eat you, they can, and pretty much whenever they want. That doesn't happen often, but - and here is the absolutely salient point - once would be enough.

There'd never been a more advantageous time to be a criminal in America than during the 13 years of Prohibition. At a stroke, the American government closed down the fifth largest industry in the United States - alcohol production - and just handed it to criminals - a pretty remarkable thing to do.

Suddenly, in the space of a moment, I realized what it was that I loved about Britain - which is to say, all of it. Every last bit of it, good and bad - old churches, country lanes, people saying 'Mustn't grumble,' and 'I'm terribly sorry but,' people apologizing to ME when I conk them with a careless elbow, milk in bottles, beans on toast, haymaking in June, seaside piers, Ordnance Survey maps, tea and crumpets, summer showers and foggy winter evenings - every bit of it.

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.

But that's the glory of foreign travel, as far as I am concerned. I don't want to know what people are talking about. I can't think of anything that excites a greater sense of childlike wonder than to be in a country where you are ignorant of almost everything. Suddenly you are five years old again. You can't read anything, you have only the most rudimentary sense of how things work, you can't even reliably cross a street without endangering your life. Your whole existence becomes a series of interesting guesses.