I was heading to Nebraska. Now there's a sentence you don't want to say too often if you can possibly help it.

At the foot of the mountain, the park ended and suddenly all was squalor again. I was once more struck by this strange compartmentalization that goes on in America -- a belief that no commercial activities must be allowed inside the park, but permitting unrestrained development outside, even though the landscape there may be just as outstanding. America has never quite grasped that you can live in a place without making it ugly, that beauty doesn't have to be confined behind fences, as if a national park were a sort of zoo for nature.

It is not as if farming brought a great improvement in living standards either. A typical hunter-gatherer enjoyed a more varied diet and consumed more protein and calories than settled people, and took in five times as much viatmin C as the average person today.

The human diet consists of just nine plants: corn, rice, wheat, potatoes, cassava, sorghum, millet, beans, barley, rye and oats.

Language is more fashion than science, and matters of usage, spelling and pronunciation tend to wander around like hemlines.

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.

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.