But I got a great deal else from the experience. I learned to pitch a tent and sleep beneath the stars. For a brief, proud period I was slender and fit. I gained a profound respect for the wilderness and nature and the benign dark power of woods. I understand now, in a way I never did before, the colossal scale of the world. I found patience and fortitude that I didn't know I had. I discovered an America that millions of people scarcely know exists. I made a friend. I came home.

Geologists are never at a loss for paperweights.

Physicists are atoms' way of thinking about atoms.

When the poet Paul Valery once asked Albert Einstein if he kept a notebook to record his ideas, Einstein looked at him with mild but genuine surprise. "Oh, that's not necessary," he replied . "It's so seldom I have one.

Christmas tree stands are the work of the devil and they want you dead.

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.

If you can imagine a man having a vasectomy without anesthetic to the sound of frantic sitar-playing, you will have some idea of what popular Turkish music is like.