Out of the thirty thousand types of edible plants thought to exist on Earth, just eleven—corn, rice, wheat, potatoes, cassava, sorghum, millet, beans, barley, rye, and oats—account for 93 percent of all that humans eat, and every one of them was first cultivated by our Neolithic ancestors.

There are things you just can't do in life. You can't beat the phone company, you can't make a waiter see you until he's ready to see you, and you can't go home again.

Clearly, some time ago makers and consumers of American junk food passed jointly through some kind of sensibility barrier in the endless quest for new taste sensations. Now they are a little like those desperate junkies who have tried every known drug and are finally reduced to mainlining toilet bowl cleanser in an effort to get still higher.

I ordered a coffee and a little something to eat and savored the warmth and dryness. Somewhere in the background Nat King Cole sang a perky tune. I watched the rain beat down on the road outside and told myself that one day this would be twenty years ago.

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.

That's the trouble with losing your mind; by the time it's gone, it's too late to get it back.

There is no such thing, incidentally, as one kudo.