I won't compare ants and people, but ants give us a useful model of how single members of a community can become so organized that they end up resembling, in effect, one big collective brain. Our own exploding population and communication technology are leading us that way.

Mistakes are at the very base of human thought, embedded there, feeding the structure like root nodules. If we were not provided with the knack for being wrong, we could never get anything useful done. We think our way along by choosing between right and wrong alternatives, and the wrong choices have to be made as often as the right ones. We get along in life this way.

We still think of human disease as the work of an organized, modernized kind of demonology, in which the bacteria are the most visible and centrally placed of our adversaries. We assume that they must somehow relish what they do.

I do not understand modern physics at all, but my colleagues who know a lot about the physics of very small things, like the particles in atoms, or very large things, like the universe, seem to be running into one queerness after another, from puzzle to puzzle.

My mitochondria comprise a very large proportion of me. I cannot do the calculation, but I suppose there is almost as much of them in sheer dry bulk as there is the rest of me. Looked at in this way, I could be taken for a very large, motile colony of respiring bacteria, operating a complex system of nuclei, microtubules, and neurons for the pleasure and sustenance of their families, and running, at the moment, a typewriter.

I don't want to be reincarnated, that's for sure. When you've had rewarding experiences in your life - a loving family, friends - you don't need additional reassurances that you're going to do something with a new cast of characters. I'd just as soon pass.

It is from the progeny of this parent cell that we all take our looks; we still share genes around, and the resemblance of the enzymes of grasses to those of whales is in fact a family resemblance.