Lewis Thomas

The uniformity of the earth's life, more astonishing than its diversity, is accountable by the high probability that we derived, originally, from some single cell, fertilized in a bolt of lightning as the earth cooled.

In the fields I know best, among the life sciences, it is required that the most expert and sophisticated minds be capable of changing course - often with a great lurch - every few years.

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.

My father was a doctor, and I admired him and got along well with him. He took me with him on house calls. We were living in Flushing, which was then a sleepy village of 25,000 - before the subway got there. I've been sure I wanted to be a doctor since I was about 12.

We can take some gratification at having come a certain distance in just a few thousand years of our existence as language users, but it should be a deeper satisfaction, even an exhilaration, to recognize that we have such a distance still to go.

Survival, in the cool economics of biology, means simply the persistence of one's own genes in the generations to follow.

We carry stores of DNA in our nuclei that may have come in, at one time or another, from the fusion of ancestral cells and the linking of ancestral organisms in symbiosis. Our genomes are catalogues of instructions from all kinds of sources in nature, filed for all kinds of contingencies.

Having long suspected that there was something alive in there, running the place, separate from everything else, absolutely individual and independent, we've celebrated by giving it a real name. My self.

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.

Once you have become permanently startled, as I am, by the realization that we are a social species, you tend to keep an eye out for the pieces of evidence that this is, by and large, good for us.

We are not like the social insects. They have only the one way of doing things and they will do it forever, coded for that way. We are coded differently, not just for binary choices, go or no-go. We can go four ways at once, depending on how the air feels: go, no-go, but also maybe, plus what the hell let's give it a try.

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.