Lewis Thomas

We leave traces of ourselves wherever we go, on whatever we touch.

Our behavior toward each other is the strangest, most unpredictable, and most unaccountable of all the phenomena with which we are obliged to live. In all of nature, there is nothing so threatening to humanity as humanity itself.

Some of the shrewdest insight into natural processes have been greeted at the outset by the exclamation 'But that's ridiculous'.

Viewed from the distance of the moon, the astonishing thing about the earth, catching the breath, is that it is alive. ... It has the organized, self-contained look of a live creature, full of information, marvelously skilled in handling the sun

All of today's DNA, strung through all the cells of the earth, is simply an extension and elaboration of [the] first molecule.

The gift of language is the single human trait that marks us all genetically, setting us apart from the rest of life.

It is almost always a greater pleasure to come across a semicolon than a period. The period tells you that that is that; if you didn't get all the meaning you wanted or expected, anyway you got all the writer intended to parcel out and now you have to move along. But with a semicolon there you get a pleasant little feeling of expectancy; there is more to come; read on; it will get clearer.

Although I usually think I know what I'm going to be writing about, what I'm going to say, most of the time it doesn't happen that way at all. At some point I get misled down a garden path, I get surprised by an idea that I hadn't anticipated getting, which is a little bit like being in a laboratory.

As a people, we have become obsessed with Health. There is something fundamentally, radically unhealthy about all this. We do not seem to be seeking more exuberance in living as much as staving off failure, putting off dying. We have lost all confidence in the human body.

We are at our human finest, dancing with our minds, when there are more choices than two. Sometimes there are ten, even twenty different ways to go, all but one bound to be wrong, and the richness of the selection in such situations can lift us onto totally new ground.

The body of science is not, as it is sometimes thought, a huge coherent mass of facts, neatly arranged in sequence, each one attached to the next by a logical string. In truth, whenever we discover a new fact it involves the elimination of old ones. We are always, as it turns out, fundamentally in error.

It is in our genes to understand the universe if we can, to keep trying even if we cannot, and to be enchanted by the act of learning all the way.

I cannot think of a single field in biology or medicine in which we can claim genuine understanding, and it seems to me the more we learn about living creatures, especially ourselves, the stranger life becomes.

As evolutionary time is measured, we have only just turned up and have hardly had time to catch breath, still marveling at our thumbs, still learning to use the brand-new gift of language. Being so young, we can be excused all sorts of folly and can permit ourselves the hope that someday, as a species, we will begin to grow up.

We do not understand much of anything, from... the "big bang" , all the way down to the particles in the atoms of a bacterial cell. We have a wilderness of mystery to make our way through in the centuries ahead.

Good science is done by being curious in general, by asking questions all around, by acknowledging the likelihood of being wrong and taking this in good humor for granted, by having a deep fondness for nature, and by being made jumpy and nervous by ignorance.

The greatest of all the accomplishments of 20th century science has been the discovery of human ignorance