We owe our lives to the sun... How is it, then, that we feel no gratitude?

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.

The capacity to blunder slightly is the real marvel of DNA. Without this special attribute, we would still be anaerobic bacteria and there would be no music.

Statistically, the probability of any one of us being here is so small that you'd think the mere fact of existing would keep us all in a contented dazzlement of surprise.

In real life, every field of science is incomplete, and most of them - whatever the record of accomplishment during the last 200 years - are still in their very earliest stages.

The greatest single achievement of nature to date was surely the invention of the molecule DNA.

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 would send the complete works of Johann Sebastian Bach into outer space on the Voyager spacecraft. But that would be boasting.

Animals have genes for altruism, and those genes have been selected in the evolution of many creatures because of the advantage they confer for the continuing survival of the species.

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

At this early stage in our evolution, now through our infancy and into our childhood and then, with luck, our growing up, what our species needs most of all, right now, is simply a future.

These things sneak up on him for no reason, these flashes of irrational happiness. It's probably a vitamin deficiency.

Do young people have the moral stamina to carry through in case of economic depression? . . . The real tests of the [younger] generations have not yet come, but they are on their way!

Don't be telling me--can't be done. That's some god damney white talk, that's what that is.

Despair is a narcotic. It lulls the mind into indifference.

Conscience is God's presence in humans.

I'm very cagey about making friends, and I rarely do.

Home is the place that goes where you go, yet it welcomes you upon your return. Like a dog overjoyed at the door. We've missed you is what you hear, no matter how long you've been gone.

There is no recollection which time does not put an end to, and no pain which death does not remove.

The ever-present phenomenon ceases to exist for our senses. It was a city dweller, or a prisoner, or a blind man suddenly given his sight, who first noted natural beauty.

Each victory gained over oneself means new strength to gain more victories.