When we think of the major threats to our national security, the first to come to mind are nuclear proliferation, rogue states and global terrorism. But another kind of threat lurks beyond our shores, one from nature, not humans – an avian flu pandemic.

In wildness is the preservation of the world.

To me a lush carpet of pine needles or spongy grass is more welcome than the most luxurious Persian rug.

Poets say science takes away from the beauty of the stars – mere globs of gas atoms. I, too, can see the stars on a desert night, and feel them. But do I see less or more?

All cartoon characters and fables must be exaggeration, caricatures. It is the very nature of fantasy and fable.

How strange that nature does not knock, and yet does not intrude!

When George W. Bush came into office, North Korea had maybe one nuclear weapon and verifiably wasn’t producing any more.

Philosophically considered, the universe is composed of Nature and the Soul. Strictly speaking, therefore, all that is separate from us, all which Philosophy distinguishes as the ‚Not Me,‘ that is, both nature and art, all other men and my own body, must be ranked under this name, ‚Nature.‘

What is a farm but a mute gospel?

Nature hath framed strange fellows in her time.

The sky is the part of creation in which nature has done for the sake of pleasing man.

No traveler, whether a tree lover or not, will ever forget his first walk in a sugar-pine forest. The majestic crowns approaching one another make a glorious canopy, through the feathery arches of which the sunbeams pour, silvering the needles and gilding the stately columns and the ground into a scene of enchantment.

No nation should stoke instability in its neighbor’s country.

Isn’t it enough to see that a garden is beautiful without having to believe that there are fairies at the bottom of it too?

To whom it may concern: It is springtime. It is late afternoon.

Long stormy spring-time, wet contentious April, winter chilling the lap of very May; but at length the season of summer does come.

For a successful technology, reality must take precedence over public relations, for Nature cannot be fooled.

Probably because I’m from a middle class family, I have that nature in me that I don’t get too excited with big things.

I was born poor and without religion, under a happy sky, feeling harmony, not hostility, in nature. I began not by feeling torn, but in plenitude.

The beginning of reform is not so much to equalize property as to train the noble sort of natures not to desire more, and to prevent the lower from getting more.

How inappropriate to call this planet Earth when it is quite clearly Ocean.

We cannot command Nature except by obeying her.

Nature gives you the face you have at twenty; it is up to you to merit the face you have at fifty.

Trees go wandering forth in all directions with every wind, going and coming like ourselves, traveling with us around the sun two million miles a day, and through space heaven knows how fast and far!

The sky is the daily bread of the eyes.

I love the natural world – it comes from my culture, which grew out of a people enslaved.

China is certainly an important player in the global economy, and a widespread AIDS epidemic would threaten that growth.

Nature and nature’s laws lay hid in the night. God said, Let Newton be! and all was light!

Do not be very upright in your dealings for you would see by going to the forest that straight trees are cut down while crooked ones are left standing.

Nature has always had more force than education.

The professed function of the nuclear weapons on each side is to prevent the other side from using their nuclear weapons. If that’s all it is, then we’ve gotta as: how many nuclear weapons do you need to do that?

One touch of nature makes the whole world kin.

The moral virtues, then, are produced in us neither by nature nor against nature. Nature, indeed, prepares in us the ground for their reception, but their complete formation is the product of habit.

Two things control men’s nature, instinct and experience.

Consistency is contrary to nature, contrary to life. The only completely consistent people are dead.

Nature shows that with the growth of intelligence comes increased capacity for pain, and it is only with the highest degree of intelligence that suffering reaches its supreme point.

A wounded deer leaps the highest.

I just think cities are unnatural, basically. I know there are people who live happily in them, and I have cities that I love, too. But it’s a disaster that we have moved so far from nature.

I value my garden more for being full of blackbirds than of cherries, and very frankly give them fruit for their songs.

To be admitted to Nature’s hearth costs nothing. None is excluded, but excludes himself. You have only to push aside the curtain.

Even though I write about the human race, the further away from them, the better I feel. Two miles is great; two thousand miles is beautiful.

We are all full of weakness and errors; let us mutually pardon each other our follies – it is the first law of nature.

Studies perfect nature and are perfected still by experience.

A wind has blown the rain away and blown the sky away and all the leaves away, and the trees stand. I think, I too, have known autumn too long.

What constitutes a real, live human being is more of a mystery than ever these days, and men each one of whom is a valuable, unique experiment on the part of nature are shot down wholesale.

Necessity is the mistress and guide of nature. Necessity is the theme and inventress of nature, her curb and her eternal law.

I am a leader by default, only because nature does not allow a vacuum.

In the world there is nothing more submissive and weak than water. Yet for attacking that which is hard and strong nothing can surpass it.

Walking is man’s best medicine.

First I shake the whole Apple tree, that the ripest might fall. Then I climb the tree and shake each limb, and then each branch and then each twig, and then I look under each leaf.

Only when you drink from the river of silence shall you indeed sing. And when you have reached the mountain top, then you shall begin to climb. And when the earth shall claim your limbs, then shall you truly dance.

We’ve climbed the mighty mountain. I see the valley below, and it’s a valley of peace.

The worst pandemic in modern history was the Spanish flu of 1918, which killed tens of millions of people. Today, with how interconnected the world is, it would spread faster.

Going to the woods is going home, for I suppose we came from the woods originally. But in some of nature’s forests, the adventurous traveler seems a feeble, unwelcome creature; wild beasts and the weather trying to kill him, the rank, tangled vegetation, armed with spears and stinging needles, barring his way and making life a hard struggle.

Custom is our nature. What are our natural principles but principles of custom?

Nature never breaks her own laws.

All the world lies warm in one heart, yet the Sierra seems to get more light than other mountains. The weather is mostly sunshine embellished with magnificent storms, and nearly everything shines from base to summit – the rocks, streams, lakes, glaciers, irised falls, and the forests of silver fir and silver pine.

Nature does not hurry, yet everything is accomplished.

Nature is full of genius, full of the divinity; so that not a snowflake escapes its fashioning hand.

We’re in greater danger today than we were the day after Pearl Harbor. Our military is absolutely incapable of defending this country.

Trying to understand the way nature works involves a most terrible test of human reasoning ability. It involves subtle trickery, beautiful tightropes of logic on which one has to walk in order not to make a mistake in predicting what will happen. The quantum mechanical and the relativity ideas are examples of this.