I have discovered the secret of happiness - it is work, either with the hands or the head. The moment I have something to do, the draughts are open and my chimney draws, and I am happy.

[Nuclear weapons] now I think I mentioned around 27,000 and during the Cold War the total global arsenal was on the order of 70,000.

The life of nature we must meet halfway; it is shy, withdrawn, and blends itself with a vast neutral background. We must be initiated; it is an order the secrets of which are well guarded.

Nature will not be conquered, but gives herself freely to her true lover - to him who revels with her, bathes in her seas, sails her rivers, camps in her woods, and with no mercenary ends, accepts all.

The place to observe nature is where you are.

Some men are like nails, very easily drawn; others however are more like rivets never drawn at all.

I am in love with this world. It has been my home. It has been my point of outlook into the universe. I have never bruised myself against it nor tried to use it ignobly.