The floating vapour is just as true an illustration of the law of gravity as the falling avalanche.

The deeper our insight into the methods of nature . . . the more incredible the popular Christianity seems to us.

If I were to name the three most precious resources of life, I should say books, friends, and nature.

We have produced some good walkers and saunterers, and some noted climbers; but as a staple recreation, as a daily practice, the mass of the people dislike and despise walking.

Maybe that will happen with other countries as well. And so, that's why one of the things that groups like mine that work for the elimination of nuclear weapons and work for their marginalization in the meantime, we say you have to diminish the political value that's attached to nuclear weapons in order to give them less (kind of) desirability in the eyes of governments that do not now have them, and thus to help stop their spread.

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.

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.