The countries outside the Non-Proliferation Treaty also are bound by that obligation [ Article Six of the treaty] according to, at least it's a strong implication of, a 1996 opinion of the International Court of Justice.

The secret of happiness is something to do.

[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.

There is a condition or circumstance that has a greater bearing upon the happiness of life than any other. What is it? Something to do; some congenial work. Take away the occupation of all people and what a wretched world it would be.

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

The life of nature we must meet halfway; it is shy, withdrawn, and blends itself with a vast neutral background.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.

The lure of the distant and the difficult is deceptive. The great opportunity is where you are.