Silence must be comprehended as not solely the absence of sound. It is the natural environment for serenity and contemplation. Life without silence is life without privacy. The difference between sanity and madness is the quality of our thoughts. Silence is on the side of sanity.

Wisdom consists of the anticipation of consequences.

The need is not to amputate the ego ... but to transcend it.

To be able to rise from the earth; to be able, from a station in outer space, to see the relationship of the planet earth to other planets; to be able to contemplate the billions of factors in precise and beautiful combination that make human existence possible; to be able to dwell on an encounter of the human brain and spirit with the universe

I have learned never to underestimate the capacity of the human mind and body to regenerate - even when prospects seem most wretched. The life force may be the least understood force on earth.

Do you prefer that you be right or happy?

We have everything we need, in fact, except the most important thing of all — time to think and the habit of thought.