The wilderness and the idea of wilderness is one of the permanent homes of the human spirit.

Not to have known - as most men have not - either the mountain or the desert is not to have known one's self. Not to have known one's self is to have known no one.

Being the inventor of sex would seem to be a sufficient distinction for a creature just barely large enough to be seen by the naked eye.

It is not ignorance but knowledge which is the mother of wonder.

Love is ...not a fact in nature of which we become aware, but rather a creation of the human imagination.

Though we face the facts of sex we are more reluctant than ever to face the fact of death or the crueler facts of life, either biological or social.

Technology made large populations possible; large populations now make technology indispensable.