The essence of man is imperfection.

The doctor knows that it is the prescription slip itself, even more than what is written on it, that is often the vital ingredient for enabling a patient to get rid of whatever is ailing him.

The individual is capable of both great compassion and great indifference. He has it within his means to nourish the former and outgrow the latter.

The only security for the American people today, or for any people, is to be found through the control of force rather than the use of force.

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

The real wealth, not only of America, but of the world, is in the resources of the ground we stand on, and in the resources of the humankind.

If something comes to life in others because of you, then you have made an approach to immortality.