Man is not made for space. But with the help of biologists and medical doctors, he can be prepared and accommodated.

My experiences with science led me to God. They challenge science to prove the existence of God. But must we really light a candle to see the sun?

I have learned to use the word 'impossible' with the greatest caution.

Science does not have a moral dimension. It is like a knife. If you give it to a surgeon or a murderer, each will use it differently.

Basic research is what I am doing when I don't know what I am doing.

It was very successful, but it fell on the wrong planet.

The rocket worked perfectly, except for landing on the wrong planet.

It takes sixty-five thousand errors before you are qualified to make a rocket.

The best computer is a man, and it’s the only one that can be mass-produced by unskilled labor.

Don't tell me that man doesn't belong out there. Man belongs wherever he wants to go - and he'll do plenty well when he gets there.

I believe in an immortal soul. Science has proved that nothing disintegrates into nothingness. Life and soul, therefore, cannot disintegrate into nothingness, and so are immortal.

Every new morning, I write a grateful gratitude for the new grace.

Nowadays, everybody wanna be weird. We know how to manifest being weird.

Could I tell them I was sorry their loved one was dead, when he’d tried to kill me? There was no rule of etiquette for this; even my grandmother would have been stymied.

Just because you cannot fight every evil does not mean you should fight no evils.

a lady could do, so I was told, just about nothing that she might want to do except attend all parties.

Well-bred instinct meets reason halfway

Artistry is to a large degree simplicity.

We must not seek happiness in peace, but in conflict.

Many great ideas need refreshment and deeper analysis. "Freedom," for example, is a great idea but it has become a cliché.

Success is brought by continued labor and continued watchfulness. We must struggle on, not for one moment hesitate, nor take one backward step.