All one can really leave one's children is what's inside their heads. Education, in other words, and not earthly possessions, is the ultimate legacy, the only thing that cannot be taken away.

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

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

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

Development of the space station is as inevitable as the rising of the sun; man has already poked his nose into space and he is not likely to pull it back . . . . There can be no thought of finishing, for aiming at the stars-both literally and figuratively-is the work of generations, and no matter how much progress one makes, there is always the thrill of just beginning.

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

What we will have attained when Neil Armstrong steps down upon the moon is a completely new step in the evolution of man.