When you get to a certain age, there is no coming back.

For a moment, nothing happened. Then, after a second or so, nothing continued to happen.

Learn to give, whether you have plenty or little, whether you are happy or in pain.

Design is not just what it looks like and feels like. Design is how it works.

Science is not only compatible with spirituality; it is a profound source of spirituality.

If the world was perfect, it wouldn't be.

The only thing worse than being blind is having sight but no vision.

You are like my little dog; when people see you, they know I am nearby.

The world is moving so fast these days that the man who says it can't be done is generally interrupted by someone doing it.

Remember upon the conduct of each depends the fate of all.

As I grow older, I pay less attention to what men say. I just watch what they do.

The American people should be made aware of the trend toward monopolization of the great public information vehicles and the concentration of more and more power over public opinion in fewer and fewer hands.

I speak for the trees, for the trees have no tongues.

I am one of those who think like Nobel, that humanity will draw more good than evil from new discoveries.

I want to sing like the birds sing, not worrying about who hears or what they think.

All men are liable to error; and most men are, in many points, by passion or interest, under temptation to it.

You always admire what you really don't understand.

Parents wonder why the streams are bitter, when they themselves have poisoned the fountain.

A mediocre idea that generates enthusiasm will go further than a great idea that inspires no one.

Advice to intellectuals: let no-one represent you.

Only two things are infinite, the universe and human stupidity, and I'm not sure about the former.