I’ve learned that people will forget what you said, people will forget what you did, but people will never forget how you made them feel.

The important thing is not to stop questioning.

“It’s your place in the world; it’s your life. Go on and do all you can with it, and make it the life you want to live.”

To invent, you need a good imagination and a pile of junk.

Imagination is everything. It is the preview of life's coming attractions.

I am only one, but still I am one. I cannot do everything, but still I can do something; and because I cannot do everything, I will not refuse to do something that I can do.

Every man contains within him all the possibilities of the universe.