Two things are infinite: the universe and human stupidity; and I'm not sure about the universe.
There are only two ways to live your life. One is as though nothing is a miracle. The other is as though everything is a miracle.
I am enough of an artist to draw freely upon my imagination. Imagination is more important than knowledge. Knowledge is limited. Imagination encircles the world.
If you can't explain it to a six year old, you don't understand it yourself.
Logic will get you from A to Z; imagination will get you everywhere.