The mind, once stretched by a new idea, never returns to its original dimensions.
A man may die, nations may rise and fall, but an idea lives on.
Ideas are like rabbits. You get a couple and learn how to handle them, and pretty soon you have a dozen.
A person with a new idea is a crank until the idea succeeds.
Don't worry about people stealing your ideas.
Great minds discuss ideas; average minds discuss events; small minds discuss people.
Nothing is more dangerous than an idea when it is the only one you have.
An idea that is not dangerous is unworthy of being called an idea at all.
Everyone who's ever taken a shower has an idea. It's the person who gets out of the shower, dries off and does something about it who makes a difference.
Don't worry about people stealing your ideas. If your ideas are any good, you'll have to ram them down people's throats.
A mediocre idea that generates enthusiasm will go further than a great idea that inspires no one.
Ideas won't keep. Something must be done about them.
I can't understand why people are frightened of new ideas. I'm frightened of the old ones.
If at first the idea is not absurd, then there is no hope for it.
The ideas I stand for are not mine. I borrowed them from Socrates. I swiped them from Chesterfield. I stole them from Jesus. And I put them in a book. If you don't like their rules, whose would you use?
I had a monumental idea this morning, but I didn't like it.
An idea isn't responsible for the people who believe in it.
Human history is, in essence, a history of ideas.
Take up one idea. Make that one idea your life - think of it, dream of it, live on that idea. Let the brain, muscles, nerves, every part of your body, be full of that idea, and just leave every other idea alone. This is the way to success.
Any man who afflicts the human race with ideas must be prepared to see them misunderstood.
or simply: