Great steps in human progress are made by things that don't work the way philosophy thought they should. If things always worked the way they should, you could write the history of the world from now on. But they don't, and it is those deviations from the normal that make human progress.

Don't be afraid to stumble. Any inventor will tell you that you don't follow a plan far before you strike a snag. If, out of 100 ideas you get one that works, it's enough.

I don't want men of experience working for me. The experienced man is always telling me why something can't be done. The fellow who has not had any experience is so dumb he doesn't know a thing can't be done - and he goes ahead and does it.

It doesn't matter if you try and try and try again, and fail. It does matter if you try and fail, and fail to try again.

People are very open-minded about new things - as long as they're exactly like the old ones.

A problem well stated is a problem half-solved.

Keep on going and the chances are you will stumble on something, perhaps when you are least expecting it. I have never heard of anyone stumbling on something sitting down.