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.

You will never stub your toe standing still. The faster you go, the more chance there is of stubbing your toe, but the more chance you have of getting somewhere.

An inventor fails 999 times, and if he succeeds once, he's in. He treats his failures simply as practice shots.

One of the things we have to be thankful for is that we don't get as much government as we pay for.

Failures, repeated failures, are sign-posts on the road to achievement. The only time you don't want to fail is the last time you try something (and it works).

The only time you mustn't fail is the last time you try.

I expect to spend the rest of my life in the future, so I want to be reasonably sure of what kind of future it's going to be. That is my reason for planning.