I've never heard of anyone stumbling on something sitting down.

All human development, no matter what form it takes, must be outside the rules; otherwise we would never have anything new.

Every father should remember one day his son will follow his example, not his advice.

The opportunities in this world are as great as we have the imagination to see them... but we never get that view from the bottom of the nest.

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).

It is not a disgrace to fail. Failing is one of the greatest arts in the world.

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.