We delight in the beauty of the butterfly, but rarely admit the changes it has gone through to achieve that beauty.

You are never too old to become younger!

I confess that in 1901 I said to my brother Orville that man would not fly for fifty years.

Truth can be stated in a thousand different ways, yet each one can be true.

Always do what is right. It will gratify half of mankind and astound the other.

The limits of the possible can only be defined by going beyond them into the impossible.

People die from typewriters falling on their heads.

Work gives you meaning and purpose and life is empty without it.

The desire to reach for the stars is ambitious. The desire to reach hearts is wise.

One man with courage is a majority.

You must never be fearful about what you are doing when it is right.

People throw stones at you and you convert them into milestones.

Nothing great was ever achieved without enthusiasm.

Self-confidence is the first requisite to great undertakings.

Do not be afraid. Do not be satisfied with mediocrity. Put out into the deep and let down your nets for a catch.

One person with a belief is equal to a force of ninety-nine who have only interests.

The crisis of today is the joke of tomorrow.

If you think in terms of a year, plant a seed; if in terms of ten years, plant trees; if in terms of 100 years, teach the people.

All wealth is the product of labor.

Freedom from the desire for an answer is essential to the understanding of a problem.

Know thyself.