People who say it cannot be done should not interrupt those who are doing it.

I was motivated by a desire to solve the world's most difficult problems.

In a world where you can be anything, be kind

The willow which bends to the tempest, often escapes better than the oak which resists it; and so in great calamities, it sometimes happens that light and frivolous spirits recover their elasticity and presence of mind sooner than those of a loftier character.

Patience, persistence, and perspiration make an unbeatable combination for success.

I never make the mistake of arguing with people for whose opinions I have no respect.

The best way to destroy an enemy is to make him a friend.