The most dangerous thing in the world is to try to leap a chasm in two jumps.

Ignorance more frequently begets confidence than does knowledge.  

I have come to believe that a great teacher is a great artist and that there are as few as there are any other great artists. Teaching might even be the greatest of the arts since the medium is the human mind and spirit.

To love truth for truth's sake is the principal part of human perfection in this world, and the seed-plot of all other virtues.

The most important thing is to stay alive.