I was gratified to be able to answer promptly. I said, "I don't know."
Mark Twain (1835-1910) 

If a little knowledge is dangerous, where is the man who has so much as to be out of danger?
Thomas Henry Huxley 

If the human mind was simple enough to understand, we'd be too simple to understand it.
Emerson Pugh 

If written directions alone would suffice, libraries wouldn't need to have the rest of the universities attached.
Judith Martin  , "Miss Manners" columnist and author

Ignorance of one's misfortunes is clear gain.
Euripides 

Imagination is more important than knowledge.
Albert Einstein (1879-1955) 

In the republic of mediocrity genius is dangerous.
Robert G. Ingersoll 

Intelligence, in diapers, is invisible. And when it matures, out the window it flies. We have to pounce on it earlier.
Stanislaw J. Lec 

It has yet to be proven that intelligence has any survival value.
Arthur C. Clarke 

It is by the goodness of God that in our country we have those three unspeakably precious things: freedom of speech, freedom of conscience, and the prudence never to practice either of them.
Mark Twain (1835-1910)  , 1897