Favorite Quotations?

Do you have a favorite quotation?  I’m a C. S. Lewis fan (or nut depending on your point-of-view) so I have a lot of Lewis favorite quotes.  Here are a couple of them:

“I believe in Christianity as I believe that the sun has risen: not only because I see it, but because by it I see everything else.” ~ C. S. Lewis

“Literature adds to reality, it does not simply describe it.  It enriches the necessary competencies that daily life requires and provides; and in this respect, it irrigates the deserts that our lives have already become.” ~ C. S. Lewis

What are your favorite quotes?  Please share them here, knowing (of course) that I might borrow them sometime in the future.  =)

Optimisitically yours,