More quotes by Mark Twain

"A clear conscience is the sure sign of a bad memory."
"If you pick up a starving dog and make him prosperous he will not bite you. This is the principal difference between a dog and man."
"A successful book is not made of what is in it, but what is left out of it."
"In a good bookroom you feel in some mysterious way that you are absorbing the wisdom contained in all the books through your skin, without even opening them."
"Everyone is a moon, and has a dark side which he never shows to anybody."