Literary Characters: The boy who will not grow up?

Questions

"The man who reads nothing at all is better educated than the man who reads nothing but ---------------."- Thomas Jefferson?

"If you tell the truth you don't have to ------------- anything."- Mark Twain?

"Look for the light behind every ---------."- Robert Schuler?

"The minute you start --------- about what you are going to do if you lose, you have lost."-George Schultz?

"The more I ----------, the more I realize I don't know."- Albert Einstein?