Reading is a pleasure of the mind, which means that it is a little like a sport: your eagerness and knowledge and quickness count for something. The fun of reading is not that something is told to you, but that you stretch your mind. Your own imagination works along with the authors, or even goes beyond his, yields the same or different conclusions, and your ideas develop as you understand his.
Bennett CerfThere once was a student named Bessor Whose knowledge grew lessor and lessor. It at last grew so small He knew nothing at all, And today he's a college professor!
Bennett Cerf