“The person who says he knows what he thinks but cannot express it usually does not know what he thinks.”

“If you ask a living teacher a question, he will probably answer you. If you are puzzled by what he says, you can save yourself the trouble of thinking by asking him what he means. If, however, you ask a book a question, you must answer it yourself. In this respect a book is like nature or the world. When you question it, it answers you only to the extent that you do the work of thinking an analysis yourself.”

“A good book deserves an active reading. The activity of reading does not stop with the work of understanding what a book says. It must be completed by the work of criticism, the work of judging. The undemanding reader fails to satisfy this requirement, probably even more than he fails to analyze and interpret. He not only makes no effort to understand; he also dismisses a book simply by putting it aside and forgetting it. Worse than faintly praising it, he damns it by giving it no critical consideration whatever.”

“The ability to retain a child's view of the world with at the same time a mature understanding of what it means to retain it, is extremely rare - and a person who has these qualities is likely to be able to contribute something really important to our thinking.”

“There are genuine mysteries in the world that mark the limits of human knowing and thinking. Wisdom is fortified, not destroyed, by understanding its limitations. Ignorance does not make a fool as surely as self-deception.”

“If an author does not give reasons for his propositions, they can only be treated as expressions of personal opinion on his part.”

“Reading a book should be a conversation between you and the author. Presumably he knows more about the subject than you do; if not, you probably should not be bothering with his book. But understanding is a two-way operation; the learner has to question himself and question the teacher, once he understands what the teacher is saying. Marking a book is literally an expression of your differences or your agreements with the author. It is the highest respect you can pay him.”