The purpose of reading for learning is to entertain, to decorate and to increase knowledge. The main use of learning in entertainment is seclusion and keeping quiet; The use of knowledge in decoration is rhetoric; The purpose of learning is to judge and handle affairs. Because experienced people are good at execution, they may be able to judge individual things one by one; But the best overall evaluation and planning and arrangement of affairs come from learned people. It is lazy to spend too much time on study; It is false to regard learning too much as decoration; It is the quirk of scholars to judge things completely according to the laws of learning. Learning to exercise nature is itself the tempering of experience; The talents of beggars are like wild flowers and weeds, which need pruning of knowledge; And learning itself, if not limited by experience, is too general. Cunning people despise learning, fools envy learning, and wise people use learning; Because learning itself does not teach people how to use them; This way of application is a kind of intelligence beyond learning, which can only be obtained through observation and experience. Don't study for refutation, and don't blindly follow for faith; Don't talk; We should aim at being able to weigh and check things.

Some books can be tasted, some books can be swallowed, and a few books should be chewed and digested; In other words, it is enough to read only part of some books, and some books can be read completely, but you don't have to read them too carefully; There are several books that should be read completely, diligently and attentively. Some books can also be read by delegates and summarized by others for me; But this method is only applicable to the second discussion and the second publication; Otherwise, the book to be recorded is as tasteless as distilled water. Reading makes a full man, conversation makes a quick man, and writing and taking notes make an exact man. Therefore, if a person writes very little, then his memory must be good; If he seldom talks to people, then he must be a witty person; And if he reads little, then he must have great cunning to be strong and ignorant. Historical lessons make people wise; Poetry makes people wise; Mathematics makes people fine; Natural history is profound; The study of ethics makes people solemn; Logic and rhetoric are eloquent. "Learning changes temperament". Not particularly, there is no mental defect that cannot be remedied through a lot of study: just like all kinds of physical patients have proper exercise to treat them. Playing football is good for stones and kidneys; Archery is good for the chest and lungs; Walking slowly is good for the stomach; Riding a horse is good for the brain; And so on. At the same time, if a person's mind is not specialized, he'd better study mathematics; Because in mathematical reasoning, if his spirit is a little unprofessional, he will have to do it again. If his spirit is not good at distinguishing similarities and differences, then he'd better study the works of the scholastic school, because this scholastic school is a person who analyzes everything; If he is not good at pushing this and understanding that, he'd better study the lawyer's file. In this way, various mental defects can have a special remedy.