It means: to study extensively, to inquire about knowledge in detail, to think carefully, to distinguish clearly, and to practice it practically.
Source of the work: "The Doctrine of the Mean·Chapter 20"
Original text:
Learn eruditely, examine it, think carefully, discern it clearly, and practice it sincerely. There is no learning, and learning cannot be done, and there is no way; there is no questioning, and asking is not knowing, and there is no way; there is no thinking, and thinking is not possible, and there is no way; there is no discerning, If there is no clear distinction, there is no way to do it; if there is no way to practice it, if it is not done carefully, then there is no way to do it. If a person can do it once, he can do it by a hundred; if a person can do it by ten, he can do it by a thousand. If you can do this, you will be wise even if you are stupid, and you will be strong even if you are soft.
Translation:
Study extensively, inquire about knowledge in detail, think carefully, discern clearly, and practice it practically. If you don’t learn, it’s enough. If you don’t learn, you can’t stop until you understand.
If you don’t ask for advice, it’s enough. Since you’ve asked for advice, you can’t stop until you understand it thoroughly. If you don’t think, it’s enough. Since you think, it’s enough. If you don't want to come up with some truth, you can't stop; if you don't discern it, you can't stop it until you understand it;
If you don't do it, you can't do it. Consummation can never end. If others learn it once, I will learn it a hundred times; if others learn it ten times, I will learn it a thousand times.
If this method can be implemented, even stupid people will definitely become smarter, and even weak people will definitely become strong.
Extended information:
Analysis:
“Learn erudition, examine it, think carefully, discern clearly, and practice it diligently” from "The Doctrine of the Mean·Twenty chapter".
This is talking about several levels of learning, or several progressive stages. "Erudition" means that in order to learn, you must first hunt extensively and cultivate abundant and vigorous curiosity.
When curiosity is lost, the desire to learn dies, and erudition becomes impossible. "Bo" also means broad-minded and tolerant. Only by being broad-minded and tolerant can we be inclusive, enable our school to have a global perspective and an open mind, and truly achieve "the sea is open to all rivers, and tolerance is great", and then "love everyone and be kind".
Therefore, erudition can become the first stage of learning. Beyond this stage, learning is like a tree without roots and water without a source. "Interrogation" is the second stage. If you don't understand something, you need to get to the bottom of it and doubt what you have learned.
After asking, you must carefully examine and analyze it through your own ideological activities, otherwise what you have learned cannot be used by yourself, which is "thinking carefully".
"Clear argument" is the fourth stage. Learning becomes clearer with more debate. Without debate, the so-called "eruditeness" will be a mixed bag of good and bad, and it will be difficult to distinguish the true from the false, and the good from the bad will not be distinguished.
"Practice with sincerity" is the final stage of learning, that is, since you have learned something, you must work hard to practice what you have learned, so that what you have learned can finally be implemented, and achieve "the unity of knowledge and action."
"Du" means loyalty, down-to-earth, single-mindedness and perseverance. Only those with clear goals and firm will can truly "practice diligently".