At the end of 1199, the fifth year of Emperor Ningzong's reign in the Song Dynasty, Lu You wrote a poem "Reading on a Winter Night to Show Ziyu". The meaning of this poem is that the ancients spared no effort in learning. A lifelong struggle often starts when you are young and only succeeds when you are old. The knowledge obtained from books is ultimately shallow and fails to understand the true meaning of knowledge. To truly understand the profound principles in the book, one must practice it personally. This is a very famous poem. In this poem, the poet emphasizes on the one hand the need to persevere in learning and to work hard early, so as to avoid "young people not working hard, old people being sad", and accomplishing nothing in the future and regretting it. On the other hand, special emphasis is placed on "where" the effort in learning should be put. This is also the secret of learning, that is, one cannot be satisfied with literal understanding, but must practice it and deepen understanding in practice. Only in this way can you turn the knowledge in books into your own practical skills. Regarding the relationship between books and practice, the poet emphasized the importance of practice, which is in line with the viewpoint of materialist epistemology. The author's opinion is not only a very valuable experience for people to learn and seek knowledge in feudal society, but also very enlightening for people today. It is a very valuable insight.