"The way to know is to investigate things" comes from "Book of Rites and Great Learning": "The way to know is to investigate things, and then you will know." The meaning of "knowing things" is to investigate the truth of things and understand all things in the world. Wu Ge means that things are thoroughly investigated. The meaning of the original sentence is: Only by exploring the truth can we obtain the correct understanding, and only after understanding the truth can we realize the true city.

"The Great Learning" mentions "investigating things to achieve knowledge", but does not provide any explanation afterwards, and there are no pre-Qin ancient books that use the terms "investigating things" and "achieving knowledge", so "investigating things to achieve knowledge" "The true meaning of " has become a difficult mystery in Confucian thought. The sixth edition of "Modern Chinese Dictionary" published in 2012 explains "investigating things to achieve knowledge" as: "investigating the principles of things to obtain knowledge."

Extended information:

Studying things to achieve knowledge The root of the problem

The reason why "studying things to gain knowledge" is difficult to explain has caused controversy in Confucian circles for more than a thousand years. First of all, the difficulty is that "investigating things to gain knowledge" is the basic skill of the Eighth Objective of "The Great Learning", and it is also the basis of the practice of "sincerity and correct mind", which also involves the fundamental foundation of mind cultivation, and goes beyond the depth of thought of pre-Qin Confucianism. It is connected with the Taoist learning of pre-Qin Dynasty.

Secondly, after the rise of Confucianism in the Song Dynasty, Confucian scholars often denounced Taoism and Buddhism, making it increasingly difficult to understand their original meaning. In the history of Confucianism, Song Confucianism excluded Buddhism and Taoism. Cheng Yi created his own "Li" to replace "Dao" (Confucius discussed Dao but not Li), and Zhu Xi ignored the records in "Historical Records" and insisted on thinking that "Confucius visited The Lao Tzu whom Zhou paid homage to was not a Taoist Lao Tzu, but someone else."

Then, it is because it is difficult to properly interpret the meaning of the word "Studying things to achieve knowledge", so that the meaning of the word cannot be properly explained; this is also because there is a lack of documents related to the author's intention of "The Great Learning", which can be used to prove the meaning of "Studying things to achieve knowledge" correct meaning. As a result, various Confucian schools in the future often invented and forced explanations at will, thus causing eternal mysteries in Confucian thought to this day.

Reference source: Baidu Encyclopedia-Studying Things to Know