Source Zhu Zhuzi School Volume 14.
The clearer the understanding (of things and laws), the more solid the practice (under the guidance of understanding) and the richer the results; The more solid the practice, the richer the results and the clearer the understanding.
This sentence reveals the relationship between cognition and practice. Cognition and practice are interdependent and mutually reinforcing aspects. Cognition is the premise and guide of practice, and practice will further promote the in-depth development of cognition. Only by combining the two aspects can our understanding be closer to the truth and progress be faster. Of course, this is only part of practice-cognition-practice. Zhu still has considerable limitations in epistemology.