Han Kangbo, an authority on Yijing Studies and an expert in Mysterious Debate, held a Jade Ruyi in his left hand and tapped it against his right palm, rather like a monk striking a wooden fish. He posed a challenge: "As for the functions of the Book of Changes, what constitutes their substance?"
Chen Caozhi answered, "Substance and function are like a lamp and its light: with a lamp, there is light; without a lamp, darkness. Or like a blade and its sharpness: with a blade, there is sharpness; without a blade, none."
Han Kangbo asked, "Neither the Six Classics, the Analects, nor Mencius ever mentioned the terms 'substance' and 'function.' Why is that?"
Chen Caozhi said, "Everything the Master said possessed both substance and function. His arguments were straightforward and lucid. In analyzing principles, the subtlety lies in grasping them in the heart. Why must everything have been said by the sages before us?"
Sima Yu, Xie Wan, Xi Chao, Zhu Fatai, Zhu Daoqian, and the others seated there all nodded in approval. The Wei-Jin vogue for metaphysical discourse prized breaking out of the molds of one's predecessors above all; rigid pedants commanded little respect.
Slightly embarrassed, Han Kangbo immediately turned to his greatest strength, the study of Yi Images. "The Commentary on the Images says, 'Heaven moves with vigor.' Images may be actual or figurative. How does one distinguish between them?"
Chen Caozhi said, "What the Book of Changes calls actual and figurative images is this: water upon the earth, or wood growing up from within the earth-these are no empty statements, and so they are called actual images. Figurative images include heaven within a mountain or wind emerging from fire. Such images do not exist in reality; they are borrowed to convey meaning, and are therefore called