A Chinese Biographical Dictionary/Chêng Chan-yin
263 Chêng Chan-yin 鄭詹尹. The Chief Augur to whom Ch'ü Yüan applied for advice as to whether he should give up official life. But the Chief Augur gathered up his divining apparatus and saluted him, saying, "A foot is oft-times too short; an inch, too long. The implements of my art are not adequate to your requirements. Think for yourself and translate your thoughts into action. The divining-rod and the tortoise-shell would avail you naught."