Cao Cao lost no time in calling a council. Then High Minister Liu Ye said, “The loss of Hanzhong would shake the whole country. You, O Prince, must not shrink from toil and hardship, but must yourself go to lead the army.”
“This state of things comes of my not heeding your words before, gentle Sir,” said Cao Cao, then repentant.
However, Cao Cao hastily prepared and issued an edict to raise an army of four hundred thousand troops which he would lead.
The army was ready in the seventh month, the early autumn, in the twenty-third year (AD 218), and marched in three divisions. The leading division was under Xiahou Dun, Cao Cao commanded the center, and Cao Xiu was the rear guard.
Cao Cao rode a white horse, beautifully caparisoned. His guards were clad in embroidered silk. They carried the huge red parasol woven of silk and gold threads. Beside him in two lines were the symbols of kingly dignity, the golden melons, silver axes, stirrups, clubs, spears, and lances; banderoles embroidered with the sun and moon, dragon and phoenix, all were borne aloft. His escort of twenty-five thousand stout warriors led by bold officers, marched in five columns of five thousand each, under banners of the five colors, blue, yellow, red, white, and black. The five companies made a brave show as they marched, each column under its own flag with soldiers in armor and horses in caparisons all of one color and all glittering in the sun.
As they debouched through Tong Pass, Cao Cao noticed in the distance a thick wood, very luxuriant, and asked those near him what it was called.
“This place is the Indigo Field,” they replied. “And in that wood is the estate of the late Minister Cai Yong. His daughter, Cai Yan, and her present husband, Dong Si, live there.”
Now Cao Cao and Cai Yong had been excellent friends at one time. Cai Yong's daughter had been first married to Wei Zhongdao. Then she was abducted by the frontier tribes and taken away to the north, where she had borne two sons. She had composed a ballad called “Eighteen Stanzas for the Mongol Flageolet,” which was widespread to the empire. Cao Cao had been moved by pity for her sorrows and sent a messenger with a thousand ounces of gold to ransom her. The Prince of the frontier Xiongnu State, Ce Xian the Khan, overawed by Cao Cao's strength, had restored her to Cai Yong.
Ordering his escort to march on, Cao Cao went up to the gate with only a few attendants, dismounted and inquired after the lady of the house. At this time Dong Si was absent at his post, and the lady was alone. As soon as she heard who her visitor was, she hastened to welcome him and led him into the reception room. When Cao Cao was seated and she had performed the proper salutations, she stood respectfully at his side. Glancing round the room, Cao Cao saw a rubbing of a tablet hanging on the wall. So he got up to read it, and asked his hostess about it.
“It is a tablet of Cao E, or the fair Lady Cao. In the time of the Emperor He (AD 100), in the Xiongnu State there was a certain magician named Cao Xu, who could dance and sing like the very Spirit of Music. On the fifth of the fifth month he was out in a boat, and being intoxicated, fell overboard and was drowned. He had a daughter, Cao E, then fourteen years of age. She was greatly distressed and sought the body of her father for seven days and nights, weeping all the while. Then she threw herself into the waves, and five days later she floated to the surface with her father's body in her arms. The villagers buried them on the bank, and the magistrate reported the occurrence to the Emperor as a worthy instance of daughterly affection and remarkable piety.
“A later magistrate had the story inscribed by Handan Chun in memory of the event. At that time Handan Chun was only thirteen, but the composition of the inscription was so perfect that neither jot nor tittle could be added, and yet he had written it impromptu without revision. The stone was set up beside the grave, and both inscription and story were the admiration of all the people of that day. My father went to see it. It was evening, but in the obscurity he felt out the inscription with his fingers. He got hold of a pencil and wrote eight large characters on the reverse of the stone and, later, some person recutting the stone engraved these eight words as well.”
Cao Cao then read the eight words; they formed an enigma. Literally they read, “yellow silk, young wife, a daughter's child, pestle and mortar.”
“Can you explain?” asked Cao Cao of his hostess.
“No; although it is a writing of my father's, thy handmaid cannot interpret it,” she replied.
Turning to the strategists of his staff, Cao Cao said, “Can any one of you explain it?” But no one made any reply. Suddenly, they heard one voice, “I have grasped the meaning of it.”
The man who said he had fathomed the meaning was First Secretary Yang Xiu.
“Do not tell me yet; let me think it out,” said Cao Cao.
