Duke Mu of Qin ignored a ninety-year-old's warning and lost his whole army at Xiao

In 627 BCE a Qin officer garrisoned in Zheng sent word to Duke Mu of Qin that he held the keys to Zheng's north gate, and that a surprise army could take the state. Duke Mu resolved to send a force on a long march to ambush Zheng. His old minister Jian Shu objected: to weary the army in a distant raid was unheard of; the army's strength would be spent and the distant ruler would be prepared; whatever the army did, Zheng was sure to learn it; and a march of a thousand li could not stay secret, for who would not know of it?

Duke Mu refused to listen. When Jian Shu pressed him, the Duke sent a messenger to insult him: 'What do you know? Had you died at middle age, the trees on your grave would be two hands wide by now.' Jian Shu wept as the army left the eastern gate: 'Meng Ming — I see the army go out, but I will not see it come back.' He wept for his own son, who marched with the force, and named the place of death: the men of Jin would surely meet the army at Xiao, and between the two ridges there, he said, he would gather his son's bones.

The surprise did not survive the march. At the border town of Hua a Zheng merchant, Xian Gao, met the army on his way to trade. He presented twelve oxen and bundles of leather as a gift and announced that his lord, hearing of the army's approach, stood ready to receive it — and at the same time sent a rider to warn Zheng. The Qin generals concluded that surprise was lost and Zheng was prepared, and turned back without attacking.

On the return march, in the fourth month, the army of Jin and the Jiang Rong fell on the Qin force in the passes of Xiao and destroyed it. The three Qin generals — Meng Ming Shi, Xi Qi Shu and Bai Yi Bing — were captured and carried back to Jin. Jian Shu's prediction came exact: the army went out and did not come back, and the ridge he named was where it died.