During the Battle of Red Cliffs in the Three Kingdoms period, Zhuge Liang, Liu Bei's strategist, arrived in Eastern Wu and debated the assembled scholars, ultimately persuading Sun Quan to join forces with Liu Bei against Cao Cao at Red Cliffs.
Zhou Yu, the commander under Sun Quan, was a man of both literary and military talent, but his heart was narrow. Seeing that Zhuge Liang's abilities surpassed his own, he schemed relentlessly for a chance to eliminate him.
During a military campaign, Zhou Yu deliberately claimed a shortage of arrows and ordered Zhuge Liang to produce 100,000 arrows within ten days. Aware of Zhou Yu's scheme, Zhuge Liang confidently replied, "I only need three days to complete the task; if I fail, I will accept military punishment."
Zhou Yu secretly rejoiced, certain that Zhuge Liang could never produce 100,000 arrows in just three days. Believing Zhuge Liang was walking into a death trap, Zhou Yu ordered the army's craftsmen to deliberately delay and withhold the materials he needed.
However, for the first two days, Zhuge Liang did not mention the arrow-making at all. Instead, he secretly approached the general Lu Su and borrowed twenty fast boats. Each boat was manned by thirty soldiers, with hundreds of straw dummies tied at the bow and stern, all covered with blue cloth.
On the third day before dawn, Zhuge Liang calculated that a thick fog was certain to roll in
The Cao army was thrown into panic, believing the Eastern Wu navy had launched a surprise attack
In less than an hour, the straw dummies were bristling with arrows. Zhuge Liang ordered his soldiers to shout, "Thank you, Prime Minister, for the arrows!" and returned fully loaded.
Zhuge Liang returned to the Eastern Wu camp and ordered his soldiers to collect the arrows, reporting that they had gathered over 100,000 arrows.
Zhou Yu was astonished, not knowing what had happened. Lu Su told him how Zhuge Liang had borrowed the arrows, and he couldn't help but sigh, "Zhuge Liang's divine foresight and brilliant calculations—I am no match for him!" Later, the idiom "divine foresight and brilliant calculations" came to be used to describe exceptional strategic planning.
*Romance of the Three Kingdoms*
Meaning of the Idiom: Later, the Chinese idiom "神机妙算" came to describe exceptional strategic planning.