In the 11th century BCE, the 80-year-old Jiang Ziya, disgusted by King Zhou of Shang's tyranny, abandoned his post and fled into seclusion by the Wei River in Shaanxi.
Jiang Ziya, the legendary strategist, lived in seclusion under the rule of Ji Chang, the ambitious leader of the Zhou tribe who was desperate for talent. Eager to serve under Ji Chang but unwilling to approach him directly, Jiang Ziya devised a peculiar scheme to catch his attention.
He sat fishing by the Wei River every day. His fishing rod was short, the hook was straight with no bait, and it hung above the water. As he fished, he muttered to himself, "Fish in the river, if you don't want to live anymore, just jump onto my hook!"
A woodcutter saw Jiang Ziya fishing this way and found it very strange, so he said to him, "Fishing like this, when will you ever catch a fish?" "My goal is not about catching fish. I prefer to take the straight path and disdain to seek through crooked means. My true aim is to catch a king and a marquis!"
Soon, news of Jiang Ziya reached Ji Chang, who sent a soldier to summon him. Ignoring the soldier completely, Jiang Ziya kept fishing and said, "Fish! Fish! Fish! If the big fish won't bite, the little shrimp just fuss and fight!"
The soldier had no choice but to return and report to Ji Chang, who then sent an official to extend the invitation instead.
Jiang Ziya saw an official approaching but ignored him completely, saying while fishing, "Fish! Fish! Fish! Big fish won't take the bait, little fish, don't make a fuss!"
The official had no choice but to return and report to Ji Chang, who then realized that this old fisherman was a genius of unmatched brilliance. So Ji Chang fasted and purified himself in the palace for three days, then went in person with lavish gifts to recruit him. Seeing Ji Chang’s sincere heart, Jiang Ziya agreed to serve him.
Ji Chang held Jiang Ziya in high regard, appointing him as Grand Duke and his military advisor
Later, people used the idiom "The Duke of Zhou Fishes" to describe willingly falling into a trap.
Source: *The Plain Tale of King Wu's Conquest of Zhou*
Meaning of the Idiom: Later, the Chinese idiom "太公钓鱼" came to describe willingly falling into a trap.