During the late Spring and Autumn period, the southern state of Chu grew increasingly powerful, steadily annexing smaller neighboring states. In 585 BCE, Chu launched a military campaign against the state of Zheng. Unable to withstand Chu's formidable assault, Zheng appealed to the state of Jin for help.
When the State of Zheng, an ally of Jin, came under attack by Chu, Duke Jing of Jin could not stand idly by. He immediately dispatched his general Luan Shu with an army to rescue Zheng. As the Jin forces entered Zheng's territory, they soon encountered the Chu army. Seeing the overwhelming momentum of the Chu troops, the Jin army chose to withdraw and return home.
Luan Shu, furious that Cai had allied with Chu, led his army to attack. The ruler of Cai panicked and urgently sent word to Chu for reinforcements.
The state of Chu had no desire to engage the Jin army in battle. However, since the state of Cai was under its protection, Chu could not stand idly by. So it immediately dispatched Prince Shen and Prince Cheng to lead troops from the Shen and Xi counties to the rescue.
Luan Shu, furious upon hearing that the Chu army was coming to rescue the State of Cai, prepared to send two generals, Zhao Tong and another, to intercept the Chu forces. His subordinates, Han Xianzi and Fan Wenzi, advised against it, saying:
"The Chu army has turned back and their morale is high; they will certainly be difficult to deal with. Moreover, even if we win, we would only defeat the troops of two Chu counties, which is not worthy of glory. But if we lose, it would be a great disgrace—people would say that our Jin army couldn't even defeat two counties' worth of Chu troops. So it is better to withdraw and return home."
Luan Shu, finding their words reasonable, prepared to withdraw his troops and return home. Generals like Zhao Tong strongly disagreed and said to Luan Shu:
"Commander, with so many generals under your command, only three advocate withdrawing troops. Clearly, the majority favors fighting, and the majority is usually right. Why do you insist on listening to just those three?"
Luan Shu shook his head and replied, "You are mistaken. The correctness of an opinion does not lie in how many people support or oppose it. A majority view is not necessarily right, but a truly correct opinion will always represent the majority. Han Xianzi and the other two are all worthy ministers of Jin. Their view may seem to be in the minority, but in truth it represents the majority. Say no more—I have decided to adopt their advice."
Thereupon, Luan Shu ordered the army to withdraw and return to their home state.
Two years later, Luan Shu was again ordered to attack the states of Cai and Shen. With Han Xianzi and two others devising strategies for him, they achieved a swift and easy victory.
Because Luan Shu wisely heeded his subordinates' advice, people praised him, saying:
"Luan Shu truly follows good advice as naturally as water flows—what a fine example!" Later, the idiom "Following Good Advice Like a Flowing Stream" came to describe someone who humbly accepts correct opinions from others.
Source: *Zuo Zhuan*, Chapter "Duke Cheng's Eighth Year"
Meaning of the Idiom: Later, the Chinese idiom "从善如流" came to describe how someone humbly accepts correct opinions from others.