【成语来源】 

to win a war with words
纸上谈兵

In the Warring States Period (战国), the State of Zhao (赵国) had a famous general called Zhao She, whose son, Zhao Kuo, was very fond of reading books on military science and discussing strategy
战国时,赵国名将赵奢 (shē) 的儿子赵括,喜欢看兵书,并且喜爱讨论军事战术。

He could learn military texts by heart, and when discussing warfare he spoke so clearly and logically that it seemed that even his father was not his match.
他把兵书背得滚瓜烂熟,谈起打仗来头头是道,好像他的父亲都不是他的对手。

When the State of Qin attacked the State of Zhao, the ruler of Zhao ordered Zhao Kuo to lead 400,000 men to resist the attack.
当秦国攻进军攻击赵国的时候,赵王派赵括率领四十万大军去抵抗。

But since Zhao Kuo had no practical experience of battle, he was defeated and lost his life.
由于他只知道死抠书本而不会在实际中灵活运用,最后指挥失策,以致全军覆灭,他自己也中箭身亡。

Later people used this idiom to describe those who are good only at theorizing, and lack practical experience.
最后人们根据这一历史故事,把死抠书本,没有实际经验,只会夸夸其谈称为“纸上谈兵”。

【文化链接】

英语中“纸上谈兵”的表达方式相对比较直白,通常可以说“to win a war with words”,在经典影片《乱世佳人》中,战争爆发前夕,当南方贵族们在夸夸其谈讨论如何作战时,白瑞德就说道:

“I think it’s hard winning a war with words.”(“我认为纸上谈兵没什么作用。”)

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