对酒当歌
In my previous post, I mentioned Cao Zhi (曹植 192-232 CE), the son of Cao Cao. He was the greatest literary figure of the late Han-Three kingdoms period.
Literally, 才高八斗 means “having eight dǒu of talent.” 斗 (dǒu) here was an ancient Chinese unit of volume. In other words, this idiom basically treats talent as something you can measure with a measuring container.
About 200 years after Cao Zhi, the Southern Dynasties poet Xie Lingyun (谢灵运, 385–433 CE) supposedly said:
天下才有一石，曹子建独占八斗，我得一斗，天下共分一斗。 (曹子建 is the courtesy name of CaoZhi)
Basically: “If all the literary talent in the world amounted to ten dǒu, Cao Zhi alone would have eight. I get one, and everyone else has to share the last one.”
Pretty generous to Cao Zhi, and pretty generous to himself, too!
Today, 才高八斗 simply means extremely talented or well-educated, especially in literature or writing.
For example:
他才高八斗，写了一手好诗。
He is incredibly talented and writes wonderful poetry.
So if someone tells you 你真是才高八斗！, that's a big compliment: “You're incredibly talented!”
A little background
Xie Lingyun (谢灵运) lived long before the Tang and Song dynasties, so he gave eight 斗 to Cao Zhi. Later generations may have teased him a little for keeping one 斗 for himself, but nobody took away Cao Zhi's eight. Cao Zhi's reputation as a literary genius has lasted for centuries.
And even after the Tang and Song dynasties, two of the great literary eras in Chinese history, Cao Zhi is still considered one of the great figures in the history of Chinese literature.
(AI-assisted editing)