I'm sure my Chinese-speaking friends go through this all the time, but it's a first for me.
So here I am with my Power Japanese book,
Kanji Idioms, a run-down of four-kanji expressions such as, say, shoushin shoumei 正真正銘 (the real thing, the genuine article) or the famous kiyou binbou 器用貧乏 (inevitably-- 'jack of all trades but master of none'). And then I come to a familiar one-- 臥薪嘗胆-- which in Japanese turns into 'gashin shoutan.' Yeah, well, OK. Once I too would have read woxin changdan as 'gashin shoutan' and thought nothing of it. But the explanation that follows---
"In ancient China the Go and the Etsu were at war. After fifteen years of conflict, Kousen, the Etsu king, led his troops to victory over the Go, whose leader Kouryo was slain in battle. Kouryo's son, Fusa, was determined to revenge his father. Every night he slept on a pile of firewood, to inflame his desire for revenge. It obviously did the trick as within three years he won the Battle of Kaikei, where he defeated the Etsu king Kousen. Kousen pleaded for mercy and was allowed to return home after a period of imprisonment. His shame at having surrendered to his fallen foe's son weighed heavily upon him and he resolved to restore his pride the only way he knew how-- by beating Fusa in battle. To give himself courage to carry out this endeavour, he covered the floor of his bedroom with the livers of wild animals (in Japanese the character for liver also means courage.) He licked up all the liver to give him courage, and thus fortified, set out with his faithful retainer Hanrei to wreak terrible revenge on Fusa. It took them twenty-two years, but eventually they did it.
From which I conclude that either there's a totally different story current in Japan about Gou Jian and Fu Chai, or the Japanese author of the book supplied the story as she remembered it from a chance encounter somewhere in middle school, the way the authors of the bad quartos (supposedly) reproduced Shakespeare's plays from memory after a lapse of many years.
Quite apart from liver-strewn chambers and Fu Chai sleeping on brushwood, it just strikes me as *weird* now to call a kingdom Etsu, and rather worse to call the king of Go a word that means 'tuft' or 'tassel.'