On the Upper Limit and Lower Limit of Zuo Zhuan's Writing

Having a comprehensive survey on scholars' research and proof in the previous dynasties,we can see the Warring States,at least recorded the history events,the events of astronomy,quotations of all kinds of books,language appropriate to the occasion,and prediction.Zuo did not oppear before the 5th Year of Wei Sijun(320 B.C.).What Shi Chun transcribed purely from Zuo Zhuan was the Wei Xiangwang's funeral object.Therefore,Zuo Zhuan was written in the year of Wei Xiangwang's death(296 B.C.).Generally speaking,Zuo Zhuan was written between 320 B.C.to 296 B.C..Zuo Zhuan's author was a person from the Lu State and had close(relations) with the Wei State.