Living in the uneasy time of the reigns of Han Chengdi 成帝 and his two successors, and Wang Mang's establishment of his own dynasty, Liu Xin 劉 歆 (46 B.C. to A.D.23) contributed basically to what would become China's intellectual tradition and heritage. Best known for the part that he played in the collection and classification of literature, he wrote with a greater degree of initiative and with a more radical frame of mind than his father Liu Xiang 劉向 (79‒8 B.C.). A supporter of Wang Mang 王莽 (45 B.C.‒ A.D.23) in intellectual terms, he may well have composed the latter's formal pronouncements, but he died by his own hand after involvement in a plot to overthrow him. Author of several fu 賦 , Liu Xin wrote the treatise on Pitch-pipes and calendar (Lü li zhi 律曆志 ) that is now incorporated in the Han shu 漢書 , where he treated astronomy, harmonics, mathematics and history as aspects of a single cosmic system. Recognising the value of some newly found texts, he propounded the virtues of the Zuo zhuan 左傳 and criticised some of his contemporary scholars for their obdurate adherence to their own ideas, irrespective of newly found evidence. His own historical record, the Shi jing 世經 , varies from other accounts, both in the sequences of China's mythological rulers and in matters of dating. He argued for the retention of the honorary title conferred on Han Wudi 武帝 on the grounds that he had merited it, and thereby assured the continuity of that emperor's reputation. Against some, Liu Xin wrote in favor of addressing the cults of state to Heaven rather than to other deities. Calling on the Zuo zhuan to explain the occurrences of abnormalities of nature, he was also ready to identify the moral issues that were involved.