These two paragraphs are extremely valuable as evidence of the date of composition. They assign the work to the period of the struggle between Wu and Yüeh . So much has been observed by Pi I-hsün . But what has hitherto escaped notice is that they also seriously impair the credibility of Ssǔ-ma Chʽien’s narrative. As we have seen above, the first positive date given in connection with Sun Wu is 512 BC . He is then spoken of as a general, acting as confidential adviser to Ho Lu , so that his alleged introduction to that monarch had already taken place, and of course the 13 chapters must have been written earlier still. But at that time, and for several years after, down to the capture of Ying