There is every reason to suppose, then, that the 13 chapters existed in the time of Ssŭ-ma Ch‘ien practically as we have them now. That the work was then well known he tells us in so many words: “Sun Tzŭ’s 13 Chapters and Wu Ch‘i’s Art of War are the two books that people commonly refer to on the subject of military matters. Both of them are widely distributed, so I will not discuss them here.”[48] But as we go further back, serious difficulties begin to arise. The salient fact which has to be faced is that the _Tso Chuan_, the great contemporary record, makes no mention whatever of Sun Wu, either as a general or as a writer. It is natural, in view of this awkward circumstance, that many scholars should not only cast doubt on the story of Sun Wu as given in the _Shih Chi_, but even show themselves frankly sceptical as to the existence of the man at all. The most powerful presentment of this side of the case is to be found in the following disquisition by 葉水心 Yeh Shui-hsin:[49]— It is stated in Ssŭ-ma Ch‘ien’s history that Sun Wu was a native of the Ch‘i State, and employed by Wu; and that in the reign of Ho Lü he crushed Ch‘u, entered Ying, and was a great general. But in Tso’s Commentary no Sun Wu appears at all. It is true that Tso’s Commentary need not contain absolutely everything that other histories contain. But Tso has not omitted to mention vulgar plebeians and hireling ruffians such as Ying K‘ao-shu,[50] Ts‘ao Kuei,[51] Chu Chih-wu[52] and Chuan Shê-chu.[53] In the case of Sun Wu, whose fame and achievements were so brilliant, the omission is much more glaring. Again, details are given, in their due order, about his contemporaries Wu Yüan and the Minister P‘ei.[54] Is it credible that Sun Wu alone should have been passed over?[55] In point of literary style, Sun Tzŭ’s work belongs to the same school as _Kuan Tzŭ_,[56] the _Liu T‘ao_,[57] and the _Yüeh Yü_,[58] and may have been the production of some private scholar living towards the end of the “Spring and Autumn” or the beginning of the “Warring States” period.[59] The story that his precepts were actually applied by the Wu State, is merely the outcome of big talk on the part of his followers.[60] From the flourishing period of the Chou dynasty[61] down to the time of the “Spring and Autumn,” all military commanders were statesmen as well, and the class of professional generals, for conducting external campaigns, did not then exist. It was not until the period of the “Six States”[62] that this custom changed. Now although Wu was an uncivilised State, is it conceivable that Tso should have left unrecorded the fact that Sun Wu was a great general and yet held no civil office? What we are told, therefore, about Jang-chü[63] and Sun Wu, is not authentic matter, but the reckless fabrication of theorising pundits. The story of Ho Lü’s experiment on the women, in particular, is utterly preposterous and incredible.[64]