According to the Jesuits, Chinese history is free from this defect. Father Moyria de Maillac (commonly called Mailla), in the long introductions to his _Histoire générale de la Chine_, begs us to put our full trust in the Chinese historians, and pleads that, however mendacious the lower orders of the nation, the better classes love the truth, and the historians are honest and accurate. But such pleas in bar of investigation and verification are of little weight unless it can be shown that Chinese historians never drew (in good faith) erroneous conclusions, never mistook the meaning of a document, were never misinformed, and never made a slip in writing. As Gibbon clearly saw,[285] the Jesuits were blinded by admiration of the Celestials; their sharp, critical sagacity was blunted by the air of sincerity displayed in Chinese books.[286] But this “accent de sincérité” is ruthlessly treated by MM. Langlois and Seignobos: “C’est une impression presque irrésistible, mais elle n’en est pas moins une illusion. Il n’y a aucun critérium extérieur ni de la sincérité ni de l’exactitude. ‘L’accent de sincérité,’ c’est l’apparence de la conviction; un orateur, un acteur, un menteur d’habitude l’auront plus facilement en mentant qu’un homme indécis en disant ce qu’il croit. La vigeur de l’affirmation ne prouve pas toujours la vigeur de la conviction, mais seulement l’habileté ou l’effronterie. De même l’abondance et la précision des détails, bien quelles fassent une vive impression sur les lecteurs inexpérimentés, ne garantissent pas l’exactitude des faits;[287] elles ne renseignent que sur l’imagination de l’auteur quand il est sincère ou sur son impudence quand il ne l’est pas. On est porté de dire d’un récit circonstancié: ‘Des choses de ce genre ne s’inventent pas.’ Elles ne s’inventent pas, mais elles se transportent très facilement d’un personage, d’un pays ou d’un temps à un autre.—Aucun caractère extérieur d’un document ne dispense donc d’en faire la critique.”[288] In spite of their zeal for the truth, Chinese historians are no more infallible than others, and it is certain that they were unconsciously led into error at times by the change in meaning which military words underwent in China as well as elsewhere. Thus Mao-yiian-i erroneously believed that _huo-p’áu_ meant _cannon_ in old times, as it did in his own. But from a sketch he has fortunately given of one (reproduced by Romocki, i. 41) it is clear that it originally meant a machine for scattering blazing incendiary matter. The first two questions that present themselves are: (1) Did the Chinese make use of gunpowder in a very distant past? and (2) did they possess an explosive shell in 1232?