夫史之为用,亦大矣哉!上通千百年之事,下垂千百世之例。借事喻物,以明治国之大道;按制依度,以应乡里之琐事。至其使命,则为“究天人之际,穷古今之变。”史之为用,史之使命,既如此重大,故凡治史者,非据切实之学问,明慧之识见,干练之才器,不足以语此也。《旧唐书》刘知几本传曰:“史 History of the husband to use, but also a big guzai! On the pass thousands of years, sagging thousands of world example. By conspiratorial things, to the rule of the country’s avenue; according to the system according to the degree, should be the trivial things in the village. To its mission, it is ”the history of the mission, the mission of history, both so significant, so who rule the history, non-practical knowledge, knowledge of Minghui, Clerical talent, not enough to say this too. “Old Tang book,” Liu know a few pass said: "History