Yao-ch’en, and on the whole not a very trustworthy guide. He is fond of comparing his own commentary with that of Ts’ao Kung, but the comparison is not often flattering to him. We learn from Ch’ao Kung-wu that Wang Hsi revised the ancient text of Sun Tzŭ, filling up lacunae and correcting mistakes. [45]
- HO YEN-HSI of the Sung dynasty. The personal name of this commentator is given as above by Cheng Ch’iao in the Tung Chih, written about the middle of the twelfth century, but he appears simply as Ho Shih in the Yu Hai, and Ma Tuan-lin quotes Ch’ao Kung-wu as saying that his personal name is unknown. There seems to be no reason to doubt Cheng Ch’iao’s statement, otherwise I should have been inclined to hazard a guess and identify him with one Ho Ch’u-fei, the author of a short treatise on war, who lived in the latter part of the 11th century. Ho Shih’s commentary, in the words of the T’ien-i-ko catalogue, "contains helpful additions" here and there, but is chiefly remarkable for the copious extracts taken, in adapted form, from the dynastic histories and other sources.
- CHANG YU. The list closes with a commentator of no great originality perhaps, but gifted with admirable powers of lucid exposition. His commentator is based on that of Ts’ao Kung, whose terse sentences he contrives to expand and develop in masterly fashion. Without Chang Yu, it is safe to say that much of Ts’ao Kung’s commentary would have remained cloaked in its pristine obscurity and therefore valueless. His work is not mentioned in the Sung history, the T’ung K’ao, or the Yu Hai, but it finds a niche in the T’ung Chih, which also names him as the author of the "Lives of Famous Generals." [46]
It is rather remarkable that the last-named four should all have flourished within so short a space of time. Ch’ao Kung-wu accounts for it by saying: