Art of War 13.22
The Art of War (孫子兵法), The Use Of Spies 用間篇
因是而知之故鄕間內間可得而使也
It is through the information brought by the converted spy that we are able to acquire and employ local and inward spies.
Lionel Giles (1910), Sun Tzŭ on the Art of War (1910), with Giles' notes — public domain.
Lionel Giles's notes
Tu Yu expands 因是而知之 into 因反敵間而知敵情 “through conversion of the enemy’s spies we learn the enemy’s
condition.” And Chang Yü says: 因是反間知彼鄕人之貪利者官人之人有隙者誘而使之 “We must tempt the converted spy into our service, because it is he that knows which of the local inhabitants are greedy of gain, and which of the officials are open to corruption.” In the T‘ung Tien, 鄕 has been altered to 因, doubtless
for the sake of uniformity with §9.
Character glossary
- 因yīncause, reason; by; because
- 是shìto be; indeed, right, yes; okay
- 而érand, and then, and yet; but
- 知zhīto know, to perceive, to comprehend
- 之zhīmarks preceding phrase as modifier of fo
- 故gùreason, cause; happening, instance
- 鄕xiāngcountry; rural; village
- 間jiānbetween, among; midpoint; space, place,
- 內nèiinside
- 可kěmay, can, -able; possibly
- 得déto obtain, to get, to acquire; suitable,
- 使shǐcause, mission, orders; envoy, messenger
- 也yěalso, too
Passages with shared wording
- Art of War 13.21
- Zhuangzi The Identity of Contraries
- Art of War 13.7
- Art of War 13.10
- Analects 14.44
- Analects 17.4
Data: English Wikisource (Public domain texts; transcription CC BY-SA 4.0). Retrieved 2026-10-22.