17. 非微妙不能得間之實
Without subtle ingenuity of mind, one cannot make certain of the truth of their reports.
Mei Yao-ch‘ên says: “Be on your guard against the possibility of spies going over to the service of the enemy.” The T‘ung Tien and Yü Lan read 密 for 妙.
18. 微哉微哉無所不用間也
Be subtle! be subtle!
Cf. VI. § 9: 微乎微乎. Capt. Calthrop translates: “Wonderful indeed is the power of spies.”
and use your spies for every kind of business.
19. 間事未發而先聞者間與所告者皆死
If a secret piece of news is divulged by a spy before the time is ripe, he must be put to death together with the man to whom the secret was told.
The Chinese here is so concise and elliptical that some expansion is necessary for the proper understanding of it. 間事 denotes important information about the enemy obtained from a surviving spy. The subject of 未發, however, is not this information itself, but the secret stratagem built up on the strength of it. 聞者 means “is heard”—by anybody else. Thus, word for word, we get: “If spy matters are heard before [our plans] are carried out,” etc. Capt. Calthrop, in translating 間與所告者 “the spy who told the matter, and the man who repeated the same,” may appeal to the authority of the commentators; but he surely misses the main point of Sun Tzŭ’s injunction. For, whereas you kill the spy himself 惡其泄 “as a punishment for letting out the secret,” the object of killing the other man is only, as Ch‘ên Hao puts it, 以滅口 “to stop his mouth” and prevent the news leaking any further. If it had already been repeated to others, this object would not be gained. Either way, Sun Tzŭ lays himself open to the charge of inhumanity, though Tu Mu tries to defend him by saying that the man deserves to be put to death, for the spy would certainly not have told the secret unless the other had been at pains to worm it out of him. The T‘ung Tien and Yü Lan have the reading ... 先聞其間者與, etc., which, while not affecting the sense, strikes me as being better than that of the standard text. The T‘u Shu has ... 聞與所告者, which I suppose would mean: “the man who heard the secret and the man who told it to him.”
20. 凡軍之所欲擊城之所欲攻人之所欲殺必先知其守將左右謁者門者舍人之姓名令吾間 必索知之
Whether the object be to crush an army, to storm a city, or to assassinate an individual, it is always necessary to begin by finding out the names of the attendants,
左右 is a comprehensive term for those who wait on others, servants and retainers generally. Capt. Calthrop is hardly happy in rendering it “right-hand men.”
the aides-de-camp,
謁者, literally “visitors,” is equivalent, as Tu Yu says, to 主告事者 “those whose duty it is to keep the general supplied with information,” which naturally necessitates frequent interviews with him. Chang Yü goes too far afield for an explanation in saying that they are 典賓客之將 “the leaders of mercenary troops.”
the door-keepers and sentries
閽吏 and 守舍之人.
of the general in command.
守將, according to Chang Yü, is simply 守官任職之將 “a general on active service.” Capt. Calthrop is wrong, I think, in making 守將 directly dependent on 姓名 (... “the names of the general in charge,” etc.).
Our spies must be commissioned to ascertain these.
As the first step, no doubt, towards finding out if any of these important functionaries can be won over by bribery. Capt. Calthrop blunders badly with: “Then set the spies to watch them.”
21. 必索敵人之間來間我者因而利之導而舍之故反間可得而用也
The enemy’s spies who have come to spy on us must be sought out,
必索 is omitted by the T‘ung Tien and Yü Lan. Its recurrence is certainly suspicious, though the sense may seem to gain by it. The T‘u Shu has this variation: ... 敵間之來間吾者, etc.
tempted with bribes, led away and comfortably housed.
舍 is probably more than merely 居止 or 稽留 “detain.” Cf. § 25 ad fin., where Sun Tzŭ insists that these converted spies shall be treated well. Chang Yü’s paraphrase is 館舍.
Thus they will become converted spies and available for our service.
22. 因是而知之故鄉間內間可得而使也
Sun Tzŭ on the Art of War: the Oldest Military Treatise in the World · The Wunder Library — complete classics, free to read, with narration.