[Word for word, the translation here is: "If spy matters are heard before [our plans] are carried out," etc. Sun Tzŭ’s main point in this passage is: Whereas you kill the spy himself "as a punishment for letting out the secret," the object of killing the other man is only, as Ch’en Hao puts it, "to stop his mouth" and prevent 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."]
- 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, the aides-de- camp,
[Literally "visitors", is equivalent, as Tu Yu says, to "those whose duty it is to keep the general supplied with information," which naturally necessitates frequent interviews with him.]
the door-keepers and sentries of the general in command. 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.]
- The enemy’s spies who have come to spy on us must be sought out, tempted with bribes, led away and comfortably housed. Thus they will become converted spies and available for our service.